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Make single .dtb targets also with DTC_FLAGS #8
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Make single .dtb targets also with DTC_FLAGS #8
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Patches need to be again https://github.com/beagleboard/kernel/tree/3.8 |
In which section should I put it? |
build/ or arm/ |
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Platforms export their SMP callbacks by populating arc_smp_ops. The population itself needs to be done pretty early, from init_early callback. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Arnd Bergmann <arnd@arndb.de>
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…ernel/git/vgupta/arc Pull new ARC architecture from Vineet Gupta: "Initial ARC Linux port with some fixes on top for 3.9-rc1: I would like to introduce the Linux port to ARC Processors (from Synopsys) for 3.9-rc1. The patch-set has been discussed on the public lists since Nov and has received a fair bit of review, specially from Arnd, tglx, Al and other subsystem maintainers for DeviceTree, kgdb... The arch bits are in arch/arc, some asm-generic changes (acked by Arnd), a minor change to PARISC (acked by Helge). The series is a touch bigger for a new port for 2 main reasons: 1. It enables a basic kernel in first sub-series and adds ptrace/kgdb/.. later 2. Some of the fallout of review (DeviceTree support, multi-platform- image support) were added on top of orig series, primarily to record the revision history. This updated pull request additionally contains - fixes due to our GNU tools catching up with the new syscall/ptrace ABI - some (minor) cross-arch Kconfig updates." * tag 'arc-v3.9-rc1-late' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc: (82 commits) ARC: split elf.h into uapi and export it for userspace ARC: Fixup the current ABI version ARC: gdbserver using regset interface possibly broken ARC: Kconfig cleanup tracking cross-arch Kconfig pruning in merge window ARC: make a copy of flat DT ARC: [plat-arcfpga] DT arc-uart bindings change: "baud" => "current-speed" ARC: Ensure CONFIG_VIRT_TO_BUS is not enabled ARC: Fix pt_orig_r8 access ARC: [3.9] Fallout of hlist iterator update ARC: 64bit RTSC timestamp hardware issue ARC: Don't fiddle with non-existent caches ARC: Add self to MAINTAINERS ARC: Provide a default serial.h for uart drivers needing BASE_BAUD ARC: [plat-arcfpga] defconfig for fully loaded ARC Linux ARC: [Review] Multi-platform image #8: platform registers SMP callbacks ARC: [Review] Multi-platform image #7: SMP common code to use callbacks ARC: [Review] Multi-platform image #6: cpu-to-dma-addr optional ARC: [Review] Multi-platform image #5: NR_IRQS defined by ARC core ARC: [Review] Multi-platform image #4: Isolate platform headers ARC: [Review] Multi-platform image #3: switch to board callback ...
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The following script will produce a kernel oops: sudo ip netns add v sudo ip netns exec v ip ad add 127.0.0.1/8 dev lo sudo ip netns exec v ip link set lo up sudo ip netns exec v ip ro add 224.0.0.0/4 dev lo sudo ip netns exec v ip li add vxlan0 type vxlan id 42 group 239.1.1.1 dev lo sudo ip netns exec v ip link set vxlan0 up sudo ip netns del v where inspect by gdb: Program received signal SIGSEGV, Segmentation fault. [Switching to Thread 107] 0xffffffffa0289e33 in ?? () (gdb) bt #0 vxlan_leave_group (dev=0xffff88001bafa000) at drivers/net/vxlan.c:533 #1 vxlan_stop (dev=0xffff88001bafa000) at drivers/net/vxlan.c:1087 #2 0xffffffff812cc498 in __dev_close_many (head=head@entry=0xffff88001f2e7dc8) at net/core/dev.c:1299 #3 0xffffffff812cd920 in dev_close_many (head=head@entry=0xffff88001f2e7dc8) at net/core/dev.c:1335 #4 0xffffffff812cef31 in rollback_registered_many (head=head@entry=0xffff88001f2e7dc8) at net/core/dev.c:4851 #5 0xffffffff812cf040 in unregister_netdevice_many (head=head@entry=0xffff88001f2e7dc8) at net/core/dev.c:5752 #6 0xffffffff812cf1ba in default_device_exit_batch (net_list=0xffff88001f2e7e18) at net/core/dev.c:6170 #7 0xffffffff812cab27 in cleanup_net (work=<optimized out>) at net/core/net_namespace.c:302 #8 0xffffffff810540ef in process_one_work (worker=0xffff88001ba9ed40, work=0xffffffff8167d020) at kernel/workqueue.c:2157 #9 0xffffffff810549d0 in worker_thread (__worker=__worker@entry=0xffff88001ba9ed40) at kernel/workqueue.c:2276 torvalds#10 0xffffffff8105870c in kthread (_create=0xffff88001f2e5d68) at kernel/kthread.c:168 torvalds#11 <signal handler called> torvalds#12 0x0000000000000000 in ?? () torvalds#13 0x0000000000000000 in ?? () (gdb) fr 0 #0 vxlan_leave_group (dev=0xffff88001bafa000) at drivers/net/vxlan.c:533 533 struct sock *sk = vn->sock->sk; (gdb) l 528 static int vxlan_leave_group(struct net_device *dev) 529 { 530 struct vxlan_dev *vxlan = netdev_priv(dev); 531 struct vxlan_net *vn = net_generic(dev_net(dev), vxlan_net_id); 532 int err = 0; 533 struct sock *sk = vn->sock->sk; 534 struct ip_mreqn mreq = { 535 .imr_multiaddr.s_addr = vxlan->gaddr, 536 .imr_ifindex = vxlan->link, 537 }; (gdb) p vn->sock $4 = (struct socket *) 0x0 The kernel calls `vxlan_exit_net` when deleting the netns before shutting down vxlan interfaces. Later the removal of all vxlan interfaces, where `vn->sock` is already gone causes the oops. so we should manually shutdown all interfaces before deleting `vn->sock` as the patch does. Signed-off-by: Zang MingJie <zealot0630@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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We can deadlock (s_active and fcoe_config_mutex) if a port is being destroyed at the same time one is being created. [ 4200.503113] ====================================================== [ 4200.503114] [ INFO: possible circular locking dependency detected ] [ 4200.503116] 3.8.0-rc5+ #8 Not tainted [ 4200.503117] ------------------------------------------------------- [ 4200.503118] kworker/3:2/2492 is trying to acquire lock: [ 4200.503119] (s_active#292){++++.+}, at: [<ffffffff8122d20b>] sysfs_addrm_finish+0x3b/0x70 [ 4200.503127] but task is already holding lock: [ 4200.503128] (fcoe_config_mutex){+.+.+.}, at: [<ffffffffa02f3338>] fcoe_destroy_work+0xe8/0x120 [fcoe] [ 4200.503133] which lock already depends on the new lock. [ 4200.503135] the existing dependency chain (in reverse order) is: [ 4200.503136] -> #1 (fcoe_config_mutex){+.+.+.}: [ 4200.503139] [<ffffffff810c7711>] lock_acquire+0xa1/0x140 [ 4200.503143] [<ffffffff816ca7be>] mutex_lock_nested+0x6e/0x360 [ 4200.503146] [<ffffffffa02f11bd>] fcoe_enable+0x1d/0xb0 [fcoe] [ 4200.503148] [<ffffffffa02f127d>] fcoe_ctlr_enabled+0x2d/0x50 [fcoe] [ 4200.503151] [<ffffffffa02ffbe8>] store_ctlr_enabled+0x38/0x90 [libfcoe] [ 4200.503154] [<ffffffff81424878>] dev_attr_store+0x18/0x30 [ 4200.503157] [<ffffffff8122b750>] sysfs_write_file+0xe0/0x150 [ 4200.503160] [<ffffffff811b334c>] vfs_write+0xac/0x180 [ 4200.503162] [<ffffffff811b3692>] sys_write+0x52/0xa0 [ 4200.503164] [<ffffffff816d7159>] system_call_fastpath+0x16/0x1b [ 4200.503167] -> #0 (s_active#292){++++.+}: [ 4200.503170] [<ffffffff810c680f>] __lock_acquire+0x135f/0x1c90 [ 4200.503172] [<ffffffff810c7711>] lock_acquire+0xa1/0x140 [ 4200.503174] [<ffffffff8122c626>] sysfs_deactivate+0x116/0x160 [ 4200.503176] [<ffffffff8122d20b>] sysfs_addrm_finish+0x3b/0x70 [ 4200.503178] [<ffffffff8122b2eb>] sysfs_hash_and_remove+0x5b/0xb0 [ 4200.503180] [<ffffffff8122f3d1>] sysfs_remove_group+0x61/0x100 [ 4200.503183] [<ffffffff814251eb>] device_remove_groups+0x3b/0x60 [ 4200.503185] [<ffffffff81425534>] device_remove_attrs+0x44/0x80 [ 4200.503187] [<ffffffff81425e97>] device_del+0x127/0x1c0 [ 4200.503189] [<ffffffff81425f52>] device_unregister+0x22/0x60 [ 4200.503191] [<ffffffffa0300970>] fcoe_ctlr_device_delete+0xe0/0xf0 [libfcoe] [ 4200.503194] [<ffffffffa02f1b5c>] fcoe_interface_cleanup+0x6c/0xa0 [fcoe] [ 4200.503196] [<ffffffffa02f3355>] fcoe_destroy_work+0x105/0x120 [fcoe] [ 4200.503198] [<ffffffff8107ee91>] process_one_work+0x1a1/0x580 [ 4200.503203] [<ffffffff81080c6e>] worker_thread+0x15e/0x440 [ 4200.503205] [<ffffffff8108715a>] kthread+0xea/0xf0 [ 4200.503207] [<ffffffff816d70ac>] ret_from_fork+0x7c/0xb0 [ 4200.503209] other info that might help us debug this: [ 4200.503211] Possible unsafe locking scenario: [ 4200.503212] CPU0 CPU1 [ 4200.503213] ---- ---- [ 4200.503214] lock(fcoe_config_mutex); [ 4200.503215] lock(s_active#292); [ 4200.503218] lock(fcoe_config_mutex); [ 4200.503219] lock(s_active#292); [ 4200.503221] *** DEADLOCK *** [ 4200.503223] 3 locks held by kworker/3:2/2492: [ 4200.503224] #0: (fcoe){.+.+.+}, at: [<ffffffff8107ee2b>] process_one_work+0x13b/0x580 [ 4200.503228] #1: ((&port->destroy_work)){+.+.+.}, at: [<ffffffff8107ee2b>] process_one_work+0x13b/0x580 [ 4200.503232] #2: (fcoe_config_mutex){+.+.+.}, at: [<ffffffffa02f3338>] fcoe_destroy_work+0xe8/0x120 [fcoe] [ 4200.503236] stack backtrace: [ 4200.503238] Pid: 2492, comm: kworker/3:2 Not tainted 3.8.0-rc5+ #8 [ 4200.503240] Call Trace: [ 4200.503243] [<ffffffff816c2f09>] print_circular_bug+0x1fb/0x20c [ 4200.503246] [<ffffffff810c680f>] __lock_acquire+0x135f/0x1c90 [ 4200.503248] [<ffffffff810c463a>] ? debug_check_no_locks_freed+0x9a/0x180 [ 4200.503250] [<ffffffff810c7711>] lock_acquire+0xa1/0x140 [ 4200.503253] [<ffffffff8122d20b>] ? sysfs_addrm_finish+0x3b/0x70 [ 4200.503255] [<ffffffff8122c626>] sysfs_deactivate+0x116/0x160 [ 4200.503258] [<ffffffff8122d20b>] ? sysfs_addrm_finish+0x3b/0x70 [ 4200.503260] [<ffffffff8122d20b>] sysfs_addrm_finish+0x3b/0x70 [ 4200.503262] [<ffffffff8122b2eb>] sysfs_hash_and_remove+0x5b/0xb0 [ 4200.503265] [<ffffffff8122f3d1>] sysfs_remove_group+0x61/0x100 [ 4200.503273] [<ffffffff814251eb>] device_remove_groups+0x3b/0x60 [ 4200.503275] [<ffffffff81425534>] device_remove_attrs+0x44/0x80 [ 4200.503277] [<ffffffff81425e97>] device_del+0x127/0x1c0 [ 4200.503279] [<ffffffff81425f52>] device_unregister+0x22/0x60 [ 4200.503282] [<ffffffffa0300970>] fcoe_ctlr_device_delete+0xe0/0xf0 [libfcoe] [ 4200.503285] [<ffffffffa02f1b5c>] fcoe_interface_cleanup+0x6c/0xa0 [fcoe] [ 4200.503287] [<ffffffffa02f3355>] fcoe_destroy_work+0x105/0x120 [fcoe] [ 4200.503290] [<ffffffff8107ee91>] process_one_work+0x1a1/0x580 [ 4200.503292] [<ffffffff8107ee2b>] ? process_one_work+0x13b/0x580 [ 4200.503295] [<ffffffffa02f3250>] ? fcoe_if_destroy+0x230/0x230 [fcoe] [ 4200.503297] [<ffffffff81080c6e>] worker_thread+0x15e/0x440 [ 4200.503299] [<ffffffff81080b10>] ? busy_worker_rebind_fn+0x100/0x100 [ 4200.503301] [<ffffffff8108715a>] kthread+0xea/0xf0 [ 4200.503304] [<ffffffff81087070>] ? kthread_create_on_node+0x160/0x160 [ 4200.503306] [<ffffffff816d70ac>] ret_from_fork+0x7c/0xb0 [ 4200.503308] [<ffffffff81087070>] ? kthread_create_on_node+0x160/0x160 Signed-off-by: Robert Love <robert.w.love@intel.com> Tested-by: Jack Morgan <jack.morgan@intel.com>
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Dropping the session's reference count after the client's means we leave a window where the session's se_client pointer is NULL. An xpt_user callback that encounters such a session may then crash: [ 303.956011] BUG: unable to handle kernel NULL pointer dereference at 0000000000000318 [ 303.959061] IP: [<ffffffff81481a8e>] _raw_spin_lock+0x1e/0x40 [ 303.959061] PGD 37811067 PUD 3d498067 PMD 0 [ 303.959061] Oops: 0002 [#8] PREEMPT SMP [ 303.959061] Modules linked in: md5 nfsd auth_rpcgss nfs_acl snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_page_alloc microcode psmouse snd_timer serio_raw pcspkr evdev snd soundcore i2c_piix4 i2c_core intel_agp intel_gtt processor button nfs lockd sunrpc fscache ata_generic pata_acpi ata_piix uhci_hcd libata btrfs usbcore usb_common crc32c scsi_mod libcrc32c zlib_deflate floppy virtio_balloon virtio_net virtio_pci virtio_blk virtio_ring virtio [ 303.959061] CPU 0 [ 303.959061] Pid: 264, comm: nfsd Tainted: G D 3.8.0-ARCH+ torvalds#156 Bochs Bochs [ 303.959061] RIP: 0010:[<ffffffff81481a8e>] [<ffffffff81481a8e>] _raw_spin_lock+0x1e/0x40 [ 303.959061] RSP: 0018:ffff880037877dd8 EFLAGS: 00010202 [ 303.959061] RAX: 0000000000000100 RBX: ffff880037a2b698 RCX: ffff88003d879278 [ 303.959061] RDX: ffff88003d879278 RSI: dead000000100100 RDI: 0000000000000318 [ 303.959061] RBP: ffff880037877dd8 R08: ffff88003c5a0f00 R09: 0000000000000002 [ 303.959061] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 [ 303.959061] R13: 0000000000000318 R14: ffff880037a2b680 R15: ffff88003c1cbe00 [ 303.959061] FS: 0000000000000000(0000) GS:ffff88003fc00000(0000) knlGS:0000000000000000 [ 303.959061] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 303.959061] CR2: 0000000000000318 CR3: 000000003d49c000 CR4: 00000000000006f0 [ 303.959061] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 303.959061] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [ 303.959061] Process nfsd (pid: 264, threadinfo ffff880037876000, task ffff88003c1fd0a0) [ 303.959061] Stack: [ 303.959061] ffff880037877e08 ffffffffa03772ec ffff88003d879000 ffff88003d879278 [ 303.959061] ffff88003d879080 0000000000000000 ffff880037877e38 ffffffffa0222a1f [ 303.959061] 0000000000107ac0 ffff88003c22e000 ffff88003d879000 ffff88003c1cbe00 [ 303.959061] Call Trace: [ 303.959061] [<ffffffffa03772ec>] nfsd4_conn_lost+0x3c/0xa0 [nfsd] [ 303.959061] [<ffffffffa0222a1f>] svc_delete_xprt+0x10f/0x180 [sunrpc] [ 303.959061] [<ffffffffa0223d96>] svc_recv+0xe6/0x580 [sunrpc] [ 303.959061] [<ffffffffa03587c5>] nfsd+0xb5/0x140 [nfsd] [ 303.959061] [<ffffffffa0358710>] ? nfsd_destroy+0x90/0x90 [nfsd] [ 303.959061] [<ffffffff8107ae00>] kthread+0xc0/0xd0 [ 303.959061] [<ffffffff81010000>] ? perf_trace_xen_mmu_set_pte_at+0x50/0x100 [ 303.959061] [<ffffffff8107ad40>] ? kthread_freezable_should_stop+0x70/0x70 [ 303.959061] [<ffffffff814898ec>] ret_from_fork+0x7c/0xb0 [ 303.959061] [<ffffffff8107ad40>] ? kthread_freezable_should_stop+0x70/0x70 [ 303.959061] Code: ff ff 5d c3 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 55 65 48 8b 04 25 f0 c6 00 00 48 89 e5 83 80 44 e0 ff ff 01 b8 00 01 00 00 <3e> 66 0f c1 07 0f b6 d4 38 c2 74 0f 66 0f 1f 44 00 00 f3 90 0f [ 303.959061] RIP [<ffffffff81481a8e>] _raw_spin_lock+0x1e/0x40 [ 303.959061] RSP <ffff880037877dd8> [ 303.959061] CR2: 0000000000000318 [ 304.001218] ---[ end trace 2d809cd4a7931f5a ]--- [ 304.001903] note: nfsd[264] exited with preempt_count 2 Reported-by: Bryan Schumaker <bjschuma@netapp.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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i2c: suppress lockdep warning on delete_device Since commit 846f997 the following lockdep warning is thrown in case i2c device is removed (via delete_device sysfs attribute) which contains subdevices (e.g. i2c multiplexer): ============================================= [ INFO: possible recursive locking detected ] 3.8.7-0-sampleversion-fct #8 Tainted: G O --------------------------------------------- bash/3743 is trying to acquire lock: (s_active#110){++++.+}, at: [<ffffffff802b3048>] sysfs_hash_and_remove+0x58/0xc8 but task is already holding lock: (s_active#110){++++.+}, at: [<ffffffff802b3cb8>] sysfs_write_file+0xc8/0x208 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(s_active#110); lock(s_active#110); *** DEADLOCK *** May be due to missing lock nesting notation 4 locks held by bash/3743: #0: (&buffer->mutex){+.+.+.}, at: [<ffffffff802b3c3c>] sysfs_write_file+0x4c/0x208 #1: (s_active#110){++++.+}, at: [<ffffffff802b3cb8>] sysfs_write_file+0xc8/0x208 #2: (&adap->userspace_clients_lock/1){+.+.+.}, at: [<ffffffff80454a18>] i2c_sysfs_delete_device+0x90/0x238 #3: (&__lockdep_no_validate__){......}, at: [<ffffffff803dcc24>] device_release_driver+0x24/0x48 stack backtrace: Call Trace: [<ffffffff80575cc8>] dump_stack+0x8/0x34 [<ffffffff801b50fc>] __lock_acquire+0x161c/0x2110 [<ffffffff801b5c3c>] lock_acquire+0x4c/0x70 [<ffffffff802b60cc>] sysfs_addrm_finish+0x19c/0x1e0 [<ffffffff802b3048>] sysfs_hash_and_remove+0x58/0xc8 [<ffffffff802b7d8c>] sysfs_remove_group+0x64/0x148 [<ffffffff803d990c>] device_remove_attrs+0x9c/0x1a8 [<ffffffff803d9b1c>] device_del+0x104/0x1d8 [<ffffffff803d9c18>] device_unregister+0x28/0x70 [<ffffffff8045505c>] i2c_del_adapter+0x1cc/0x328 [<ffffffff8045802c>] i2c_del_mux_adapter+0x14/0x38 [<ffffffffc025c108>] pca954x_remove+0x90/0xe0 [pca954x] [<ffffffff804542f8>] i2c_device_remove+0x80/0xe8 [<ffffffff803dca9c>] __device_release_driver+0x74/0xf8 [<ffffffff803dcc2c>] device_release_driver+0x2c/0x48 [<ffffffff803dbc14>] bus_remove_device+0x13c/0x1d8 [<ffffffff803d9b24>] device_del+0x10c/0x1d8 [<ffffffff803d9c18>] device_unregister+0x28/0x70 [<ffffffff80454b08>] i2c_sysfs_delete_device+0x180/0x238 [<ffffffff802b3cd4>] sysfs_write_file+0xe4/0x208 [<ffffffff8023ddc4>] vfs_write+0xbc/0x160 [<ffffffff8023df6c>] SyS_write+0x54/0xd8 [<ffffffff8013d424>] handle_sys64+0x44/0x64 The problem is already known for USB and PCI subsystems. The reason is that delete_device attribute is defined statically in i2c-core.c and used for all devices in i2c subsystem. Discussion of original USB problem: http://lkml.indiana.edu/hypermail/linux/kernel/1204.3/01160.html Commit 356c05d introduced new macro to suppress lockdep warnings for this special case and included workaround for USB code. LKML discussion of the workaround: http://lkml.indiana.edu/hypermail/linux/kernel/1205.1/03634.html As i2c case is in principle the same, the same workaround could be used here. Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nsn.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Tejun Heo <tj@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Daniel Petre reported crashes in icmp_dst_unreach() with following call graph: #3 [ffff88003fc03938] __stack_chk_fail at ffffffff81037f77 #4 [ffff88003fc03948] icmp_send at ffffffff814d5fec #5 [ffff88003fc03ae8] ipv4_link_failure at ffffffff814a1795 #6 [ffff88003fc03af8] ipgre_tunnel_xmit at ffffffff814e7965 #7 [ffff88003fc03b78] dev_hard_start_xmit at ffffffff8146e032 #8 [ffff88003fc03bc8] sch_direct_xmit at ffffffff81487d66 #9 [ffff88003fc03c08] __qdisc_run at ffffffff81487efd torvalds#10 [ffff88003fc03c48] dev_queue_xmit at ffffffff8146e5a7 torvalds#11 [ffff88003fc03c88] ip_finish_output at ffffffff814ab596 Daniel found a similar problem mentioned in http://lkml.indiana.edu/hypermail/linux/kernel/1007.0/00961.html And indeed this is the root cause : skb->cb[] contains data fooling IP stack. We must clear IPCB in ip_tunnel_xmit() sooner in case dst_link_failure() is called. Or else skb->cb[] might contain garbage from GSO segmentation layer. A similar fix was tested on linux-3.9, but gre code was refactored in linux-3.10. I'll send patches for stable kernels as well. Many thanks to Daniel for providing reports, patches and testing ! Reported-by: Daniel Petre <daniel.petre@rcs-rds.ro> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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…rnel/git/dhowells/linux-fs Pull FS-Cache updates from David Howells: "This contains a number of fixes for various FS-Cache issues plus some cleanups. The commits are, in order: 1) Provide a system wait_on_atomic_t() and wake_up_atomic_t() sharing the bit-wait table (enhancement for #8). 2) Don't put spin_lock() in a while-condition as spin_lock() may have a do {} while(0) wrapper (cleanup). 3) Symbolically name i_mutex lock classes rather than using numbers in CacheFiles (cleanup). 4) Don't sleep in page release if __GFP_FS is not set (deadlock vs ext4). 5) Uninline fscache_object_init() (cleanup for #7). 6) Wrap checks on object state (cleanup for #7). 7) Simplify the object state machine by separating work states from wait states. 8) Simplify cookie retention by objects (NULL pointer deref fix). 9) Remove unused list_to_page() macro (cleanup). 10) Make the remaining-pages counter in the retrieval op atomic (assertion failure fix). 11) Don't use spin_is_locked() in assertions (assertion failure fix)" * tag 'fscache-20130702' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: FS-Cache: Don't use spin_is_locked() in assertions FS-Cache: The retrieval remaining-pages counter needs to be atomic_t cachefiles: remove unused macro list_to_page() FS-Cache: Simplify cookie retention for fscache_objects, fixing oops FS-Cache: Fix object state machine to have separate work and wait states FS-Cache: Wrap checks on object state FS-Cache: Uninline fscache_object_init() FS-Cache: Don't sleep in page release if __GFP_FS is not set CacheFiles: name i_mutex lock class explicitly fs/fscache: remove spin_lock() from the condition in while() Add wait_on_atomic_t() and wake_up_atomic_t()
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Several people reported the warning: "kernel BUG at kernel/timer.c:729!" and the stack trace is: #7 [ffff880214d25c10] mod_timer+501 at ffffffff8106d905 #8 [ffff880214d25c50] br_multicast_del_pg.isra.20+261 at ffffffffa0731d25 [bridge] #9 [ffff880214d25c80] br_multicast_disable_port+88 at ffffffffa0732948 [bridge] torvalds#10 [ffff880214d25cb0] br_stp_disable_port+154 at ffffffffa072bcca [bridge] torvalds#11 [ffff880214d25ce8] br_device_event+520 at ffffffffa072a4e8 [bridge] torvalds#12 [ffff880214d25d18] notifier_call_chain+76 at ffffffff8164aafc torvalds#13 [ffff880214d25d50] raw_notifier_call_chain+22 at ffffffff810858f6 torvalds#14 [ffff880214d25d60] call_netdevice_notifiers+45 at ffffffff81536aad torvalds#15 [ffff880214d25d80] dev_close_many+183 at ffffffff81536d17 torvalds#16 [ffff880214d25dc0] rollback_registered_many+168 at ffffffff81537f68 torvalds#17 [ffff880214d25de8] rollback_registered+49 at ffffffff81538101 torvalds#18 [ffff880214d25e10] unregister_netdevice_queue+72 at ffffffff815390d8 torvalds#19 [ffff880214d25e30] __tun_detach+272 at ffffffffa074c2f0 [tun] torvalds#20 [ffff880214d25e88] tun_chr_close+45 at ffffffffa074c4bd [tun] torvalds#21 [ffff880214d25ea8] __fput+225 at ffffffff8119b1f1 torvalds#22 [ffff880214d25ef0] ____fput+14 at ffffffff8119b3fe torvalds#23 [ffff880214d25f00] task_work_run+159 at ffffffff8107cf7f torvalds#24 [ffff880214d25f30] do_notify_resume+97 at ffffffff810139e1 torvalds#25 [ffff880214d25f50] int_signal+18 at ffffffff8164f292 this is due to I forgot to check if mp->timer is armed in br_multicast_del_pg(). This bug is introduced by commit 9f00b2e (bridge: only expire the mdb entry when query is received). Same for __br_mdb_del(). Tested-by: poma <pomidorabelisima@gmail.com> Reported-by: LiYonghua <809674045@qq.com> Reported-by: Robert Hancock <hancockrwd@gmail.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Stephen Hemminger <stephen@networkplumber.org> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Cong Wang <amwang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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…ifier In fd4363f ("x86: Introduce int3 (breakpoint)-based instruction patching"), the mechanism that was introduced for notifying alternatives code from int3 exception handler that and exception occured was die_notifier. This is however problematic, as early code might be using jump labels even before the notifier registration has been performed, which will then lead to an oops due to unhandled exception. One of such occurences has been encountered by Fengguang: int3: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: CPU: 1 PID: 0 Comm: swapper/1 Not tainted 3.11.0-rc1-01429-g04bf576 #8 task: ffff88000da1b040 ti: ffff88000da1c000 task.ti: ffff88000da1c000 RIP: 0010:[<ffffffff811098cc>] [<ffffffff811098cc>] ttwu_do_wakeup+0x28/0x225 RSP: 0000:ffff88000dd03f10 EFLAGS: 00000006 RAX: 0000000000000000 RBX: ffff88000dd12940 RCX: ffffffff81769c40 RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000001 RBP: ffff88000dd03f28 R08: ffffffff8176a8c0 R09: 0000000000000002 R10: ffffffff810ff484 R11: ffff88000dd129e8 R12: ffff88000dbc90c0 R13: ffff88000dbc90c0 R14: ffff88000da1dfd8 R15: ffff88000da1dfd8 FS: 0000000000000000(0000) GS:ffff88000dd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 00000000ffffffff CR3: 0000000001c88000 CR4: 00000000000006e0 Stack: ffff88000dd12940 ffff88000dbc90c0 ffff88000da1dfd8 ffff88000dd03f48 ffffffff81109e2b ffff88000dd12940 0000000000000000 ffff88000dd03f68 ffffffff81109e9e 0000000000000000 0000000000012940 ffff88000dd03f98 Call Trace: <IRQ> [<ffffffff81109e2b>] ttwu_do_activate.constprop.56+0x6d/0x79 [<ffffffff81109e9e>] sched_ttwu_pending+0x67/0x84 [<ffffffff8110c845>] scheduler_ipi+0x15a/0x2b0 [<ffffffff8104dfb4>] smp_reschedule_interrupt+0x38/0x41 [<ffffffff8173bf5d>] reschedule_interrupt+0x6d/0x80 <EOI> [<ffffffff810ff484>] ? __atomic_notifier_call_chain+0x5/0xc1 [<ffffffff8105cc30>] ? native_safe_halt+0xd/0x16 [<ffffffff81015f10>] default_idle+0x147/0x282 [<ffffffff81017026>] arch_cpu_idle+0x3d/0x5d [<ffffffff81127d6a>] cpu_idle_loop+0x46d/0x5db [<ffffffff81127f5c>] cpu_startup_entry+0x84/0x84 [<ffffffff8104f4f8>] start_secondary+0x3c8/0x3d5 [...] Fix this by directly calling poke_int3_handler() from the int3 exception handler (analogically to what ftrace has been doing already), instead of relying on notifier, registration of which might not have yet been finalized by the time of the first trap. Reported-and-tested-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/alpine.LNX.2.00.1307231007490.14024@pobox.suse.cz Signed-off-by: Ingo Molnar <mingo@kernel.org>
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We used to keep the port's char device structs and the /sys entries around till the last reference to the port was dropped. This is actually unnecessary, and resulted in buggy behaviour: 1. Open port in guest 2. Hot-unplug port 3. Hot-plug a port with the same 'name' property as the unplugged one This resulted in hot-plug being unsuccessful, as a port with the same name already exists (even though it was unplugged). This behaviour resulted in a warning message like this one: -------------------8<--------------------------------------- WARNING: at fs/sysfs/dir.c:512 sysfs_add_one+0xc9/0x130() (Not tainted) Hardware name: KVM sysfs: cannot create duplicate filename '/devices/pci0000:00/0000:00:04.0/virtio0/virtio-ports/vport0p1' Call Trace: [<ffffffff8106b607>] ? warn_slowpath_common+0x87/0xc0 [<ffffffff8106b6f6>] ? warn_slowpath_fmt+0x46/0x50 [<ffffffff811f2319>] ? sysfs_add_one+0xc9/0x130 [<ffffffff811f23e8>] ? create_dir+0x68/0xb0 [<ffffffff811f2469>] ? sysfs_create_dir+0x39/0x50 [<ffffffff81273129>] ? kobject_add_internal+0xb9/0x260 [<ffffffff812733d8>] ? kobject_add_varg+0x38/0x60 [<ffffffff812734b4>] ? kobject_add+0x44/0x70 [<ffffffff81349de4>] ? get_device_parent+0xf4/0x1d0 [<ffffffff8134b389>] ? device_add+0xc9/0x650 -------------------8<--------------------------------------- Instead of relying on guest applications to release all references to the ports, we should go ahead and unregister the port from all the core layers. Any open/read calls on the port will then just return errors, and an unplug/plug operation on the host will succeed as expected. This also caused buggy behaviour in case of the device removal (not just a port): when the device was removed (which means all ports on that device are removed automatically as well), the ports with active users would clean up only when the last references were dropped -- and it would be too late then to be referencing char device pointers, resulting in oopses: -------------------8<--------------------------------------- PID: 6162 TASK: ffff8801147ad500 CPU: 0 COMMAND: "cat" #0 [ffff88011b9d5a90] machine_kexec at ffffffff8103232b #1 [ffff88011b9d5af0] crash_kexec at ffffffff810b9322 #2 [ffff88011b9d5bc0] oops_end at ffffffff814f4a50 #3 [ffff88011b9d5bf0] die at ffffffff8100f26b #4 [ffff88011b9d5c20] do_general_protection at ffffffff814f45e2 #5 [ffff88011b9d5c50] general_protection at ffffffff814f3db5 [exception RIP: strlen+2] RIP: ffffffff81272ae2 RSP: ffff88011b9d5d00 RFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff880118901c18 RCX: 0000000000000000 RDX: ffff88011799982c RSI: 00000000000000d0 RDI: 3a303030302f3030 RBP: ffff88011b9d5d38 R8: 0000000000000006 R9: ffffffffa0134500 R10: 0000000000001000 R11: 0000000000001000 R12: ffff880117a1cc10 R13: 00000000000000d0 R14: 0000000000000017 R15: ffffffff81aff700 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #6 [ffff88011b9d5d00] kobject_get_path at ffffffff8126dc5d #7 [ffff88011b9d5d40] kobject_uevent_env at ffffffff8126e551 #8 [ffff88011b9d5dd0] kobject_uevent at ffffffff8126e9eb #9 [ffff88011b9d5de0] device_del at ffffffff813440c7 -------------------8<--------------------------------------- So clean up when we have all the context, and all that's left to do when the references to the port have dropped is to free up the port struct itself. CC: <stable@vger.kernel.org> Reported-by: chayang <chayang@redhat.com> Reported-by: YOGANANTH SUBRAMANIAN <anantyog@in.ibm.com> Reported-by: FuXiangChun <xfu@redhat.com> Reported-by: Qunfang Zhang <qzhang@redhat.com> Reported-by: Sibiao Luo <sluo@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
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In several places, this snippet is used when removing neigh entries: list_del(&neigh->list); ipoib_neigh_free(neigh); The list_del() removes neigh from the associated struct ipoib_path, while ipoib_neigh_free() removes neigh from the device's neigh entry lookup table. Both of these operations are protected by the priv->lock spinlock. The table however is also protected via RCU, and so naturally the lock is not held when doing reads. This leads to a race condition, in which a thread may successfully look up a neigh entry that has already been deleted from neigh->list. Since the previous deletion will have marked the entry with poison, a second list_del() on the object will cause a panic: #5 [ffff8802338c3c70] general_protection at ffffffff815108c5 [exception RIP: list_del+16] RIP: ffffffff81289020 RSP: ffff8802338c3d20 RFLAGS: 00010082 RAX: dead000000200200 RBX: ffff880433e60c88 RCX: 0000000000009e6c RDX: 0000000000000246 RSI: ffff8806012ca298 RDI: ffff880433e60c88 RBP: ffff8802338c3d30 R8: ffff8806012ca2e8 R9: 00000000ffffffff R10: 0000000000000001 R11: 0000000000000000 R12: ffff8804346b2020 R13: ffff88032a3e7540 R14: ffff8804346b26e0 R15: 0000000000000246 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0000 #6 [ffff8802338c3d38] ipoib_cm_tx_handler at ffffffffa066fe0a [ib_ipoib] #7 [ffff8802338c3d98] cm_process_work at ffffffffa05149a7 [ib_cm] #8 [ffff8802338c3de8] cm_work_handler at ffffffffa05161aa [ib_cm] #9 [ffff8802338c3e38] worker_thread at ffffffff81090e10 torvalds#10 [ffff8802338c3ee8] kthread at ffffffff81096c66 torvalds#11 [ffff8802338c3f48] kernel_thread at ffffffff8100c0ca We move the list_del() into ipoib_neigh_free(), so that deletion happens only once, after the entry has been successfully removed from the lookup table. This same behavior is already used in ipoib_del_neighs_by_gid() and __ipoib_reap_neigh(). Signed-off-by: Jim Foraker <foraker1@llnl.gov> Reviewed-by: Or Gerlitz <ogerlitz@mellanox.com> Reviewed-by: Jack Wang <jinpu.wang@profitbricks.com> Reviewed-by: Shlomo Pongratz <shlomop@mellanox.com> Signed-off-by: Roland Dreier <roland@purestorage.com>
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When 2 devices are registered at the same time, in Part 2 both will get the same minor number, making Part6 crash, because it cannot create a create a device with a duplicated minor: [ 7.157648] ------------[ cut here ]------------ [ 7.157666] WARNING: at fs/sysfs/dir.c:530 sysfs_add_one+0xbd/0xe0() [ 7.157669] sysfs: cannot create duplicate filename '/dev/char/81:1' [ 7.157672] Modules linked in: qtec_xform(+) qt5023_video(+) videobuf2_vmalloc videobuf2_dma_sg videobuf2_memops videobuf2_core gpio_xilinx(+) qtec_white qtec_cmosis(+) qtec_pcie qt5023 [ 7.157694] CPU: 0 PID: 120 Comm: systemd-udevd Not tainted 3.10.0-qtec-standard #8 [ 7.157698] Hardware name: QTechnology QT5022/QT5022, BIOS PM_2.1.0.309 X64 05/23/2013 [ 7.157702] 0000000000000009 ffff8801788358e8 ffffffff8176c487 ffff880178835928 [ 7.157707] ffffffff8106f6f0 ffff880175759770 00000000ffffffef ffff880175759930 [ 7.157712] ffff8801788359e8 ffff880178bff000 ffff880175759930 ffff880178835988 [ 7.157718] Call Trace: [ 7.157728] [<ffffffff8176c487>] dump_stack+0x19/0x1b [ 7.157735] [<ffffffff8106f6f0>] warn_slowpath_common+0x70/0xa0 [ 7.157740] [<ffffffff8106f7d6>] warn_slowpath_fmt+0x46/0x50 [ 7.157746] [<ffffffff81324b35>] ? strlcat+0x65/0x90 [ 7.157750] [<ffffffff811d516d>] sysfs_add_one+0xbd/0xe0 [ 7.157755] [<ffffffff811d5c6b>] sysfs_do_create_link_sd+0xdb/0x200 [ 7.157760] [<ffffffff811d5db1>] sysfs_create_link+0x21/0x40 [ 7.157765] [<ffffffff813e277b>] device_add+0x21b/0x6d0 [ 7.157772] [<ffffffff813f2985>] ? pm_runtime_init+0xe5/0xf0 [ 7.157776] [<ffffffff813e2c4e>] device_register+0x1e/0x30 [ 7.157782] [<ffffffff8153e8c3>] __video_register_device+0x313/0x610 [ 7.157791] [<ffffffffa00957c5>] qtec_xform_probe+0x465/0x7a4 [qtec_xform] [ 7.157797] [<ffffffff813e7b13>] platform_drv_probe+0x43/0x80 [ 7.157802] [<ffffffff813e531a>] ? driver_sysfs_add+0x7a/0xb0 [ 7.157807] [<ffffffff813e584b>] driver_probe_device+0x8b/0x3a0 [ 7.157812] [<ffffffff813e5c0b>] __driver_attach+0xab/0xb0 [ 7.157816] [<ffffffff813e5b60>] ? driver_probe_device+0x3a0/0x3a0 [ 7.157820] [<ffffffff813e37fd>] bus_for_each_dev+0x5d/0xa0 [ 7.157825] [<ffffffff813e529e>] driver_attach+0x1e/0x20 [ 7.157829] [<ffffffff813e4d3e>] bus_add_driver+0x10e/0x280 [ 7.157833] [<ffffffffa0099000>] ? 0xffffffffa0098fff [ 7.157837] [<ffffffffa0099000>] ? 0xffffffffa0098fff [ 7.157842] [<ffffffff813e6317>] driver_register+0x77/0x170 [ 7.157848] [<ffffffff81151bcc>] ? __vunmap+0x9c/0x110 [ 7.157852] [<ffffffffa0099000>] ? 0xffffffffa0098fff [ 7.157857] [<ffffffff813e7236>] platform_driver_register+0x46/0x50 [ 7.157863] [<ffffffffa0099010>] qtec_xform_plat_driver_init+0x10/0x12 [qtec_xform] [ 7.157869] [<ffffffff810002ea>] do_one_initcall+0xea/0x1a0 [ 7.157875] [<ffffffff810cf1f1>] load_module+0x1a91/0x2630 [ 7.157880] [<ffffffff8133bee0>] ? ddebug_proc_show+0xe0/0xe0 [ 7.157887] [<ffffffff817760f2>] ? page_fault+0x22/0x30 [ 7.157892] [<ffffffff810cfe7a>] SyS_init_module+0xea/0x140 [ 7.157898] [<ffffffff8177e5b9>] tracesys+0xd0/0xd5 [ 7.157902] ---[ end trace 660cc3a65a4bf01b ]--- [ 7.157939] __video_register_device: device_register failed Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com> Acked-by: Sakari Ailus <sakari.ailus@iki.fi> Acked-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
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Sep 22, 2013
When booting secondary CPUs, announce_cpu() is called to show which cpu has been brought up. For example: [ 0.402751] smpboot: Booting Node 0, Processors #1 #2 #3 #4 #5 OK [ 0.525667] smpboot: Booting Node 1, Processors #6 #7 #8 #9 torvalds#10 torvalds#11 OK [ 0.755592] smpboot: Booting Node 0, Processors torvalds#12 torvalds#13 torvalds#14 torvalds#15 torvalds#16 torvalds#17 OK [ 0.890495] smpboot: Booting Node 1, Processors torvalds#18 torvalds#19 torvalds#20 torvalds#21 torvalds#22 torvalds#23 But the last "OK" is lost, because 'nr_cpu_ids-1' represents the maximum possible cpu id. It should use the maximum present cpu id in case not all CPUs booted up. Signed-off-by: Libin <huawei.libin@huawei.com> Cc: <guohanjun@huawei.com> Cc: <wangyijing@huawei.com> Cc: <fenghua.yu@intel.com> Cc: <paul.gortmaker@windriver.com> Link: http://lkml.kernel.org/r/1378378676-18276-1-git-send-email-huawei.libin@huawei.com [ tweaked the changelog, removed unnecessary line break, tweaked the format to align the fields vertically. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Enable only those interrupts that we can handle & acknowledge in the interrupt handler. At least on EdgeRouter Lite, the hardware may occasionally interrupt with some error condition when the physical link status changes frequently. Since the interrupt condition is not acked properly, this leads to the following warning and the IRQ gets disabled completely: [ 41.324700] eth0: Link down [ 44.324721] eth0: 1000 Mbps Full duplex, port 0, queue 0 [ 44.885590] irq 117: nobody cared (try booting with the "irqpoll" option) [ 44.892397] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.11.0-rc5-edge-los.git-27d042f-dirty-00950-gaa42f2d-dirty #8 [ 44.902825] Stack : ffffffff815c0000 0000000000000004 0000000000000003 0000000000000000 ffffffff81fd0000 ffffffff815c0000 0000000000000004 ffffffff8118530c ffffffff815c0000 ffffffff811858d8 0000000000000000 0000000000000000 ffffffff81fd0000 ffffffff81fc0000 ffffffff8152f3a0 ffffffff815b7bf7 ffffffff81fc6688 ffffffff815b8060 0000000000000000 0000000000000000 0000000000000000 ffffffff815346c8 ffffffff815346b0 ffffffff814a6a18 ffffffff8158b848 ffffffff81145614 ffffffff81593800 ffffffff81187174 ffffffff815b7d00 ffffffff8158b760 0000000000000000 ffffffff814a9184 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 ffffffff811203b8 0000000000000000 0000000000000000 ... [ 44.968408] Call Trace: [ 44.970873] [<ffffffff811203b8>] show_stack+0x68/0x80 [ 44.975937] [<ffffffff814a9184>] dump_stack+0x78/0xb8 [ 44.980999] [<ffffffff811aac54>] __report_bad_irq+0x44/0x108 [ 44.986662] [<ffffffff811ab238>] note_interrupt+0x248/0x2a0 [ 44.992240] [<ffffffff811a85e4>] handle_irq_event_percpu+0x144/0x200 [ 44.998598] [<ffffffff811a86f4>] handle_irq_event+0x54/0x90 [ 45.004176] [<ffffffff811ab908>] handle_level_irq+0xd0/0x148 [ 45.009839] [<ffffffff811a7b04>] generic_handle_irq+0x34/0x50 [ 45.015589] [<ffffffff8111dae8>] do_IRQ+0x18/0x30 [ 45.020301] [<ffffffff8110486c>] plat_irq_dispatch+0x74/0xb8 [ 45.025958] [ 45.027451] handlers: [ 45.029731] [<ffffffff813fca10>] cvm_oct_rgmii_rml_interrupt [ 45.035397] Disabling IRQ torvalds#117 [ 45.038742] Port 0 receive error code 13, packet dropped [ 46.324719] eth0: Link down [ 48.324733] eth0: 1000 Mbps Full duplex, port 0, queue 0 Reported-by: "Jason A. Donenfeld" <Jason@zx2c4.com> Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi> Acked-by: David Daney <david.daney@cavium.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: devel@driverdev.osuosl.org Cc: linux-mips@linux-mips.org Cc: Jason A. Donenfeld <Jason@zx2c4.com> Cc: richard@nod.at Patchwork: https://patchwork.linux-mips.org/patch/5810/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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Oct 28, 2013
Enable only those interrupts that we can handle & acknowledge in the interrupt handler. At least on EdgeRouter Lite, the hardware may occasionally interrupt with some error condition when the physical link status changes frequently. Since the interrupt condition is not acked properly, this leads to the following warning and the IRQ gets disabled completely: [ 41.324700] eth0: Link down [ 44.324721] eth0: 1000 Mbps Full duplex, port 0, queue 0 [ 44.885590] irq 117: nobody cared (try booting with the "irqpoll" option) [ 44.892397] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.11.0-rc5-edge-los.git-27d042f-dirty-00950-gaa42f2d-dirty #8 [ 44.902825] Stack : ffffffff815c0000 0000000000000004 0000000000000003 0000000000000000 ffffffff81fd0000 ffffffff815c0000 0000000000000004 ffffffff8118530c ffffffff815c0000 ffffffff811858d8 0000000000000000 0000000000000000 ffffffff81fd0000 ffffffff81fc0000 ffffffff8152f3a0 ffffffff815b7bf7 ffffffff81fc6688 ffffffff815b8060 0000000000000000 0000000000000000 0000000000000000 ffffffff815346c8 ffffffff815346b0 ffffffff814a6a18 ffffffff8158b848 ffffffff81145614 ffffffff81593800 ffffffff81187174 ffffffff815b7d00 ffffffff8158b760 0000000000000000 ffffffff814a9184 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 ffffffff811203b8 0000000000000000 0000000000000000 ... [ 44.968408] Call Trace: [ 44.970873] [<ffffffff811203b8>] show_stack+0x68/0x80 [ 44.975937] [<ffffffff814a9184>] dump_stack+0x78/0xb8 [ 44.980999] [<ffffffff811aac54>] __report_bad_irq+0x44/0x108 [ 44.986662] [<ffffffff811ab238>] note_interrupt+0x248/0x2a0 [ 44.992240] [<ffffffff811a85e4>] handle_irq_event_percpu+0x144/0x200 [ 44.998598] [<ffffffff811a86f4>] handle_irq_event+0x54/0x90 [ 45.004176] [<ffffffff811ab908>] handle_level_irq+0xd0/0x148 [ 45.009839] [<ffffffff811a7b04>] generic_handle_irq+0x34/0x50 [ 45.015589] [<ffffffff8111dae8>] do_IRQ+0x18/0x30 [ 45.020301] [<ffffffff8110486c>] plat_irq_dispatch+0x74/0xb8 [ 45.025958] [ 45.027451] handlers: [ 45.029731] [<ffffffff813fca10>] cvm_oct_rgmii_rml_interrupt [ 45.035397] Disabling IRQ torvalds#117 [ 45.038742] Port 0 receive error code 13, packet dropped [ 46.324719] eth0: Link down [ 48.324733] eth0: 1000 Mbps Full duplex, port 0, queue 0 Reported-by: "Jason A. Donenfeld" <Jason@zx2c4.com> Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi> Acked-by: David Daney <david.daney@cavium.com> Acked-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Oct 28, 2013
When parsing lines from objdump a line containing source code starting with a numeric label is mistaken for a line of disassembly starting with a memory address. Current validation fails to recognise that the "memory address" is out of range and calculates an invalid offset which later causes this segfault: Program received signal SIGSEGV, Segmentation fault. 0x0000000000457315 in disasm__calc_percent (notes=0xc98970, evidx=0, offset=143705, end=2127526177, path=0x7fffffffbf50) at util/annotate.c:631 631 hits += h->addr[offset++]; (gdb) bt #0 0x0000000000457315 in disasm__calc_percent (notes=0xc98970, evidx=0, offset=143705, end=2127526177, path=0x7fffffffbf50) at util/annotate.c:631 #1 0x00000000004d65e3 in annotate_browser__calc_percent (browser=0x7fffffffd130, evsel=0xa01da0) at ui/browsers/annotate.c:364 #2 0x00000000004d7433 in annotate_browser__run (browser=0x7fffffffd130, evsel=0xa01da0, hbt=0x0) at ui/browsers/annotate.c:672 #3 0x00000000004d80c9 in symbol__tui_annotate (sym=0xc989a0, map=0xa02660, evsel=0xa01da0, hbt=0x0) at ui/browsers/annotate.c:962 #4 0x00000000004d7aa0 in hist_entry__tui_annotate (he=0xdf73f0, evsel=0xa01da0, hbt=0x0) at ui/browsers/annotate.c:823 #5 0x00000000004dd648 in perf_evsel__hists_browse (evsel=0xa01da0, nr_events=1, helpline= 0x58b768 "For a higher level overview, try: perf report --sort comm,dso", ev_name=0xa02cd0 "cycles", left_exits=false, hbt= 0x0, min_pcnt=0, env=0xa011e0) at ui/browsers/hists.c:1659 #6 0x00000000004de372 in perf_evlist__tui_browse_hists (evlist=0xa01520, help= 0x58b768 "For a higher level overview, try: perf report --sort comm,dso", hbt=0x0, min_pcnt=0, env=0xa011e0) at ui/browsers/hists.c:1950 #7 0x000000000042cf6b in __cmd_report (rep=0x7fffffffd6c0) at builtin-report.c:581 #8 0x000000000042e25d in cmd_report (argc=0, argv=0x7fffffffe4b0, prefix=0x0) at builtin-report.c:965 #9 0x000000000041a0e1 in run_builtin (p=0x801548, argc=1, argv=0x7fffffffe4b0) at perf.c:319 torvalds#10 0x000000000041a319 in handle_internal_command (argc=1, argv=0x7fffffffe4b0) at perf.c:376 torvalds#11 0x000000000041a465 in run_argv (argcp=0x7fffffffe38c, argv=0x7fffffffe380) at perf.c:420 torvalds#12 0x000000000041a707 in main (argc=1, argv=0x7fffffffe4b0) at perf.c:521 After the fix is applied the symbol can be annotated showing the problematic line "1: rep" copy_user_generic_string /usr/lib/debug/lib/modules/3.9.10-100.fc17.x86_64/vmlinux */ ENTRY(copy_user_generic_string) CFI_STARTPROC ASM_STAC andl %edx,%edx and %edx,%edx jz 4f je 37 cmpl $8,%edx cmp $0x8,%edx jb 2f /* less than 8 bytes, go to byte copy loop */ jb 33 ALIGN_DESTINATION mov %edi,%ecx and $0x7,%ecx je 28 sub $0x8,%ecx neg %ecx sub %ecx,%edx 1a: mov (%rsi),%al mov %al,(%rdi) inc %rsi inc %rdi dec %ecx jne 1a movl %edx,%ecx 28: mov %edx,%ecx shrl $3,%ecx shr $0x3,%ecx andl $7,%edx and $0x7,%edx 1: rep 100.00 rep movsq %ds:(%rsi),%es:(%rdi) movsq 2: movl %edx,%ecx 33: mov %edx,%ecx 3: rep rep movsb %ds:(%rsi),%es:(%rdi) movsb 4: xorl %eax,%eax 37: xor %eax,%eax data32 xchg %ax,%ax ASM_CLAC ret retq Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1379009721-27667-1-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The crash[1] is found by xfstests/generic/208 with "-o compress", it's not reproduced everytime, but it does panic. The bug is quite interesting, it's actually introduced by a recent commit (573aeca, Btrfs: actually limit the size of delalloc range). Btrfs implements delay allocation, so during writeback, we (1) get a page A and lock it (2) search the state tree for delalloc bytes and lock all pages within the range (3) process the delalloc range, including find disk space and create ordered extent and so on. (4) submit the page A. It runs well in normal cases, but if we're in a racy case, eg. buffered compressed writes and aio-dio writes, sometimes we may fail to lock all pages in the 'delalloc' range, in which case, we need to fall back to search the state tree again with a smaller range limit(max_bytes = PAGE_CACHE_SIZE - offset). The mentioned commit has a side effect, that is, in the fallback case, we can find delalloc bytes before the index of the page we already have locked, so we're in the case of (delalloc_end <= *start) and return with (found > 0). This ends with not locking delalloc pages but making ->writepage still process them, and the crash happens. This fixes it by just thinking that we find nothing and returning to caller as the caller knows how to deal with it properly. [1]: ------------[ cut here ]------------ kernel BUG at mm/page-writeback.c:2170! [...] CPU: 2 PID: 11755 Comm: btrfs-delalloc- Tainted: G O 3.11.0+ #8 [...] RIP: 0010:[<ffffffff810f5093>] [<ffffffff810f5093>] clear_page_dirty_for_io+0x1e/0x83 [...] [ 4934.248731] Stack: [ 4934.248731] ffff8801477e5dc8 ffffea00049b9f00 ffff8801869f9ce8 ffffffffa02b841a [ 4934.248731] 0000000000000000 0000000000000000 0000000000000fff 0000000000000620 [ 4934.248731] ffff88018db59c78 ffffea0005da8d40 ffffffffa02ff860 00000001810016c0 [ 4934.248731] Call Trace: [ 4934.248731] [<ffffffffa02b841a>] extent_range_clear_dirty_for_io+0xcf/0xf5 [btrfs] [ 4934.248731] [<ffffffffa02a8889>] compress_file_range+0x1dc/0x4cb [btrfs] [ 4934.248731] [<ffffffff8104f7af>] ? detach_if_pending+0x22/0x4b [ 4934.248731] [<ffffffffa02a8bad>] async_cow_start+0x35/0x53 [btrfs] [ 4934.248731] [<ffffffffa02c694b>] worker_loop+0x14b/0x48c [btrfs] [ 4934.248731] [<ffffffffa02c6800>] ? btrfs_queue_worker+0x25c/0x25c [btrfs] [ 4934.248731] [<ffffffff810608f5>] kthread+0x8d/0x95 [ 4934.248731] [<ffffffff81060868>] ? kthread_freezable_should_stop+0x43/0x43 [ 4934.248731] [<ffffffff814fe09c>] ret_from_fork+0x7c/0xb0 [ 4934.248731] [<ffffffff81060868>] ? kthread_freezable_should_stop+0x43/0x43 [ 4934.248731] Code: ff 85 c0 0f 94 c0 0f b6 c0 59 5b 5d c3 0f 1f 44 00 00 55 48 89 e5 41 54 53 48 89 fb e8 2c de 00 00 49 89 c4 48 8b 03 a8 01 75 02 <0f> 0b 4d 85 e4 74 52 49 8b 84 24 80 00 00 00 f6 40 20 01 75 44 [ 4934.248731] RIP [<ffffffff810f5093>] clear_page_dirty_for_io+0x1e/0x83 [ 4934.248731] RSP <ffff8801869f9c48> [ 4934.280307] ---[ end trace 36f06d3f8750236a ]--- Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
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…CIe cards The band selection and PE control code for the RT3593 chipsets only handles USB based devices currently. Due to this limitation RT3593 based PCIe cards are not working correctly. On PCIe cards band selection is controlled via GPIO #8 which is identical to the USB devices. The LNA PE control is slightly different, all LNA PEs are controlled by GPIO #4. Update the code to configure the GPIO_CTRL register correctly on PCIe devices. Cc: Steven Liu <steven.liu@mediatek.com> Cc: JasonYS Cheng <jasonys.cheng@mediatek.com> Signed-off-by: Gabor Juhos <juhosg@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
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As the new x86 CPU bootup printout format code maintainer, I am taking immediate action to improve and clean (and thus indulge my OCD) the reporting of the cores when coming up online. Fix padding to a right-hand alignment, cleanup code and bind reporting width to the max number of supported CPUs on the system, like this: [ 0.074509] smpboot: Booting Node 0, Processors: #1 #2 #3 #4 #5 #6 #7 OK [ 0.644008] smpboot: Booting Node 1, Processors: #8 #9 torvalds#10 torvalds#11 torvalds#12 torvalds#13 torvalds#14 torvalds#15 OK [ 1.245006] smpboot: Booting Node 2, Processors: torvalds#16 torvalds#17 torvalds#18 torvalds#19 torvalds#20 torvalds#21 torvalds#22 torvalds#23 OK [ 1.864005] smpboot: Booting Node 3, Processors: torvalds#24 torvalds#25 torvalds#26 torvalds#27 torvalds#28 torvalds#29 torvalds#30 torvalds#31 OK [ 2.489005] smpboot: Booting Node 4, Processors: torvalds#32 torvalds#33 torvalds#34 torvalds#35 torvalds#36 torvalds#37 torvalds#38 torvalds#39 OK [ 3.093005] smpboot: Booting Node 5, Processors: torvalds#40 torvalds#41 torvalds#42 torvalds#43 torvalds#44 torvalds#45 torvalds#46 torvalds#47 OK [ 3.698005] smpboot: Booting Node 6, Processors: torvalds#48 torvalds#49 torvalds#50 torvalds#51 #52 #53 torvalds#54 torvalds#55 OK [ 4.304005] smpboot: Booting Node 7, Processors: torvalds#56 torvalds#57 #58 torvalds#59 torvalds#60 torvalds#61 torvalds#62 torvalds#63 OK [ 4.961413] Brought up 64 CPUs and this: [ 0.072367] smpboot: Booting Node 0, Processors: #1 #2 #3 #4 #5 #6 #7 OK [ 0.686329] Brought up 8 CPUs Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Libin <huawei.libin@huawei.com> Cc: wangyijing@huawei.com Cc: fenghua.yu@intel.com Cc: guohanjun@huawei.com Cc: paul.gortmaker@windriver.com Link: http://lkml.kernel.org/r/20130927143554.GF4422@pd.tnic Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Turn it into (for example): [ 0.073380] x86: Booting SMP configuration: [ 0.074005] .... node #0, CPUs: #1 #2 #3 #4 #5 #6 #7 [ 0.603005] .... node #1, CPUs: #8 #9 torvalds#10 torvalds#11 torvalds#12 torvalds#13 torvalds#14 torvalds#15 [ 1.200005] .... node #2, CPUs: torvalds#16 torvalds#17 torvalds#18 torvalds#19 torvalds#20 torvalds#21 torvalds#22 torvalds#23 [ 1.796005] .... node #3, CPUs: torvalds#24 torvalds#25 torvalds#26 torvalds#27 torvalds#28 torvalds#29 torvalds#30 torvalds#31 [ 2.393005] .... node #4, CPUs: torvalds#32 torvalds#33 torvalds#34 torvalds#35 torvalds#36 torvalds#37 torvalds#38 torvalds#39 [ 2.996005] .... node #5, CPUs: torvalds#40 torvalds#41 torvalds#42 torvalds#43 torvalds#44 torvalds#45 torvalds#46 torvalds#47 [ 3.600005] .... node #6, CPUs: torvalds#48 torvalds#49 torvalds#50 torvalds#51 #52 #53 torvalds#54 torvalds#55 [ 4.202005] .... node #7, CPUs: torvalds#56 torvalds#57 #58 torvalds#59 torvalds#60 torvalds#61 torvalds#62 torvalds#63 [ 4.811005] .... node #8, CPUs: torvalds#64 torvalds#65 torvalds#66 torvalds#67 torvalds#68 torvalds#69 #70 torvalds#71 [ 5.421006] .... node #9, CPUs: torvalds#72 torvalds#73 torvalds#74 torvalds#75 torvalds#76 torvalds#77 torvalds#78 torvalds#79 [ 6.032005] .... node torvalds#10, CPUs: torvalds#80 torvalds#81 torvalds#82 torvalds#83 torvalds#84 torvalds#85 torvalds#86 torvalds#87 [ 6.648006] .... node torvalds#11, CPUs: torvalds#88 torvalds#89 torvalds#90 torvalds#91 torvalds#92 torvalds#93 torvalds#94 torvalds#95 [ 7.262005] .... node torvalds#12, CPUs: torvalds#96 torvalds#97 torvalds#98 torvalds#99 torvalds#100 torvalds#101 torvalds#102 torvalds#103 [ 7.865005] .... node torvalds#13, CPUs: torvalds#104 torvalds#105 torvalds#106 torvalds#107 torvalds#108 torvalds#109 torvalds#110 torvalds#111 [ 8.466005] .... node torvalds#14, CPUs: torvalds#112 torvalds#113 torvalds#114 torvalds#115 torvalds#116 torvalds#117 torvalds#118 torvalds#119 [ 9.073006] .... node torvalds#15, CPUs: torvalds#120 torvalds#121 torvalds#122 torvalds#123 torvalds#124 torvalds#125 torvalds#126 torvalds#127 [ 9.679901] x86: Booted up 16 nodes, 128 CPUs and drop useless elements. Change num_digits() to hpa's division-avoiding, cell-phone-typed version which he went at great lengths and pains to submit on a Saturday evening. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: huawei.libin@huawei.com Cc: wangyijing@huawei.com Cc: fenghua.yu@intel.com Cc: guohanjun@huawei.com Cc: paul.gortmaker@windriver.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20130930095624.GB16383@pd.tnic Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Andrey reported the following report: ERROR: AddressSanitizer: heap-buffer-overflow on address ffff8800359c99f3 ffff8800359c99f3 is located 0 bytes to the right of 243-byte region [ffff8800359c9900, ffff8800359c99f3) Accessed by thread T13003: #0 ffffffff810dd2da (asan_report_error+0x32a/0x440) #1 ffffffff810dc6b0 (asan_check_region+0x30/0x40) #2 ffffffff810dd4d3 (__tsan_write1+0x13/0x20) #3 ffffffff811cd19e (ftrace_regex_release+0x1be/0x260) #4 ffffffff812a1065 (__fput+0x155/0x360) #5 ffffffff812a12de (____fput+0x1e/0x30) #6 ffffffff8111708d (task_work_run+0x10d/0x140) #7 ffffffff810ea043 (do_exit+0x433/0x11f0) #8 ffffffff810eaee4 (do_group_exit+0x84/0x130) #9 ffffffff810eafb1 (SyS_exit_group+0x21/0x30) torvalds#10 ffffffff81928782 (system_call_fastpath+0x16/0x1b) Allocated by thread T5167: #0 ffffffff810dc778 (asan_slab_alloc+0x48/0xc0) #1 ffffffff8128337c (__kmalloc+0xbc/0x500) #2 ffffffff811d9d54 (trace_parser_get_init+0x34/0x90) #3 ffffffff811cd7b3 (ftrace_regex_open+0x83/0x2e0) #4 ffffffff811cda7d (ftrace_filter_open+0x2d/0x40) #5 ffffffff8129b4ff (do_dentry_open+0x32f/0x430) #6 ffffffff8129b668 (finish_open+0x68/0xa0) #7 ffffffff812b66ac (do_last+0xb8c/0x1710) #8 ffffffff812b7350 (path_openat+0x120/0xb50) #9 ffffffff812b8884 (do_filp_open+0x54/0xb0) torvalds#10 ffffffff8129d36c (do_sys_open+0x1ac/0x2c0) torvalds#11 ffffffff8129d4b7 (SyS_open+0x37/0x50) torvalds#12 ffffffff81928782 (system_call_fastpath+0x16/0x1b) Shadow bytes around the buggy address: ffff8800359c9700: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd ffff8800359c9780: fd fd fd fd fd fd fd fd fa fa fa fa fa fa fa fa ffff8800359c9800: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa ffff8800359c9880: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa ffff8800359c9900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 =>ffff8800359c9980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00[03]fb ffff8800359c9a00: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa ffff8800359c9a80: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa ffff8800359c9b00: fa fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00 ffff8800359c9b80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8800359c9c00: 00 00 00 00 00 00 00 00 fa fa fa fa fa fa fa fa Shadow byte legend (one shadow byte represents 8 application bytes): Addressable: 00 Partially addressable: 01 02 03 04 05 06 07 Heap redzone: fa Heap kmalloc redzone: fb Freed heap region: fd Shadow gap: fe The out-of-bounds access happens on 'parser->buffer[parser->idx] = 0;' Although the crash happened in ftrace_regex_open() the real bug occurred in trace_get_user() where there's an incrementation to parser->idx without a check against the size. The way it is triggered is if userspace sends in 128 characters (EVENT_BUF_SIZE + 1), the loop that reads the last character stores it and then breaks out because there is no more characters. Then the last character is read to determine what to do next, and the index is incremented without checking size. Then the caller of trace_get_user() usually nulls out the last character with a zero, but since the index is equal to the size, it writes a nul character after the allocated space, which can corrupt memory. Luckily, only root user has write access to this file. Link: http://lkml.kernel.org/r/20131009222323.04fd1a0d@gandalf.local.home Reported-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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…ux/kernel/git/tip/tip Pull x86 boot changes from Ingo Molnar: "Two changes that prettify and compactify the SMP bootup output from: smpboot: Booting Node 0, Processors #1 #2 #3 OK smpboot: Booting Node 1, Processors #4 #5 #6 #7 OK smpboot: Booting Node 2, Processors #8 #9 torvalds#10 torvalds#11 OK smpboot: Booting Node 3, Processors torvalds#12 torvalds#13 torvalds#14 torvalds#15 OK Brought up 16 CPUs to something like: x86: Booting SMP configuration: .... node #0, CPUs: #1 #2 #3 .... node #1, CPUs: #4 #5 #6 #7 .... node #2, CPUs: #8 #9 torvalds#10 torvalds#11 .... node #3, CPUs: torvalds#12 torvalds#13 torvalds#14 torvalds#15 x86: Booted up 4 nodes, 16 CPUs" * 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/boot: Further compress CPUs bootup message x86: Improve the printout of the SMP bootup CPU table
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the 'soc' node in the common .dtsi for MPC5121 has an '#interrupt-cells' property although this node is not an interrupt controller remove this erroneously placed property because starting with v3.13-rc1 lookup and resolution of 'interrupts' specs for peripherals gets misled, emits 'no irq domain found' WARN() messages and breaks the boot process irq: no irq domain found for /soc@80000000 ! ------------[ cut here ]------------ WARNING: at drivers/of/platform.c:171 Modules linked in: CPU: 0 PID: 1 Comm: swapper Tainted: G W 3.13.0-rc1-00001-g8a66234 #8 task: df823bb0 ti: df834000 task.ti: df834000 NIP: c02b5190 LR: c02b5180 CTR: c01cf4e0 REGS: df835c50 TRAP: 0700 Tainted: G W (3.13.0-rc1-00001-g8a66234) MSR: 00029032 <EE,ME,IR,DR,RI> CR: 229a9d42 XER: 20000000 GPR00: c02b5180 df835d00 df823bb0 00000000 00000000 df835b18 ffffffff 00000308 GPR08: c0479cc0 c0480000 c0479cc0 00000308 00000308 00000000 c00040fc 00000000 GPR16: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 df850880 GPR24: df84d670 00000000 00000001 df8561a dffffccc df85089c 00000020 00000001 NIP [c02b5190] of_device_alloc+0xf4/0x1a0 LR [c02b5180] of_device_alloc+0xe4/0x1a0 Call Trace: [df835d00] [c02b5180] of_device_alloc+0xe4/0x1a0 (unreliable) [df835d50] [c02b5278] of_platform_device_create_pdata+0x3c/0xc8 [df835d70] [c02b53fc] of_platform_bus_create+0xf8/0x170 [df835dc0] [c02b5448] of_platform_bus_create+0x144/0x170 [df835e10] [c02b55a8] of_platform_bus_probe+0x98/0xe8 [df835e30] [c0437508] mpc512x_init+0x28/0x1c4 [df835e7] [c0435de8] ppc_init+0x4c/0x60 [df835e80] [c0003b28] do_one_initcall+0x150/0x1a4 [df835ef0] [c0432048] kernel_init_freeable+0x114/0x1c0 [df835f30] [c0004114] kernel_init+0x18/0x124 [df835f40] [c000e910] ret_from_kernel_thread+0x5c/0x64 Instruction dump: 409effd4 57c9103a 57de2834 7c89f050 7f83e378 7c972214 7f45d378 48001f55 7c63d278 7c630034 5463d97e 687a0001 <0f1a0000> 2f990000 387b0010 939b0098 ---[ end trace 2257f10e5a20cbdd ]--- ... irq: no irq domain found for /soc@80000000 ! fsl-diu-fb 80002100.display: could not get DIU IRQ fsl-diu-fb: probe of 80002100.display failed with error -22 irq: no irq domain found for /soc@80000000 ! mpc512x_dma 80014000.dma: Error mapping IRQ! mpc512x_dma: probe of 80014000.dma failed with error -22 ... irq: no irq domain found for /soc@80000000 ! fs_enet: probe of 80002800.ethernet failed with error -22 ... irq: no irq domain found for /soc@80000000 ! mpc5121-rtc 80000a00.rtc: mpc5121_rtc_probe: could not request irq: 0 mpc5121-rtc: probe of 80000a00.rtc failed with error -22 ... Cc: Anatolij Gustschin <agust@denx.de> Cc: linuxppc-dev@lists.ozlabs.org Cc: devicetree@vger.kernel.org Signed-off-by: Gerhard Sittig <gsi@denx.de> Signed-off-by: Anatolij Gustschin <agust@denx.de>
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Jan 16, 2014
Lockdep reported that there is a potential for deadlock because vcpu->arch.tbacct_lock is not irq-safe, and is sometimes taken inside the rq_lock (run-queue lock) in the scheduler, which is taken within interrupts. The lockdep splat looks like: ====================================================== [ INFO: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected ] 3.12.0-rc5-kvm+ #8 Not tainted ------------------------------------------------------ qemu-system-ppc/4803 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: (&(&vcpu->arch.tbacct_lock)->rlock){+.+...}, at: [<c0000000000947ac>] .kvmppc_core_vcpu_put_hv+0x2c/0xa0 and this task is already holding: (&rq->lock){-.-.-.}, at: [<c000000000ac16c0>] .__schedule+0x180/0xaa0 which would create a new lock dependency: (&rq->lock){-.-.-.} -> (&(&vcpu->arch.tbacct_lock)->rlock){+.+...} but this new dependency connects a HARDIRQ-irq-safe lock: (&rq->lock){-.-.-.} ... which became HARDIRQ-irq-safe at: [<c00000000013797c>] .lock_acquire+0xbc/0x190 [<c000000000ac3c74>] ._raw_spin_lock+0x34/0x60 [<c0000000000f8564>] .scheduler_tick+0x54/0x180 [<c0000000000c2610>] .update_process_times+0x70/0xa0 [<c00000000012cdfc>] .tick_periodic+0x3c/0xe0 [<c00000000012cec8>] .tick_handle_periodic+0x28/0xb0 [<c00000000001ef40>] .timer_interrupt+0x120/0x2e0 [<c000000000002868>] decrementer_common+0x168/0x180 [<c0000000001c7ca4>] .get_page_from_freelist+0x924/0xc10 [<c0000000001c8e00>] .__alloc_pages_nodemask+0x200/0xba0 [<c0000000001c9eb8>] .alloc_pages_exact_nid+0x68/0x110 [<c000000000f4c3ec>] .page_cgroup_init+0x1e0/0x270 [<c000000000f24480>] .start_kernel+0x3e0/0x4e4 [<c000000000009d30>] .start_here_common+0x20/0x70 to a HARDIRQ-irq-unsafe lock: (&(&vcpu->arch.tbacct_lock)->rlock){+.+...} ... which became HARDIRQ-irq-unsafe at: ... [<c00000000013797c>] .lock_acquire+0xbc/0x190 [<c000000000ac3c74>] ._raw_spin_lock+0x34/0x60 [<c0000000000946ac>] .kvmppc_core_vcpu_load_hv+0x2c/0x100 [<c00000000008394c>] .kvmppc_core_vcpu_load+0x2c/0x40 [<c000000000081000>] .kvm_arch_vcpu_load+0x10/0x30 [<c00000000007afd4>] .vcpu_load+0x64/0xd0 [<c00000000007b0f8>] .kvm_vcpu_ioctl+0x68/0x730 [<c00000000025530c>] .do_vfs_ioctl+0x4dc/0x7a0 [<c000000000255694>] .SyS_ioctl+0xc4/0xe0 [<c000000000009ee4>] syscall_exit+0x0/0x98 Some users have reported this deadlock occurring in practice, though the reports have been primarily on 3.10.x-based kernels. This fixes the problem by making tbacct_lock be irq-safe. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
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May 17, 2015
Add a u32 in struct wl1271 to make fields reg_ch_conf_last and reg_ch_conf_pending 64bit aligned. Without this, on 64bit ARM, wlcore_set_pending_regdomain_ch() will fail at the point it calls set_bit(ch_bit_idx, (long*)wl->reg_ch_conf_pending); Here is the error message while doing iw wlan0 scan or connect: [ 760.644782] wlcore: WL1271_ACX_INTR_DATA [ 760.648734] Unhandled fault: alignment fault (0x96000021) at 0xffffffc01bdc1b54 [ 760.656048] Internal error: : 96000021 [#1] PREEMPT SMP [ 760.661267] Modules linked in: arc4 wl18xx wlcore mac80211 cfg80211 wlcore_sdio ti_conf_wl18xx btwilink st_drv bluetooth rfkill [ 760.672824] CPU: 0 PID: 1514 Comm: irq/198-wl18xx Tainted: G W 3.10.52-wl-00204-gf704232-dirty #8 [ 760.682558] task: ffffffc01d956040 ti: ffffffc01bea4000 task.ti: ffffffc01bea4000 [ 760.690043] PC is at set_bit+0x14/0x30 [ 760.693806] LR is at wlcore_set_pending_regdomain_ch+0x38/0x44 [wlcore] Signed-off-by: Guodong Xu <guodong.xu@linaro.org>
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May 22, 2015
Add a u32 in struct wl1271 to make fields reg_ch_conf_last and reg_ch_conf_pending 64bit aligned. Without this, on 64bit ARM, wlcore_set_pending_regdomain_ch() will fail at the point it calls set_bit(ch_bit_idx, (long*)wl->reg_ch_conf_pending); Here is the error message while doing iw wlan0 scan or connect: [ 760.644782] wlcore: WL1271_ACX_INTR_DATA [ 760.648734] Unhandled fault: alignment fault (0x96000021) at 0xffffffc01bdc1b54 [ 760.656048] Internal error: : 96000021 [#1] PREEMPT SMP [ 760.661267] Modules linked in: arc4 wl18xx wlcore mac80211 cfg80211 wlcore_sdio ti_conf_wl18xx btwilink st_drv bluetooth rfkill [ 760.672824] CPU: 0 PID: 1514 Comm: irq/198-wl18xx Tainted: G W 3.10.52-wl-00204-gf704232-dirty #8 [ 760.682558] task: ffffffc01d956040 ti: ffffffc01bea4000 task.ti: ffffffc01bea4000 [ 760.690043] PC is at set_bit+0x14/0x30 [ 760.693806] LR is at wlcore_set_pending_regdomain_ch+0x38/0x44 [wlcore] Signed-off-by: Guodong Xu <guodong.xu@linaro.org>
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Dec 10, 2015
Alex reported the following crash when using fq_codel with htb: crash> bt PID: 630839 TASK: ffff8823c990d280 CPU: 14 COMMAND: "tc" [... snip ...] #8 [ffff8820ceec17a0] page_fault at ffffffff8160a8c2 [exception RIP: htb_qlen_notify+24] RIP: ffffffffa0841718 RSP: ffff8820ceec1858 RFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff88241747b400 RDX: ffff88241747b408 RSI: 0000000000000000 RDI: ffff8811fb27d000 RBP: ffff8820ceec1868 R8: ffff88120cdeff24 R9: ffff88120cdeff30 R10: 0000000000000bd4 R11: ffffffffa0840919 R12: ffffffffa0843340 R13: 0000000000000000 R14: 0000000000000001 R15: ffff8808dae5c2e8 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #9 [...] qdisc_tree_decrease_qlen at ffffffff81565375 torvalds#10 [...] fq_codel_dequeue at ffffffffa084e0a0 [sch_fq_codel] torvalds#11 [...] fq_codel_reset at ffffffffa084e2f8 [sch_fq_codel] torvalds#12 [...] qdisc_destroy at ffffffff81560d2d torvalds#13 [...] htb_destroy_class at ffffffffa08408f8 [sch_htb] torvalds#14 [...] htb_put at ffffffffa084095c [sch_htb] torvalds#15 [...] tc_ctl_tclass at ffffffff815645a3 torvalds#16 [...] rtnetlink_rcv_msg at ffffffff81552cb0 [... snip ...] As Jamal pointed out, there is actually no need to call dequeue to purge the queued skb's in reset, data structures can be just reset explicitly. Therefore, we reset everything except config's and stats, so that we would have a fresh start after device flipping. Fixes: 4b549a2 ("fq_codel: Fair Queue Codel AQM") Reported-by: Alex Gartrell <agartrell@fb.com> Cc: Alex Gartrell <agartrell@fb.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> [xiyou.wangcong@gmail.com: added codel_vars_init() and qdisc_qstats_backlog_dec()] Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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Dec 10, 2015
It turns out that a PV domU also requires the "Xen PV" APIC driver. Otherwise, the flat driver is used and we get stuck in busy loops that never exit, such as in this stack trace: (gdb) target remote localhost:9999 Remote debugging using localhost:9999 __xapic_wait_icr_idle () at ./arch/x86/include/asm/ipi.h:56 56 while (native_apic_mem_read(APIC_ICR) & APIC_ICR_BUSY) (gdb) bt #0 __xapic_wait_icr_idle () at ./arch/x86/include/asm/ipi.h:56 #1 __default_send_IPI_shortcut (shortcut=<optimized out>, dest=<optimized out>, vector=<optimized out>) at ./arch/x86/include/asm/ipi.h:75 #2 apic_send_IPI_self (vector=246) at arch/x86/kernel/apic/probe_64.c:54 #3 0xffffffff81011336 in arch_irq_work_raise () at arch/x86/kernel/irq_work.c:47 #4 0xffffffff8114990c in irq_work_queue (work=0xffff88000fc0e400) at kernel/irq_work.c:100 #5 0xffffffff8110c29d in wake_up_klogd () at kernel/printk/printk.c:2633 #6 0xffffffff8110ca60 in vprintk_emit (facility=0, level=<optimized out>, dict=0x0 <irq_stack_union>, dictlen=<optimized out>, fmt=<optimized out>, args=<optimized out>) at kernel/printk/printk.c:1778 #7 0xffffffff816010c8 in printk (fmt=<optimized out>) at kernel/printk/printk.c:1868 #8 0xffffffffc00013ea in ?? () #9 0x0000000000000000 in ?? () Mailing-list-thread: https://lkml.org/lkml/2015/8/4/755 Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Cc: <stable@vger.kernel.org> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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commit e81107d upstream. My colleague ran into a program stall on a x86_64 server, where n_tty_read() was waiting for data even if there was data in the buffer in the pty. kernel stack for the stuck process looks like below. #0 [ffff88303d107b58] __schedule at ffffffff815c4b20 #1 [ffff88303d107bd0] schedule at ffffffff815c513e #2 [ffff88303d107bf0] schedule_timeout at ffffffff815c7818 #3 [ffff88303d107ca0] wait_woken at ffffffff81096bd2 #4 [ffff88303d107ce0] n_tty_read at ffffffff8136fa23 #5 [ffff88303d107dd0] tty_read at ffffffff81368013 #6 [ffff88303d107e20] __vfs_read at ffffffff811a3704 #7 [ffff88303d107ec0] vfs_read at ffffffff811a3a57 #8 [ffff88303d107f00] sys_read at ffffffff811a4306 #9 [ffff88303d107f50] entry_SYSCALL_64_fastpath at ffffffff815c86d7 There seems to be two problems causing this issue. First, in drivers/tty/n_tty.c, __receive_buf() stores the data and updates ldata->commit_head using smp_store_release() and then checks the wait queue using waitqueue_active(). However, since there is no memory barrier, __receive_buf() could return without calling wake_up_interactive_poll(), and at the same time, n_tty_read() could start to wait in wait_woken() as in the following chart. __receive_buf() n_tty_read() ------------------------------------------------------------------------ if (waitqueue_active(&tty->read_wait)) /* Memory operations issued after the RELEASE may be completed before the RELEASE operation has completed */ add_wait_queue(&tty->read_wait, &wait); ... if (!input_available_p(tty, 0)) { smp_store_release(&ldata->commit_head, ldata->read_head); ... timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout); ------------------------------------------------------------------------ The second problem is that n_tty_read() also lacks a memory barrier call and could also cause __receive_buf() to return without calling wake_up_interactive_poll(), and n_tty_read() to wait in wait_woken() as in the chart below. __receive_buf() n_tty_read() ------------------------------------------------------------------------ spin_lock_irqsave(&q->lock, flags); /* from add_wait_queue() */ ... if (!input_available_p(tty, 0)) { /* Memory operations issued after the RELEASE may be completed before the RELEASE operation has completed */ smp_store_release(&ldata->commit_head, ldata->read_head); if (waitqueue_active(&tty->read_wait)) __add_wait_queue(q, wait); spin_unlock_irqrestore(&q->lock,flags); /* from add_wait_queue() */ ... timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout); ------------------------------------------------------------------------ There are also other places in drivers/tty/n_tty.c which have similar calls to waitqueue_active(), so instead of adding many memory barrier calls, this patch simply removes the call to waitqueue_active(), leaving just wake_up*() behind. This fixes both problems because, even though the memory access before or after the spinlocks in both wake_up*() and add_wait_queue() can sneak into the critical section, it cannot go past it and the critical section assures that they will be serialized (please see "INTER-CPU ACQUIRING BARRIER EFFECTS" in Documentation/memory-barriers.txt for a better explanation). Moreover, the resulting code is much simpler. Latency measurement using a ping-pong test over a pty doesn't show any visible performance drop. Signed-off-by: Kosuke Tatsukawa <tatsu@ab.jp.nec.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Mar 23, 2017
[ Upstream commit 45caeaa ] As Eric Dumazet pointed out this also needs to be fixed in IPv6. v2: Contains the IPv6 tcp/Ipv6 dccp patches as well. We have seen a few incidents lately where a dst_enty has been freed with a dangling TCP socket reference (sk->sk_dst_cache) pointing to that dst_entry. If the conditions/timings are right a crash then ensues when the freed dst_entry is referenced later on. A Common crashing back trace is: #8 [] page_fault at ffffffff8163e648 [exception RIP: __tcp_ack_snd_check+74] . . #9 [] tcp_rcv_established at ffffffff81580b64 torvalds#10 [] tcp_v4_do_rcv at ffffffff8158b54a torvalds#11 [] tcp_v4_rcv at ffffffff8158cd02 torvalds#12 [] ip_local_deliver_finish at ffffffff815668f4 torvalds#13 [] ip_local_deliver at ffffffff81566bd9 torvalds#14 [] ip_rcv_finish at ffffffff8156656d torvalds#15 [] ip_rcv at ffffffff81566f06 torvalds#16 [] __netif_receive_skb_core at ffffffff8152b3a2 torvalds#17 [] __netif_receive_skb at ffffffff8152b608 torvalds#18 [] netif_receive_skb at ffffffff8152b690 torvalds#19 [] vmxnet3_rq_rx_complete at ffffffffa015eeaf [vmxnet3] torvalds#20 [] vmxnet3_poll_rx_only at ffffffffa015f32a [vmxnet3] torvalds#21 [] net_rx_action at ffffffff8152bac2 torvalds#22 [] __do_softirq at ffffffff81084b4f torvalds#23 [] call_softirq at ffffffff8164845c torvalds#24 [] do_softirq at ffffffff81016fc5 torvalds#25 [] irq_exit at ffffffff81084ee5 torvalds#26 [] do_IRQ at ffffffff81648ff8 Of course it may happen with other NIC drivers as well. It's found the freed dst_entry here: 224 static bool tcp_in_quickack_mode(struct sock *sk)↩ 225 {↩ 226 ▹ const struct inet_connection_sock *icsk = inet_csk(sk);↩ 227 ▹ const struct dst_entry *dst = __sk_dst_get(sk);↩ 228 ↩ 229 ▹ return (dst && dst_metric(dst, RTAX_QUICKACK)) ||↩ 230 ▹ ▹ (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong);↩ 231 }↩ But there are other backtraces attributed to the same freed dst_entry in netfilter code as well. All the vmcores showed 2 significant clues: - Remote hosts behind the default gateway had always been redirected to a different gateway. A rtable/dst_entry will be added for that host. Making more dst_entrys with lower reference counts. Making this more probable. - All vmcores showed a postitive LockDroppedIcmps value, e.g: LockDroppedIcmps 267 A closer look at the tcp_v4_err() handler revealed that do_redirect() will run regardless of whether user space has the socket locked. This can result in a race condition where the same dst_entry cached in sk->sk_dst_entry can be decremented twice for the same socket via: do_redirect()->__sk_dst_check()-> dst_release(). Which leads to the dst_entry being prematurely freed with another socket pointing to it via sk->sk_dst_cache and a subsequent crash. To fix this skip do_redirect() if usespace has the socket locked. Instead let the redirect take place later when user space does not have the socket locked. The dccp/IPv6 code is very similar in this respect, so fixing it there too. As Eric Garver pointed out the following commit now invalidates routes. Which can set the dst->obsolete flag so that ipv4_dst_check() returns null and triggers the dst_release(). Fixes: ceb3320 ("ipv4: Kill routes during PMTU/redirect updates.") Cc: Eric Garver <egarver@redhat.com> Cc: Hannes Sowa <hsowa@redhat.com> Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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May 26, 2017
commit a575813 upstream. Reported by syzkaller: BUG: unable to handle kernel paging request at ffffffffc07f6a2e IP: report_bug+0x94/0x120 PGD 348e12067 P4D 348e12067 PUD 348e14067 PMD 3cbd84067 PTE 80000003f7e87161 Oops: 0003 [#1] SMP CPU: 2 PID: 7091 Comm: kvm_load_guest_ Tainted: G OE 4.11.0+ #8 task: ffff92fdfb525400 task.stack: ffffbda6c3d04000 RIP: 0010:report_bug+0x94/0x120 RSP: 0018:ffffbda6c3d07b20 EFLAGS: 00010202 do_trap+0x156/0x170 do_error_trap+0xa3/0x170 ? kvm_load_guest_fpu.part.175+0x12a/0x170 [kvm] ? mark_held_locks+0x79/0xa0 ? retint_kernel+0x10/0x10 ? trace_hardirqs_off_thunk+0x1a/0x1c do_invalid_op+0x20/0x30 invalid_op+0x1e/0x30 RIP: 0010:kvm_load_guest_fpu.part.175+0x12a/0x170 [kvm] ? kvm_load_guest_fpu.part.175+0x1c/0x170 [kvm] kvm_arch_vcpu_ioctl_run+0xed6/0x1b70 [kvm] kvm_vcpu_ioctl+0x384/0x780 [kvm] ? kvm_vcpu_ioctl+0x384/0x780 [kvm] ? sched_clock+0x13/0x20 ? __do_page_fault+0x2a0/0x550 do_vfs_ioctl+0xa4/0x700 ? up_read+0x1f/0x40 ? __do_page_fault+0x2a0/0x550 SyS_ioctl+0x79/0x90 entry_SYSCALL_64_fastpath+0x23/0xc2 SDM mentioned that "The MXCSR has several reserved bits, and attempting to write a 1 to any of these bits will cause a general-protection exception(#GP) to be generated". The syzkaller forks' testcase overrides xsave area w/ random values and steps on the reserved bits of MXCSR register. The damaged MXCSR register values of guest will be restored to SSEx MXCSR register before vmentry. This patch fixes it by catching userspace override MXCSR register reserved bits w/ random values and bails out immediately. Reported-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Jul 6, 2017
INFO: task gnome-terminal-:1734 blocked for more than 120 seconds. Not tainted 4.12.0-rc4+ #8 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. gnome-terminal- D 0 1734 1015 0x00000000 Call Trace: __schedule+0x3cd/0xb30 schedule+0x40/0x90 kvm_async_pf_task_wait+0x1cc/0x270 ? __vfs_read+0x37/0x150 ? prepare_to_swait+0x22/0x70 do_async_page_fault+0x77/0xb0 ? do_async_page_fault+0x77/0xb0 async_page_fault+0x28/0x30 This is triggered by running both win7 and win2016 on L1 KVM simultaneously, and then gives stress to memory on L1, I can observed this hang on L1 when at least ~70% swap area is occupied on L0. This is due to async pf was injected to L2 which should be injected to L1, L2 guest starts receiving pagefault w/ bogus %cr2(apf token from the host actually), and L1 guest starts accumulating tasks stuck in D state in kvm_async_pf_task_wait() since missing PAGE_READY async_pfs. This patch fixes the hang by doing async pf when executing L1 guest. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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syzbot caught an infinite recursion in nsh_gso_segment(). Problem here is that we need to make sure the NSH header is of reasonable length. BUG: MAX_LOCK_DEPTH too low! turning off the locking correctness validator. depth: 48 max: 48! 48 locks held by syz-executor0/10189: #0: (ptrval) (rcu_read_lock_bh){....}, at: __dev_queue_xmit+0x30f/0x34c0 net/core/dev.c:3517 #1: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #1: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #2: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #2: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #3: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #3: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #4: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #4: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #5: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #5: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #6: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #6: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #7: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #7: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #8: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #8: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #9: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #9: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#10: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#10: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#11: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#11: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#12: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#12: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#13: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#13: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#14: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#14: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#15: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#15: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#16: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#16: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#17: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#17: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#18: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#18: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#19: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#19: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#20: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#20: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#21: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#21: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#22: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#22: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#23: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#23: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#24: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#24: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#25: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#25: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#26: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#26: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#27: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#27: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#28: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#28: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#29: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#29: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#30: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#30: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#31: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#31: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 dccp_close: ABORT with 65423 bytes unread torvalds#32: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#32: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#33: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#33: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#34: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#34: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#35: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#35: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#36: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#36: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#37: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#37: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#38: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#38: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#39: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#39: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#40: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#40: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#41: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#41: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#42: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#42: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#43: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#43: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#44: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#44: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#45: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#45: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#46: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#46: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#47: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#47: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 INFO: lockdep is turned off. CPU: 1 PID: 10189 Comm: syz-executor0 Not tainted 4.17.0-rc2+ torvalds#26 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1b9/0x294 lib/dump_stack.c:113 __lock_acquire+0x1788/0x5140 kernel/locking/lockdep.c:3449 lock_acquire+0x1dc/0x520 kernel/locking/lockdep.c:3920 rcu_lock_acquire include/linux/rcupdate.h:246 [inline] rcu_read_lock include/linux/rcupdate.h:632 [inline] skb_mac_gso_segment+0x25b/0x720 net/core/dev.c:2789 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 __skb_gso_segment+0x3bb/0x870 net/core/dev.c:2865 skb_gso_segment include/linux/netdevice.h:4025 [inline] validate_xmit_skb+0x54d/0xd90 net/core/dev.c:3118 validate_xmit_skb_list+0xbf/0x120 net/core/dev.c:3168 sch_direct_xmit+0x354/0x11e0 net/sched/sch_generic.c:312 qdisc_restart net/sched/sch_generic.c:399 [inline] __qdisc_run+0x741/0x1af0 net/sched/sch_generic.c:410 __dev_xmit_skb net/core/dev.c:3243 [inline] __dev_queue_xmit+0x28ea/0x34c0 net/core/dev.c:3551 dev_queue_xmit+0x17/0x20 net/core/dev.c:3616 packet_snd net/packet/af_packet.c:2951 [inline] packet_sendmsg+0x40f8/0x6070 net/packet/af_packet.c:2976 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:639 __sys_sendto+0x3d7/0x670 net/socket.c:1789 __do_sys_sendto net/socket.c:1801 [inline] __se_sys_sendto net/socket.c:1797 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1797 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe Fixes: c411ed8 ("nsh: add GSO support") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Jiri Benc <jbenc@redhat.com> Reported-by: syzbot <syzkaller@googlegroups.com> Acked-by: Jiri Benc <jbenc@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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[ Upstream commit af50e4b ] syzbot caught an infinite recursion in nsh_gso_segment(). Problem here is that we need to make sure the NSH header is of reasonable length. BUG: MAX_LOCK_DEPTH too low! turning off the locking correctness validator. depth: 48 max: 48! 48 locks held by syz-executor0/10189: #0: (ptrval) (rcu_read_lock_bh){....}, at: __dev_queue_xmit+0x30f/0x34c0 net/core/dev.c:3517 #1: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #1: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #2: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #2: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #3: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #3: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #4: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #4: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #5: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #5: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #6: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #6: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #7: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #7: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #8: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #8: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 #9: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] #9: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#10: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#10: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#11: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#11: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#12: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#12: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#13: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#13: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#14: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#14: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#15: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#15: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#16: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#16: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#17: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#17: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#18: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#18: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#19: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#19: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#20: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#20: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#21: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#21: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#22: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#22: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#23: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#23: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#24: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#24: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#25: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#25: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#26: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#26: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#27: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#27: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#28: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#28: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#29: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#29: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#30: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#30: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#31: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#31: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 dccp_close: ABORT with 65423 bytes unread torvalds#32: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#32: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#33: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#33: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#34: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#34: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#35: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#35: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#36: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#36: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#37: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#37: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#38: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#38: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#39: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#39: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#40: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#40: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#41: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#41: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#42: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#42: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#43: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#43: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#44: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#44: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#45: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#45: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#46: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#46: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 torvalds#47: (ptrval) (rcu_read_lock){....}, at: __skb_pull include/linux/skbuff.h:2080 [inline] torvalds#47: (ptrval) (rcu_read_lock){....}, at: skb_mac_gso_segment+0x221/0x720 net/core/dev.c:2787 INFO: lockdep is turned off. CPU: 1 PID: 10189 Comm: syz-executor0 Not tainted 4.17.0-rc2+ torvalds#26 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1b9/0x294 lib/dump_stack.c:113 __lock_acquire+0x1788/0x5140 kernel/locking/lockdep.c:3449 lock_acquire+0x1dc/0x520 kernel/locking/lockdep.c:3920 rcu_lock_acquire include/linux/rcupdate.h:246 [inline] rcu_read_lock include/linux/rcupdate.h:632 [inline] skb_mac_gso_segment+0x25b/0x720 net/core/dev.c:2789 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 nsh_gso_segment+0x405/0xb60 net/nsh/nsh.c:107 skb_mac_gso_segment+0x3ad/0x720 net/core/dev.c:2792 __skb_gso_segment+0x3bb/0x870 net/core/dev.c:2865 skb_gso_segment include/linux/netdevice.h:4025 [inline] validate_xmit_skb+0x54d/0xd90 net/core/dev.c:3118 validate_xmit_skb_list+0xbf/0x120 net/core/dev.c:3168 sch_direct_xmit+0x354/0x11e0 net/sched/sch_generic.c:312 qdisc_restart net/sched/sch_generic.c:399 [inline] __qdisc_run+0x741/0x1af0 net/sched/sch_generic.c:410 __dev_xmit_skb net/core/dev.c:3243 [inline] __dev_queue_xmit+0x28ea/0x34c0 net/core/dev.c:3551 dev_queue_xmit+0x17/0x20 net/core/dev.c:3616 packet_snd net/packet/af_packet.c:2951 [inline] packet_sendmsg+0x40f8/0x6070 net/packet/af_packet.c:2976 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:639 __sys_sendto+0x3d7/0x670 net/socket.c:1789 __do_sys_sendto net/socket.c:1801 [inline] __se_sys_sendto net/socket.c:1797 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1797 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe Fixes: c411ed8 ("nsh: add GSO support") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Jiri Benc <jbenc@redhat.com> Reported-by: syzbot <syzkaller@googlegroups.com> Acked-by: Jiri Benc <jbenc@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 8a5a916 ] While running btrfs/011, I hit the following lockdep splat. This is the important bit: pcpu_alloc+0x1ac/0x5e0 __percpu_counter_init+0x4e/0xb0 btrfs_init_fs_root+0x99/0x1c0 [btrfs] btrfs_get_fs_root.part.54+0x5b/0x150 [btrfs] resolve_indirect_refs+0x130/0x830 [btrfs] find_parent_nodes+0x69e/0xff0 [btrfs] btrfs_find_all_roots_safe+0xa0/0x110 [btrfs] btrfs_find_all_roots+0x50/0x70 [btrfs] btrfs_qgroup_prepare_account_extents+0x53/0x90 [btrfs] btrfs_commit_transaction+0x3ce/0x9b0 [btrfs] The percpu_counter_init call in btrfs_alloc_subvolume_writers uses GFP_KERNEL, which we can't do during transaction commit. This switches it to GFP_NOFS. ======================================================== WARNING: possible irq lock inversion dependency detected 4.12.14-kvmsmall #8 Tainted: G W -------------------------------------------------------- kswapd0/50 just changed the state of lock: (&delayed_node->mutex){+.+.-.}, at: [<ffffffffc06994fa>] __btrfs_release_delayed_node+0x3a/0x1f0 [btrfs] but this lock took another, RECLAIM_FS-unsafe lock in the past: (pcpu_alloc_mutex){+.+.+.} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Chain exists of: &delayed_node->mutex --> &found->groups_sem --> pcpu_alloc_mutex Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(pcpu_alloc_mutex); local_irq_disable(); lock(&delayed_node->mutex); lock(&found->groups_sem); <Interrupt> lock(&delayed_node->mutex); *** DEADLOCK *** 2 locks held by kswapd0/50: #0: (shrinker_rwsem){++++..}, at: [<ffffffff811dc11f>] shrink_slab+0x7f/0x5b0 #1: (&type->s_umount_key#30){+++++.}, at: [<ffffffff8126dec6>] trylock_super+0x16/0x50 the shortest dependencies between 2nd lock and 1st lock: -> (pcpu_alloc_mutex){+.+.+.} ops: 4904 { HARDIRQ-ON-W at: __mutex_lock+0x4e/0x8c0 pcpu_alloc+0x1ac/0x5e0 alloc_kmem_cache_cpus.isra.70+0x25/0xa0 __do_tune_cpucache+0x2c/0x220 do_tune_cpucache+0x26/0xc0 enable_cpucache+0x6d/0xf0 kmem_cache_init_late+0x42/0x75 start_kernel+0x343/0x4cb x86_64_start_kernel+0x127/0x134 secondary_startup_64+0xa5/0xb0 SOFTIRQ-ON-W at: __mutex_lock+0x4e/0x8c0 pcpu_alloc+0x1ac/0x5e0 alloc_kmem_cache_cpus.isra.70+0x25/0xa0 __do_tune_cpucache+0x2c/0x220 do_tune_cpucache+0x26/0xc0 enable_cpucache+0x6d/0xf0 kmem_cache_init_late+0x42/0x75 start_kernel+0x343/0x4cb x86_64_start_kernel+0x127/0x134 secondary_startup_64+0xa5/0xb0 RECLAIM_FS-ON-W at: __kmalloc+0x47/0x310 pcpu_extend_area_map+0x2b/0xc0 pcpu_alloc+0x3ec/0x5e0 alloc_kmem_cache_cpus.isra.70+0x25/0xa0 __do_tune_cpucache+0x2c/0x220 do_tune_cpucache+0x26/0xc0 enable_cpucache+0x6d/0xf0 __kmem_cache_create+0x1bf/0x390 create_cache+0xba/0x1b0 kmem_cache_create+0x1f8/0x2b0 ksm_init+0x6f/0x19d do_one_initcall+0x50/0x1b0 kernel_init_freeable+0x201/0x289 kernel_init+0xa/0x100 ret_from_fork+0x3a/0x50 INITIAL USE at: __mutex_lock+0x4e/0x8c0 pcpu_alloc+0x1ac/0x5e0 alloc_kmem_cache_cpus.isra.70+0x25/0xa0 setup_cpu_cache+0x2f/0x1f0 __kmem_cache_create+0x1bf/0x390 create_boot_cache+0x8b/0xb1 kmem_cache_init+0xa1/0x19e start_kernel+0x270/0x4cb x86_64_start_kernel+0x127/0x134 secondary_startup_64+0xa5/0xb0 } ... key at: [<ffffffff821d8e70>] pcpu_alloc_mutex+0x70/0xa0 ... acquired at: pcpu_alloc+0x1ac/0x5e0 __percpu_counter_init+0x4e/0xb0 btrfs_init_fs_root+0x99/0x1c0 [btrfs] btrfs_get_fs_root.part.54+0x5b/0x150 [btrfs] resolve_indirect_refs+0x130/0x830 [btrfs] find_parent_nodes+0x69e/0xff0 [btrfs] btrfs_find_all_roots_safe+0xa0/0x110 [btrfs] btrfs_find_all_roots+0x50/0x70 [btrfs] btrfs_qgroup_prepare_account_extents+0x53/0x90 [btrfs] btrfs_commit_transaction+0x3ce/0x9b0 [btrfs] transaction_kthread+0x176/0x1b0 [btrfs] kthread+0x102/0x140 ret_from_fork+0x3a/0x50 -> (&fs_info->commit_root_sem){++++..} ops: 1566382 { HARDIRQ-ON-W at: down_write+0x3e/0xa0 cache_block_group+0x287/0x420 [btrfs] find_free_extent+0x106c/0x12d0 [btrfs] btrfs_reserve_extent+0xd8/0x170 [btrfs] cow_file_range.isra.66+0x133/0x470 [btrfs] run_delalloc_range+0x121/0x410 [btrfs] writepage_delalloc.isra.50+0xfe/0x180 [btrfs] __extent_writepage+0x19a/0x360 [btrfs] extent_write_cache_pages.constprop.56+0x249/0x3e0 [btrfs] extent_writepages+0x4d/0x60 [btrfs] do_writepages+0x1a/0x70 __filemap_fdatawrite_range+0xa7/0xe0 btrfs_rename+0x5ee/0xdb0 [btrfs] vfs_rename+0x52a/0x7e0 SyS_rename+0x351/0x3b0 do_syscall_64+0x79/0x1e0 entry_SYSCALL_64_after_hwframe+0x42/0xb7 HARDIRQ-ON-R at: down_read+0x35/0x90 caching_thread+0x57/0x560 [btrfs] normal_work_helper+0x1c0/0x5e0 [btrfs] process_one_work+0x1e0/0x5c0 worker_thread+0x44/0x390 kthread+0x102/0x140 ret_from_fork+0x3a/0x50 SOFTIRQ-ON-W at: down_write+0x3e/0xa0 cache_block_group+0x287/0x420 [btrfs] find_free_extent+0x106c/0x12d0 [btrfs] btrfs_reserve_extent+0xd8/0x170 [btrfs] cow_file_range.isra.66+0x133/0x470 [btrfs] run_delalloc_range+0x121/0x410 [btrfs] writepage_delalloc.isra.50+0xfe/0x180 [btrfs] __extent_writepage+0x19a/0x360 [btrfs] extent_write_cache_pages.constprop.56+0x249/0x3e0 [btrfs] extent_writepages+0x4d/0x60 [btrfs] do_writepages+0x1a/0x70 __filemap_fdatawrite_range+0xa7/0xe0 btrfs_rename+0x5ee/0xdb0 [btrfs] vfs_rename+0x52a/0x7e0 SyS_rename+0x351/0x3b0 do_syscall_64+0x79/0x1e0 entry_SYSCALL_64_after_hwframe+0x42/0xb7 SOFTIRQ-ON-R at: down_read+0x35/0x90 caching_thread+0x57/0x560 [btrfs] normal_work_helper+0x1c0/0x5e0 [btrfs] process_one_work+0x1e0/0x5c0 worker_thread+0x44/0x390 kthread+0x102/0x140 ret_from_fork+0x3a/0x50 INITIAL USE at: down_write+0x3e/0xa0 cache_block_group+0x287/0x420 [btrfs] find_free_extent+0x106c/0x12d0 [btrfs] btrfs_reserve_extent+0xd8/0x170 [btrfs] cow_file_range.isra.66+0x133/0x470 [btrfs] run_delalloc_range+0x121/0x410 [btrfs] writepage_delalloc.isra.50+0xfe/0x180 [btrfs] __extent_writepage+0x19a/0x360 [btrfs] extent_write_cache_pages.constprop.56+0x249/0x3e0 [btrfs] extent_writepages+0x4d/0x60 [btrfs] do_writepages+0x1a/0x70 __filemap_fdatawrite_range+0xa7/0xe0 btrfs_rename+0x5ee/0xdb0 [btrfs] vfs_rename+0x52a/0x7e0 SyS_rename+0x351/0x3b0 do_syscall_64+0x79/0x1e0 entry_SYSCALL_64_after_hwframe+0x42/0xb7 } ... key at: [<ffffffffc0729578>] __key.61970+0x0/0xfffffffffff9aa88 [btrfs] ... acquired at: cache_block_group+0x287/0x420 [btrfs] find_free_extent+0x106c/0x12d0 [btrfs] btrfs_reserve_extent+0xd8/0x170 [btrfs] btrfs_alloc_tree_block+0x12f/0x4c0 [btrfs] btrfs_create_tree+0xbb/0x2a0 [btrfs] btrfs_create_uuid_tree+0x37/0x140 [btrfs] open_ctree+0x23c0/0x2660 [btrfs] btrfs_mount+0xd36/0xf90 [btrfs] mount_fs+0x3a/0x160 vfs_kern_mount+0x66/0x150 btrfs_mount+0x18c/0xf90 [btrfs] mount_fs+0x3a/0x160 vfs_kern_mount+0x66/0x150 do_mount+0x1c1/0xcc0 SyS_mount+0x7e/0xd0 do_syscall_64+0x79/0x1e0 entry_SYSCALL_64_after_hwframe+0x42/0xb7 -> (&found->groups_sem){++++..} ops: 2134587 { HARDIRQ-ON-W at: down_write+0x3e/0xa0 __link_block_group+0x34/0x130 [btrfs] btrfs_read_block_groups+0x33d/0x7b0 [btrfs] open_ctree+0x2054/0x2660 [btrfs] btrfs_mount+0xd36/0xf90 [btrfs] mount_fs+0x3a/0x160 vfs_kern_mount+0x66/0x150 btrfs_mount+0x18c/0xf90 [btrfs] mount_fs+0x3a/0x160 vfs_kern_mount+0x66/0x150 do_mount+0x1c1/0xcc0 SyS_mount+0x7e/0xd0 do_syscall_64+0x79/0x1e0 entry_SYSCALL_64_after_hwframe+0x42/0xb7 HARDIRQ-ON-R at: down_read+0x35/0x90 btrfs_calc_num_tolerated_disk_barrier_failures+0x113/0x1f0 [btrfs] open_ctree+0x207b/0x2660 [btrfs] btrfs_mount+0xd36/0xf90 [btrfs] mount_fs+0x3a/0x160 vfs_kern_mount+0x66/0x150 btrfs_mount+0x18c/0xf90 [btrfs] mount_fs+0x3a/0x160 vfs_kern_mount+0x66/0x150 do_mount+0x1c1/0xcc0 SyS_mount+0x7e/0xd0 do_syscall_64+0x79/0x1e0 entry_SYSCALL_64_after_hwframe+0x42/0xb7 SOFTIRQ-ON-W at: down_write+0x3e/0xa0 __link_block_group+0x34/0x130 [btrfs] btrfs_read_block_groups+0x33d/0x7b0 [btrfs] open_ctree+0x2054/0x2660 [btrfs] btrfs_mount+0xd36/0xf90 [btrfs] mount_fs+0x3a/0x160 vfs_kern_mount+0x66/0x150 btrfs_mount+0x18c/0xf90 [btrfs] mount_fs+0x3a/0x160 vfs_kern_mount+0x66/0x150 do_mount+0x1c1/0xcc0 SyS_mount+0x7e/0xd0 do_syscall_64+0x79/0x1e0 entry_SYSCALL_64_after_hwframe+0x42/0xb7 SOFTIRQ-ON-R at: down_read+0x35/0x90 btrfs_calc_num_tolerated_disk_barrier_failures+0x113/0x1f0 [btrfs] open_ctree+0x207b/0x2660 [btrfs] btrfs_mount+0xd36/0xf90 [btrfs] mount_fs+0x3a/0x160 vfs_kern_mount+0x66/0x150 btrfs_mount+0x18c/0xf90 [btrfs] mount_fs+0x3a/0x160 vfs_kern_mount+0x66/0x150 do_mount+0x1c1/0xcc0 SyS_mount+0x7e/0xd0 do_syscall_64+0x79/0x1e0 entry_SYSCALL_64_after_hwframe+0x42/0xb7 INITIAL USE at: down_write+0x3e/0xa0 __link_block_group+0x34/0x130 [btrfs] btrfs_read_block_groups+0x33d/0x7b0 [btrfs] open_ctree+0x2054/0x2660 [btrfs] btrfs_mount+0xd36/0xf90 [btrfs] mount_fs+0x3a/0x160 vfs_kern_mount+0x66/0x150 btrfs_mount+0x18c/0xf90 [btrfs] mount_fs+0x3a/0x160 vfs_kern_mount+0x66/0x150 do_mount+0x1c1/0xcc0 SyS_mount+0x7e/0xd0 do_syscall_64+0x79/0x1e0 entry_SYSCALL_64_after_hwframe+0x42/0xb7 } ... key at: [<ffffffffc0729488>] __key.59101+0x0/0xfffffffffff9ab78 [btrfs] ... acquired at: find_free_extent+0xcb4/0x12d0 [btrfs] btrfs_reserve_extent+0xd8/0x170 [btrfs] btrfs_alloc_tree_block+0x12f/0x4c0 [btrfs] __btrfs_cow_block+0x110/0x5b0 [btrfs] btrfs_cow_block+0xd7/0x290 [btrfs] btrfs_search_slot+0x1f6/0x960 [btrfs] btrfs_lookup_inode+0x2a/0x90 [btrfs] __btrfs_update_delayed_inode+0x65/0x210 [btrfs] btrfs_commit_inode_delayed_inode+0x121/0x130 [btrfs] btrfs_evict_inode+0x3fe/0x6a0 [btrfs] evict+0xc4/0x190 __dentry_kill+0xbf/0x170 dput+0x2ae/0x2f0 SyS_rename+0x2a6/0x3b0 do_syscall_64+0x79/0x1e0 entry_SYSCALL_64_after_hwframe+0x42/0xb7 -> (&delayed_node->mutex){+.+.-.} ops: 5580204 { HARDIRQ-ON-W at: __mutex_lock+0x4e/0x8c0 btrfs_delayed_update_inode+0x46/0x6e0 [btrfs] btrfs_update_inode+0x83/0x110 [btrfs] btrfs_dirty_inode+0x62/0xe0 [btrfs] touch_atime+0x8c/0xb0 do_generic_file_read+0x818/0xb10 __vfs_read+0xdc/0x150 vfs_read+0x8a/0x130 SyS_read+0x45/0xa0 do_syscall_64+0x79/0x1e0 entry_SYSCALL_64_after_hwframe+0x42/0xb7 SOFTIRQ-ON-W at: __mutex_lock+0x4e/0x8c0 btrfs_delayed_update_inode+0x46/0x6e0 [btrfs] btrfs_update_inode+0x83/0x110 [btrfs] btrfs_dirty_inode+0x62/0xe0 [btrfs] touch_atime+0x8c/0xb0 do_generic_file_read+0x818/0xb10 __vfs_read+0xdc/0x150 vfs_read+0x8a/0x130 SyS_read+0x45/0xa0 do_syscall_64+0x79/0x1e0 entry_SYSCALL_64_after_hwframe+0x42/0xb7 IN-RECLAIM_FS-W at: __mutex_lock+0x4e/0x8c0 __btrfs_release_delayed_node+0x3a/0x1f0 [btrfs] btrfs_evict_inode+0x22c/0x6a0 [btrfs] evict+0xc4/0x190 dispose_list+0x35/0x50 prune_icache_sb+0x42/0x50 super_cache_scan+0x139/0x190 shrink_slab+0x262/0x5b0 shrink_node+0x2eb/0x2f0 kswapd+0x2eb/0x890 kthread+0x102/0x140 ret_from_fork+0x3a/0x50 INITIAL USE at: __mutex_lock+0x4e/0x8c0 btrfs_delayed_update_inode+0x46/0x6e0 [btrfs] btrfs_update_inode+0x83/0x110 [btrfs] btrfs_dirty_inode+0x62/0xe0 [btrfs] touch_atime+0x8c/0xb0 do_generic_file_read+0x818/0xb10 __vfs_read+0xdc/0x150 vfs_read+0x8a/0x130 SyS_read+0x45/0xa0 do_syscall_64+0x79/0x1e0 entry_SYSCALL_64_after_hwframe+0x42/0xb7 } ... key at: [<ffffffffc072d488>] __key.56935+0x0/0xfffffffffff96b78 [btrfs] ... acquired at: __lock_acquire+0x264/0x11c0 lock_acquire+0xbd/0x1e0 __mutex_lock+0x4e/0x8c0 __btrfs_release_delayed_node+0x3a/0x1f0 [btrfs] btrfs_evict_inode+0x22c/0x6a0 [btrfs] evict+0xc4/0x190 dispose_list+0x35/0x50 prune_icache_sb+0x42/0x50 super_cache_scan+0x139/0x190 shrink_slab+0x262/0x5b0 shrink_node+0x2eb/0x2f0 kswapd+0x2eb/0x890 kthread+0x102/0x140 ret_from_fork+0x3a/0x50 stack backtrace: CPU: 1 PID: 50 Comm: kswapd0 Tainted: G W 4.12.14-kvmsmall #8 SLE15 (unreleased) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014 Call Trace: dump_stack+0x78/0xb7 print_irq_inversion_bug.part.38+0x19f/0x1aa check_usage_forwards+0x102/0x120 ? ret_from_fork+0x3a/0x50 ? check_usage_backwards+0x110/0x110 mark_lock+0x16c/0x270 __lock_acquire+0x264/0x11c0 ? pagevec_lookup_entries+0x1a/0x30 ? truncate_inode_pages_range+0x2b3/0x7f0 lock_acquire+0xbd/0x1e0 ? __btrfs_release_delayed_node+0x3a/0x1f0 [btrfs] __mutex_lock+0x4e/0x8c0 ? __btrfs_release_delayed_node+0x3a/0x1f0 [btrfs] ? __btrfs_release_delayed_node+0x3a/0x1f0 [btrfs] ? btrfs_evict_inode+0x1f6/0x6a0 [btrfs] __btrfs_release_delayed_node+0x3a/0x1f0 [btrfs] btrfs_evict_inode+0x22c/0x6a0 [btrfs] evict+0xc4/0x190 dispose_list+0x35/0x50 prune_icache_sb+0x42/0x50 super_cache_scan+0x139/0x190 shrink_slab+0x262/0x5b0 shrink_node+0x2eb/0x2f0 kswapd+0x2eb/0x890 kthread+0x102/0x140 ? mem_cgroup_shrink_node+0x2c0/0x2c0 ? kthread_create_on_node+0x40/0x40 ret_from_fork+0x3a/0x50 Signed-off-by: Jeff Mahoney <jeffm@suse.com> Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit fca3234 ] Executing command 'perf stat -T -- ls' dumps core on x86 and s390. Here is the call back chain (done on x86): # gdb ./perf .... (gdb) r stat -T -- ls ... Program received signal SIGSEGV, Segmentation fault. 0x00007ffff56d1963 in vasprintf () from /lib64/libc.so.6 (gdb) where #0 0x00007ffff56d1963 in vasprintf () from /lib64/libc.so.6 #1 0x00007ffff56ae484 in asprintf () from /lib64/libc.so.6 #2 0x00000000004f1982 in __parse_events_add_pmu (parse_state=0x7fffffffd580, list=0xbfb970, name=0xbf3ef0 "cpu", head_config=0xbfb930, auto_merge_stats=false) at util/parse-events.c:1233 #3 0x00000000004f1c8e in parse_events_add_pmu (parse_state=0x7fffffffd580, list=0xbfb970, name=0xbf3ef0 "cpu", head_config=0xbfb930) at util/parse-events.c:1288 #4 0x0000000000537ce3 in parse_events_parse (_parse_state=0x7fffffffd580, scanner=0xbf4210) at util/parse-events.y:234 #5 0x00000000004f2c7a in parse_events__scanner (str=0x6b66c0 "task-clock,{instructions,cycles,cpu/cycles-t/,cpu/tx-start/}", parse_state=0x7fffffffd580, start_token=258) at util/parse-events.c:1673 #6 0x00000000004f2e23 in parse_events (evlist=0xbe9990, str=0x6b66c0 "task-clock,{instructions,cycles,cpu/cycles-t/,cpu/tx-start/}", err=0x0) at util/parse-events.c:1713 #7 0x000000000044e137 in add_default_attributes () at builtin-stat.c:2281 #8 0x000000000044f7b5 in cmd_stat (argc=1, argv=0x7fffffffe3b0) at builtin-stat.c:2828 #9 0x00000000004c8b0f in run_builtin (p=0xab01a0 <commands+288>, argc=4, argv=0x7fffffffe3b0) at perf.c:297 torvalds#10 0x00000000004c8d7c in handle_internal_command (argc=4, argv=0x7fffffffe3b0) at perf.c:349 torvalds#11 0x00000000004c8ece in run_argv (argcp=0x7fffffffe20c, argv=0x7fffffffe200) at perf.c:393 torvalds#12 0x00000000004c929c in main (argc=4, argv=0x7fffffffe3b0) at perf.c:537 (gdb) It turns out that a NULL pointer is referenced. Here are the function calls: ... cmd_stat() +---> add_default_attributes() +---> parse_events(evsel_list, transaction_attrs, NULL); 3rd parameter set to NULL Function parse_events(xx, xx, struct parse_events_error *err) dives into a bison generated scanner and creates parser state information for it first: struct parse_events_state parse_state = { .list = LIST_HEAD_INIT(parse_state.list), .idx = evlist->nr_entries, .error = err, <--- NULL POINTER !!! .evlist = evlist, }; Now various functions inside the bison scanner are called to end up in __parse_events_add_pmu(struct parse_events_state *parse_state, ..) with first parameter being a pointer to above structure definition. Now the PMU event name is not found (because being executed in a VM) and this function tries to create an error message with asprintf(&parse_state->error.str, ....) which references a NULL pointer and dumps core. Fix this by providing a pointer to the necessary error information instead of NULL. Technically only the else part is needed to avoid the core dump, just lets be safe... Signed-off-by: Thomas Richter <tmricht@linux.vnet.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Link: http://lkml.kernel.org/r/20180308145735.64717-1-tmricht@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 2bbea6e ] when mounting an ISO filesystem sometimes (very rarely) the system hangs because of a race condition between two tasks. PID: 6766 TASK: ffff88007b2a6dd0 CPU: 0 COMMAND: "mount" #0 [ffff880078447ae0] __schedule at ffffffff8168d605 #1 [ffff880078447b48] schedule_preempt_disabled at ffffffff8168ed49 #2 [ffff880078447b58] __mutex_lock_slowpath at ffffffff8168c995 #3 [ffff880078447bb8] mutex_lock at ffffffff8168bdef #4 [ffff880078447bd0] sr_block_ioctl at ffffffffa00b6818 [sr_mod] #5 [ffff880078447c10] blkdev_ioctl at ffffffff812fea50 #6 [ffff880078447c70] ioctl_by_bdev at ffffffff8123a8b3 #7 [ffff880078447c90] isofs_fill_super at ffffffffa04fb1e1 [isofs] #8 [ffff880078447da8] mount_bdev at ffffffff81202570 #9 [ffff880078447e18] isofs_mount at ffffffffa04f9828 [isofs] torvalds#10 [ffff880078447e28] mount_fs at ffffffff81202d09 torvalds#11 [ffff880078447e70] vfs_kern_mount at ffffffff8121ea8f torvalds#12 [ffff880078447ea8] do_mount at ffffffff81220fee torvalds#13 [ffff880078447f28] sys_mount at ffffffff812218d6 torvalds#14 [ffff880078447f80] system_call_fastpath at ffffffff81698c49 RIP: 00007fd9ea914e9a RSP: 00007ffd5d9bf648 RFLAGS: 00010246 RAX: 00000000000000a5 RBX: ffffffff81698c49 RCX: 0000000000000010 RDX: 00007fd9ec2bc210 RSI: 00007fd9ec2bc290 RDI: 00007fd9ec2bcf30 RBP: 0000000000000000 R8: 0000000000000000 R9: 0000000000000010 R10: 00000000c0ed0001 R11: 0000000000000206 R12: 00007fd9ec2bc040 R13: 00007fd9eb6b2380 R14: 00007fd9ec2bc210 R15: 00007fd9ec2bcf30 ORIG_RAX: 00000000000000a5 CS: 0033 SS: 002b This task was trying to mount the cdrom. It allocated and configured a super_block struct and owned the write-lock for the super_block->s_umount rwsem. While exclusively owning the s_umount lock, it called sr_block_ioctl and waited to acquire the global sr_mutex lock. PID: 6785 TASK: ffff880078720fb0 CPU: 0 COMMAND: "systemd-udevd" #0 [ffff880078417898] __schedule at ffffffff8168d605 #1 [ffff880078417900] schedule at ffffffff8168dc59 #2 [ffff880078417910] rwsem_down_read_failed at ffffffff8168f605 #3 [ffff880078417980] call_rwsem_down_read_failed at ffffffff81328838 #4 [ffff8800784179d0] down_read at ffffffff8168cde0 #5 [ffff8800784179e8] get_super at ffffffff81201cc7 #6 [ffff880078417a10] __invalidate_device at ffffffff8123a8de #7 [ffff880078417a40] flush_disk at ffffffff8123a94b #8 [ffff880078417a88] check_disk_change at ffffffff8123ab50 #9 [ffff880078417ab0] cdrom_open at ffffffffa00a29e1 [cdrom] torvalds#10 [ffff880078417b68] sr_block_open at ffffffffa00b6f9b [sr_mod] torvalds#11 [ffff880078417b98] __blkdev_get at ffffffff8123ba86 torvalds#12 [ffff880078417bf0] blkdev_get at ffffffff8123bd65 torvalds#13 [ffff880078417c78] blkdev_open at ffffffff8123bf9b torvalds#14 [ffff880078417c90] do_dentry_open at ffffffff811fc7f7 torvalds#15 [ffff880078417cd8] vfs_open at ffffffff811fc9cf torvalds#16 [ffff880078417d00] do_last at ffffffff8120d53d torvalds#17 [ffff880078417db0] path_openat at ffffffff8120e6b2 torvalds#18 [ffff880078417e48] do_filp_open at ffffffff8121082b torvalds#19 [ffff880078417f18] do_sys_open at ffffffff811fdd33 torvalds#20 [ffff880078417f70] sys_open at ffffffff811fde4e torvalds#21 [ffff880078417f80] system_call_fastpath at ffffffff81698c49 RIP: 00007f29438b0c20 RSP: 00007ffc76624b78 RFLAGS: 00010246 RAX: 0000000000000002 RBX: ffffffff81698c49 RCX: 0000000000000000 RDX: 00007f2944a5fa70 RSI: 00000000000a0800 RDI: 00007f2944a5fa70 RBP: 00007f2944a5f540 R8: 0000000000000000 R9: 0000000000000020 R10: 00007f2943614c40 R11: 0000000000000246 R12: ffffffff811fde4e R13: ffff880078417f78 R14: 000000000000000c R15: 00007f2944a4b010 ORIG_RAX: 0000000000000002 CS: 0033 SS: 002b This task tried to open the cdrom device, the sr_block_open function acquired the global sr_mutex lock. The call to check_disk_change() then saw an event flag indicating a possible media change and tried to flush any cached data for the device. As part of the flush, it tried to acquire the super_block->s_umount lock associated with the cdrom device. This was the same super_block as created and locked by the previous task. The first task acquires the s_umount lock and then the sr_mutex_lock; the second task acquires the sr_mutex_lock and then the s_umount lock. This patch fixes the issue by moving check_disk_change() out of cdrom_open() and let the caller take care of it. Signed-off-by: Maurizio Lombardi <mlombard@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 1105a2f upstream. In our armv8a server(QDF2400), I noticed lots of WARN_ON caused by PAGE_SIZE unaligned for rmap_item->address under memory pressure tests(start 20 guests and run memhog in the host). WARNING: CPU: 4 PID: 4641 at virt/kvm/arm/mmu.c:1826 kvm_age_hva_handler+0xc0/0xc8 CPU: 4 PID: 4641 Comm: memhog Tainted: G W 4.17.0-rc3+ #8 Call trace: kvm_age_hva_handler+0xc0/0xc8 handle_hva_to_gpa+0xa8/0xe0 kvm_age_hva+0x4c/0xe8 kvm_mmu_notifier_clear_flush_young+0x54/0x98 __mmu_notifier_clear_flush_young+0x6c/0xa0 page_referenced_one+0x154/0x1d8 rmap_walk_ksm+0x12c/0x1d0 rmap_walk+0x94/0xa0 page_referenced+0x194/0x1b0 shrink_page_list+0x674/0xc28 shrink_inactive_list+0x26c/0x5b8 shrink_node_memcg+0x35c/0x620 shrink_node+0x100/0x430 do_try_to_free_pages+0xe0/0x3a8 try_to_free_pages+0xe4/0x230 __alloc_pages_nodemask+0x564/0xdc0 alloc_pages_vma+0x90/0x228 do_anonymous_page+0xc8/0x4d0 __handle_mm_fault+0x4a0/0x508 handle_mm_fault+0xf8/0x1b0 do_page_fault+0x218/0x4b8 do_translation_fault+0x90/0xa0 do_mem_abort+0x68/0xf0 el0_da+0x24/0x28 In rmap_walk_ksm, the rmap_item->address might still have the STABLE_FLAG, then the start and end in handle_hva_to_gpa might not be PAGE_SIZE aligned. Thus it will cause exceptions in handle_hva_to_gpa on arm64. This patch fixes it by ignoring (not removing) the low bits of address when doing rmap_walk_ksm. IMO, it should be backported to stable tree. the storm of WARN_ONs is very easy for me to reproduce. More than that, I watched a panic (not reproducible) as follows: page:ffff7fe003742d80 count:-4871 mapcount:-2126053375 mapping: (null) index:0x0 flags: 0x1fffc00000000000() raw: 1fffc00000000000 0000000000000000 0000000000000000 ffffecf981470000 raw: dead000000000100 dead000000000200 ffff8017c001c000 0000000000000000 page dumped because: nonzero _refcount CPU: 29 PID: 18323 Comm: qemu-kvm Tainted: G W 4.14.15-5.hxt.aarch64 #1 Hardware name: <snip for confidential issues> Call trace: dump_backtrace+0x0/0x22c show_stack+0x24/0x2c dump_stack+0x8c/0xb0 bad_page+0xf4/0x154 free_pages_check_bad+0x90/0x9c free_pcppages_bulk+0x464/0x518 free_hot_cold_page+0x22c/0x300 __put_page+0x54/0x60 unmap_stage2_range+0x170/0x2b4 kvm_unmap_hva_handler+0x30/0x40 handle_hva_to_gpa+0xb0/0xec kvm_unmap_hva_range+0x5c/0xd0 I even injected a fault on purpose in kvm_unmap_hva_range by seting size=size-0x200, the call trace is similar as above. So I thought the panic is similarly caused by the root cause of WARN_ON. Andrea said: : It looks a straightforward safe fix, on x86 hva_to_gfn_memslot would : zap those bits and hide the misalignment caused by the low metadata : bits being erroneously left set in the address, but the arm code : notices when that's the last page in the memslot and the hva_end is : getting aligned and the size is below one page. : : I think the problem triggers in the addr += PAGE_SIZE of : unmap_stage2_ptes that never matches end because end is aligned but : addr is not. : : } while (pte++, addr += PAGE_SIZE, addr != end); : : x86 again only works on hva_start/hva_end after converting it to : gfn_start/end and that being in pfn units the bits are zapped before : they risk to cause trouble. Jia He said: : I've tested by myself in arm64 server (QDF2400,46 cpus,96G mem) Without : this patch, the WARN_ON is very easy for reproducing. After this patch, I : have run the same benchmarch for a whole day without any WARN_ONs Link: http://lkml.kernel.org/r/1525403506-6750-1-git-send-email-hejianet@gmail.com Signed-off-by: Jia He <jia.he@hxt-semitech.com> Reviewed-by: Andrea Arcangeli <aarcange@redhat.com> Tested-by: Jia He <hejianet@gmail.com> Cc: Suzuki K Poulose <Suzuki.Poulose@arm.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com> Cc: Arvind Yadav <arvind.yadav.cs@gmail.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 33a1a7b ] The issue is found by a fuzzing test. If tty_find_polling_driver() recevies an incorrect input such as ',,' or '0b', the len becomes 0 and strncmp() always return 0. In this case, a null p->ops->poll_init() is called and it causes a kernel panic. Fix this by checking name length against zero in tty_find_polling_driver(). $echo ,, > /sys/module/kgdboc/parameters/kgdboc [ 20.804451] WARNING: CPU: 1 PID: 104 at drivers/tty/serial/serial_core.c:457 uart_get_baud_rate+0xe8/0x190 [ 20.804917] Modules linked in: [ 20.805317] CPU: 1 PID: 104 Comm: sh Not tainted 4.19.0-rc7ajb #8 [ 20.805469] Hardware name: linux,dummy-virt (DT) [ 20.805732] pstate: 20000005 (nzCv daif -PAN -UAO) [ 20.805895] pc : uart_get_baud_rate+0xe8/0x190 [ 20.806042] lr : uart_get_baud_rate+0xc0/0x190 [ 20.806476] sp : ffffffc06acff940 [ 20.806676] x29: ffffffc06acff940 x28: 0000000000002580 [ 20.806977] x27: 0000000000009600 x26: 0000000000009600 [ 20.807231] x25: ffffffc06acffad0 x24: 00000000ffffeff0 [ 20.807576] x23: 0000000000000001 x22: 0000000000000000 [ 20.807807] x21: 0000000000000001 x20: 0000000000000000 [ 20.808049] x19: ffffffc06acffac8 x18: 0000000000000000 [ 20.808277] x17: 0000000000000000 x16: 0000000000000000 [ 20.808520] x15: ffffffffffffffff x14: ffffffff00000000 [ 20.808757] x13: ffffffffffffffff x12: 0000000000000001 [ 20.809011] x11: 0101010101010101 x10: ffffff880d59ff5f [ 20.809292] x9 : ffffff880d59ff5e x8 : ffffffc06acffaf3 [ 20.809549] x7 : 0000000000000000 x6 : ffffff880d59ff5f [ 20.809803] x5 : 0000000080008001 x4 : 0000000000000003 [ 20.810056] x3 : ffffff900853e6b4 x2 : dfffff9000000000 [ 20.810693] x1 : ffffffc06acffad0 x0 : 0000000000000cb0 [ 20.811005] Call trace: [ 20.811214] uart_get_baud_rate+0xe8/0x190 [ 20.811479] serial8250_do_set_termios+0xe0/0x6f4 [ 20.811719] serial8250_set_termios+0x48/0x54 [ 20.811928] uart_set_options+0x138/0x1bc [ 20.812129] uart_poll_init+0x114/0x16c [ 20.812330] tty_find_polling_driver+0x158/0x200 [ 20.812545] configure_kgdboc+0xbc/0x1bc [ 20.812745] param_set_kgdboc_var+0xb8/0x150 [ 20.812960] param_attr_store+0xbc/0x150 [ 20.813160] module_attr_store+0x40/0x58 [ 20.813364] sysfs_kf_write+0x8c/0xa8 [ 20.813563] kernfs_fop_write+0x154/0x290 [ 20.813764] vfs_write+0xf0/0x278 [ 20.813951] __arm64_sys_write+0x84/0xf4 [ 20.814400] el0_svc_common+0xf4/0x1dc [ 20.814616] el0_svc_handler+0x98/0xbc [ 20.814804] el0_svc+0x8/0xc [ 20.822005] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 [ 20.826913] Mem abort info: [ 20.827103] ESR = 0x84000006 [ 20.827352] Exception class = IABT (current EL), IL = 16 bits [ 20.827655] SET = 0, FnV = 0 [ 20.827855] EA = 0, S1PTW = 0 [ 20.828135] user pgtable: 4k pages, 39-bit VAs, pgdp = (____ptrval____) [ 20.828484] [0000000000000000] pgd=00000000aadee003, pud=00000000aadee003, pmd=0000000000000000 [ 20.829195] Internal error: Oops: 84000006 [#1] SMP [ 20.829564] Modules linked in: [ 20.829890] CPU: 1 PID: 104 Comm: sh Tainted: G W 4.19.0-rc7ajb #8 [ 20.830545] Hardware name: linux,dummy-virt (DT) [ 20.830829] pstate: 60000085 (nZCv daIf -PAN -UAO) [ 20.831174] pc : (null) [ 20.831457] lr : serial8250_do_set_termios+0x358/0x6f4 [ 20.831727] sp : ffffffc06acff9b0 [ 20.831936] x29: ffffffc06acff9b0 x28: ffffff9008d7c000 [ 20.832267] x27: ffffff900969e16f x26: 0000000000000000 [ 20.832589] x25: ffffff900969dfb0 x24: 0000000000000000 [ 20.832906] x23: ffffffc06acffad0 x22: ffffff900969e160 [ 20.833232] x21: 0000000000000000 x20: ffffffc06acffac8 [ 20.833559] x19: ffffff900969df90 x18: 0000000000000000 [ 20.833878] x17: 0000000000000000 x16: 0000000000000000 [ 20.834491] x15: ffffffffffffffff x14: ffffffff00000000 [ 20.834821] x13: ffffffffffffffff x12: 0000000000000001 [ 20.835143] x11: 0101010101010101 x10: ffffff880d59ff5f [ 20.835467] x9 : ffffff880d59ff5e x8 : ffffffc06acffaf3 [ 20.835790] x7 : 0000000000000000 x6 : ffffff880d59ff5f [ 20.836111] x5 : c06419717c314100 x4 : 0000000000000007 [ 20.836419] x3 : 0000000000000000 x2 : 0000000000000000 [ 20.836732] x1 : 0000000000000001 x0 : ffffff900969df90 [ 20.837100] Process sh (pid: 104, stack limit = 0x(____ptrval____)) [ 20.837396] Call trace: [ 20.837566] (null) [ 20.837816] serial8250_set_termios+0x48/0x54 [ 20.838089] uart_set_options+0x138/0x1bc [ 20.838570] uart_poll_init+0x114/0x16c [ 20.838834] tty_find_polling_driver+0x158/0x200 [ 20.839119] configure_kgdboc+0xbc/0x1bc [ 20.839380] param_set_kgdboc_var+0xb8/0x150 [ 20.839658] param_attr_store+0xbc/0x150 [ 20.839920] module_attr_store+0x40/0x58 [ 20.840183] sysfs_kf_write+0x8c/0xa8 [ 20.840183] sysfs_kf_write+0x8c/0xa8 [ 20.840440] kernfs_fop_write+0x154/0x290 [ 20.840702] vfs_write+0xf0/0x278 [ 20.840942] __arm64_sys_write+0x84/0xf4 [ 20.841209] el0_svc_common+0xf4/0x1dc [ 20.841471] el0_svc_handler+0x98/0xbc [ 20.841713] el0_svc+0x8/0xc [ 20.842057] Code: bad PC value [ 20.842764] ---[ end trace a8835d7de79aaadf ]--- [ 20.843134] Kernel panic - not syncing: Fatal exception [ 20.843515] SMP: stopping secondary CPUs [ 20.844289] Kernel Offset: disabled [ 20.844634] CPU features: 0x0,21806002 [ 20.844857] Memory Limit: none [ 20.845172] ---[ end Kernel panic - not syncing: Fatal exception ]--- Signed-off-by: Miles Chen <miles.chen@mediatek.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit fcd5e74 upstream. When running generic/475, we may get the following warning in dmesg: [ 6902.102154] WARNING: CPU: 3 PID: 18013 at fs/btrfs/extent-tree.c:9776 btrfs_free_block_groups+0x2af/0x3b0 [btrfs] [ 6902.109160] CPU: 3 PID: 18013 Comm: umount Tainted: G W O 4.19.0-rc8+ #8 [ 6902.110971] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 [ 6902.112857] RIP: 0010:btrfs_free_block_groups+0x2af/0x3b0 [btrfs] [ 6902.118921] RSP: 0018:ffffc9000459bdb0 EFLAGS: 00010286 [ 6902.120315] RAX: ffff880175050bb0 RBX: ffff8801124a8000 RCX: 0000000000170007 [ 6902.121969] RDX: 0000000000000002 RSI: 0000000000170007 RDI: ffffffff8125fb74 [ 6902.123716] RBP: ffff880175055d10 R08: 0000000000000000 R09: 0000000000000000 [ 6902.125417] R10: 0000000000000000 R11: 0000000000000000 R12: ffff880175055d88 [ 6902.127129] R13: ffff880175050bb0 R14: 0000000000000000 R15: dead000000000100 [ 6902.129060] FS: 00007f4507223780(0000) GS:ffff88017ba00000(0000) knlGS:0000000000000000 [ 6902.130996] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 6902.132558] CR2: 00005623599cac78 CR3: 000000014b700001 CR4: 00000000003606e0 [ 6902.134270] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 6902.135981] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 6902.137836] Call Trace: [ 6902.138939] close_ctree+0x171/0x330 [btrfs] [ 6902.140181] ? kthread_stop+0x146/0x1f0 [ 6902.141277] generic_shutdown_super+0x6c/0x100 [ 6902.142517] kill_anon_super+0x14/0x30 [ 6902.143554] btrfs_kill_super+0x13/0x100 [btrfs] [ 6902.144790] deactivate_locked_super+0x2f/0x70 [ 6902.146014] cleanup_mnt+0x3b/0x70 [ 6902.147020] task_work_run+0x9e/0xd0 [ 6902.148036] do_syscall_64+0x470/0x600 [ 6902.149142] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 6902.150375] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 6902.151640] RIP: 0033:0x7f45077a6a7b [ 6902.157324] RSP: 002b:00007ffd589f3e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 [ 6902.159187] RAX: 0000000000000000 RBX: 000055e8eec732b0 RCX: 00007f45077a6a7b [ 6902.160834] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 000055e8eec73490 [ 6902.162526] RBP: 0000000000000000 R08: 000055e8eec734b0 R09: 00007ffd589f26c0 [ 6902.164141] R10: 0000000000000000 R11: 0000000000000246 R12: 000055e8eec73490 [ 6902.165815] R13: 00007f4507ac61a4 R14: 0000000000000000 R15: 00007ffd589f40d8 [ 6902.167553] irq event stamp: 0 [ 6902.168998] hardirqs last enabled at (0): [<0000000000000000>] (null) [ 6902.170731] hardirqs last disabled at (0): [<ffffffff810cd810>] copy_process.part.55+0x3b0/0x1f00 [ 6902.172773] softirqs last enabled at (0): [<ffffffff810cd810>] copy_process.part.55+0x3b0/0x1f00 [ 6902.174671] softirqs last disabled at (0): [<0000000000000000>] (null) [ 6902.176407] ---[ end trace 463138c2986b275c ]--- [ 6902.177636] BTRFS info (device dm-3): space_info 4 has 273465344 free, is not full [ 6902.179453] BTRFS info (device dm-3): space_info total=276824064, used=4685824, pinned=18446744073708158976, reserved=0, may_use=0, readonly=65536 In the above line there's "pinned=18446744073708158976" which is an unsigned u64 value of -1392640, an obvious underflow. When transaction_kthread is running cleanup_transaction(), another fsstress is running btrfs_commit_transaction(). The btrfs_finish_extent_commit() may get the same range as btrfs_destroy_pinned_extent() got, which causes the pinned underflow. Fixes: d4b450c ("Btrfs: fix race between transaction commit and empty block group removal") CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit c7b6804 ] Building a combined ARMv4+XScale kernel produces these and other build failures: /tmp/copypage-xscale-3aa821.s: Assembler messages: /tmp/copypage-xscale-3aa821.s:167: Error: selected processor does not support `pld [r7,#0]' in ARM mode /tmp/copypage-xscale-3aa821.s:168: Error: selected processor does not support `pld [r7,torvalds#32]' in ARM mode /tmp/copypage-xscale-3aa821.s:169: Error: selected processor does not support `pld [r1,#0]' in ARM mode /tmp/copypage-xscale-3aa821.s:170: Error: selected processor does not support `pld [r1,torvalds#32]' in ARM mode /tmp/copypage-xscale-3aa821.s:171: Error: selected processor does not support `pld [r7,torvalds#64]' in ARM mode /tmp/copypage-xscale-3aa821.s:176: Error: selected processor does not support `ldrd r4,r5,[r7],#8' in ARM mode /tmp/copypage-xscale-3aa821.s:180: Error: selected processor does not support `strd r4,r5,[r1],#8' in ARM mode Add an explict .arch armv5 in the inline assembly to allow the ARMv5 specific instructions regardless of the compiler -march= target. Link: https://lore.kernel.org/r/20190809163334.489360-5-arnd@arndb.de Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit b0f3b87 ] https://bugzilla.kernel.org/show_bug.cgi?id=208565 PID: 257 TASK: ecdd0000 CPU: 0 COMMAND: "init" #0 [<c0b420ec>] (__schedule) from [<c0b423c8>] #1 [<c0b423c8>] (schedule) from [<c0b459d4>] #2 [<c0b459d4>] (rwsem_down_read_failed) from [<c0b44fa0>] #3 [<c0b44fa0>] (down_read) from [<c044233c>] #4 [<c044233c>] (f2fs_truncate_blocks) from [<c0442890>] #5 [<c0442890>] (f2fs_truncate) from [<c044d408>] #6 [<c044d408>] (f2fs_evict_inode) from [<c030be18>] #7 [<c030be18>] (evict) from [<c030a558>] #8 [<c030a558>] (iput) from [<c047c600>] #9 [<c047c600>] (f2fs_sync_node_pages) from [<c0465414>] torvalds#10 [<c0465414>] (f2fs_write_checkpoint) from [<c04575f4>] torvalds#11 [<c04575f4>] (f2fs_sync_fs) from [<c0441918>] torvalds#12 [<c0441918>] (f2fs_do_sync_file) from [<c0441098>] torvalds#13 [<c0441098>] (f2fs_sync_file) from [<c0323fa0>] torvalds#14 [<c0323fa0>] (vfs_fsync_range) from [<c0324294>] torvalds#15 [<c0324294>] (do_fsync) from [<c0324014>] torvalds#16 [<c0324014>] (sys_fsync) from [<c0108bc0>] This can be caused by flush_dirty_inode() in f2fs_sync_node_pages() where iput() requires f2fs_lock_op() again resulting in livelock. Reported-by: Zhiguo Niu <Zhiguo.Niu@unisoc.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 7ad92f6 ] This patch addresses an irq free warning and null pointer dereference error problem when nvme devices got timeout error during initialization. This problem happens when nvme_timeout() function is called while nvme_reset_work() is still in execution. This patch fixed the problem by setting flag of the problematic request to NVME_REQ_CANCELLED before calling nvme_dev_disable() to make sure __nvme_submit_sync_cmd() returns an error code and let nvme_submit_sync_cmd() fail gracefully. The following is console output. [ 62.472097] nvme nvme0: I/O 13 QID 0 timeout, disable controller [ 62.488796] nvme nvme0: could not set timestamp (881) [ 62.494888] ------------[ cut here ]------------ [ 62.495142] Trying to free already-free IRQ 11 [ 62.495366] WARNING: CPU: 0 PID: 7 at kernel/irq/manage.c:1751 free_irq+0x1f7/0x370 [ 62.495742] Modules linked in: [ 62.495902] CPU: 0 PID: 7 Comm: kworker/u4:0 Not tainted 5.8.0+ #8 [ 62.496206] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-48-gd9c812dda519-p4 [ 62.496772] Workqueue: nvme-reset-wq nvme_reset_work [ 62.497019] RIP: 0010:free_irq+0x1f7/0x370 [ 62.497223] Code: e8 ce 49 11 00 48 83 c4 08 4c 89 e0 5b 5d 41 5c 41 5d 41 5e 41 5f c3 44 89 f6 48 c70 [ 62.498133] RSP: 0000:ffffa96800043d40 EFLAGS: 00010086 [ 62.498391] RAX: 0000000000000000 RBX: ffff9b87fc458400 RCX: 0000000000000000 [ 62.498741] RDX: 0000000000000001 RSI: 0000000000000096 RDI: ffffffff9693d72c [ 62.499091] RBP: ffff9b87fd4c8f60 R08: ffffa96800043bfd R09: 0000000000000163 [ 62.499440] R10: ffffa96800043bf8 R11: ffffa96800043bfd R12: ffff9b87fd4c8e00 [ 62.499790] R13: ffff9b87fd4c8ea4 R14: 000000000000000b R15: ffff9b87fd76b000 [ 62.500140] FS: 0000000000000000(0000) GS:ffff9b87fdc00000(0000) knlGS:0000000000000000 [ 62.500534] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 62.500816] CR2: 0000000000000000 CR3: 000000003aa0a000 CR4: 00000000000006f0 [ 62.501165] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 62.501515] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 62.501864] Call Trace: [ 62.501993] pci_free_irq+0x13/0x20 [ 62.502167] nvme_reset_work+0x5d0/0x12a0 [ 62.502369] ? update_load_avg+0x59/0x580 [ 62.502569] ? ttwu_queue_wakelist+0xa8/0xc0 [ 62.502780] ? try_to_wake_up+0x1a2/0x450 [ 62.502979] process_one_work+0x1d2/0x390 [ 62.503179] worker_thread+0x45/0x3b0 [ 62.503361] ? process_one_work+0x390/0x390 [ 62.503568] kthread+0xf9/0x130 [ 62.503726] ? kthread_park+0x80/0x80 [ 62.503911] ret_from_fork+0x22/0x30 [ 62.504090] ---[ end trace de9ed4a70f8d71e2 ]--- [ 123.912275] nvme nvme0: I/O 12 QID 0 timeout, disable controller [ 123.914670] nvme nvme0: 1/0/0 default/read/poll queues [ 123.916310] BUG: kernel NULL pointer dereference, address: 0000000000000000 [ 123.917469] #PF: supervisor write access in kernel mode [ 123.917725] #PF: error_code(0x0002) - not-present page [ 123.917976] PGD 0 P4D 0 [ 123.918109] Oops: 0002 [#1] SMP PTI [ 123.918283] CPU: 0 PID: 7 Comm: kworker/u4:0 Tainted: G W 5.8.0+ #8 [ 123.918650] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-48-gd9c812dda519-p4 [ 123.919219] Workqueue: nvme-reset-wq nvme_reset_work [ 123.919469] RIP: 0010:__blk_mq_alloc_map_and_request+0x21/0x80 [ 123.919757] Code: 66 0f 1f 84 00 00 00 00 00 41 55 41 54 55 48 63 ee 53 48 8b 47 68 89 ee 48 89 fb 8b4 [ 123.920657] RSP: 0000:ffffa96800043d40 EFLAGS: 00010286 [ 123.920912] RAX: ffff9b87fc4fee40 RBX: ffff9b87fc8cb008 RCX: 0000000000000000 [ 123.921258] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff9b87fc618000 [ 123.921602] RBP: 0000000000000000 R08: ffff9b87fdc2c4a0 R09: ffff9b87fc616000 [ 123.921949] R10: 0000000000000000 R11: ffff9b87fffd1500 R12: 0000000000000000 [ 123.922295] R13: 0000000000000000 R14: ffff9b87fc8cb200 R15: ffff9b87fc8cb000 [ 123.922641] FS: 0000000000000000(0000) GS:ffff9b87fdc00000(0000) knlGS:0000000000000000 [ 123.923032] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 123.923312] CR2: 0000000000000000 CR3: 000000003aa0a000 CR4: 00000000000006f0 [ 123.923660] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 123.924007] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 123.924353] Call Trace: [ 123.924479] blk_mq_alloc_tag_set+0x137/0x2a0 [ 123.924694] nvme_reset_work+0xed6/0x12a0 [ 123.924898] process_one_work+0x1d2/0x390 [ 123.925099] worker_thread+0x45/0x3b0 [ 123.925280] ? process_one_work+0x390/0x390 [ 123.925486] kthread+0xf9/0x130 [ 123.925642] ? kthread_park+0x80/0x80 [ 123.925825] ret_from_fork+0x22/0x30 [ 123.926004] Modules linked in: [ 123.926158] CR2: 0000000000000000 [ 123.926322] ---[ end trace de9ed4a70f8d71e3 ]--- [ 123.926549] RIP: 0010:__blk_mq_alloc_map_and_request+0x21/0x80 [ 123.926832] Code: 66 0f 1f 84 00 00 00 00 00 41 55 41 54 55 48 63 ee 53 48 8b 47 68 89 ee 48 89 fb 8b4 [ 123.927734] RSP: 0000:ffffa96800043d40 EFLAGS: 00010286 [ 123.927989] RAX: ffff9b87fc4fee40 RBX: ffff9b87fc8cb008 RCX: 0000000000000000 [ 123.928336] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff9b87fc618000 [ 123.928679] RBP: 0000000000000000 R08: ffff9b87fdc2c4a0 R09: ffff9b87fc616000 [ 123.929025] R10: 0000000000000000 R11: ffff9b87fffd1500 R12: 0000000000000000 [ 123.929370] R13: 0000000000000000 R14: ffff9b87fc8cb200 R15: ffff9b87fc8cb000 [ 123.929715] FS: 0000000000000000(0000) GS:ffff9b87fdc00000(0000) knlGS:0000000000000000 [ 123.930106] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 123.930384] CR2: 0000000000000000 CR3: 000000003aa0a000 CR4: 00000000000006f0 [ 123.930731] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 123.931077] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Co-developed-by: Keith Busch <kbusch@kernel.org> Signed-off-by: Tong Zhang <ztong0001@gmail.com> Reviewed-by: Keith Busch <kbusch@kernel.org> Signed-off-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 22fe5a2 ] The aliases were never released causing the following leaks: Indirect leak of 1224 byte(s) in 9 object(s) allocated from: #0 0x7feefb830628 in malloc (/lib/x86_64-linux-gnu/libasan.so.5+0x107628) #1 0x56332c8f1b62 in __perf_pmu__new_alias util/pmu.c:322 #2 0x56332c8f401f in pmu_add_cpu_aliases_map util/pmu.c:778 #3 0x56332c792ce9 in __test__pmu_event_aliases tests/pmu-events.c:295 #4 0x56332c792ce9 in test_aliases tests/pmu-events.c:367 #5 0x56332c76a09b in run_test tests/builtin-test.c:410 #6 0x56332c76a09b in test_and_print tests/builtin-test.c:440 #7 0x56332c76ce69 in __cmd_test tests/builtin-test.c:695 #8 0x56332c76ce69 in cmd_test tests/builtin-test.c:807 #9 0x56332c7d2214 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312 torvalds#10 0x56332c6701a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364 torvalds#11 0x56332c6701a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408 torvalds#12 0x56332c6701a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538 torvalds#13 0x7feefb359cc9 in __libc_start_main ../csu/libc-start.c:308 Fixes: 956a783 ("perf test: Test pmu-events aliases") Signed-off-by: Namhyung Kim <namhyung@kernel.org> Reviewed-by: John Garry <john.garry@huawei.com> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lore.kernel.org/lkml/20200915031819.386559-11-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit b12eea5 ] The evsel->unit borrows a pointer of pmu event or alias instead of owns a string. But tool event (duration_time) passes a result of strdup() caused a leak. It was found by ASAN during metric test: Direct leak of 210 byte(s) in 70 object(s) allocated from: #0 0x7fe366fca0b5 in strdup (/lib/x86_64-linux-gnu/libasan.so.5+0x920b5) #1 0x559fbbcc6ea3 in add_event_tool util/parse-events.c:414 #2 0x559fbbcc6ea3 in parse_events_add_tool util/parse-events.c:1414 #3 0x559fbbd8474d in parse_events_parse util/parse-events.y:439 #4 0x559fbbcc95da in parse_events__scanner util/parse-events.c:2096 #5 0x559fbbcc95da in __parse_events util/parse-events.c:2141 #6 0x559fbbc28555 in check_parse_id tests/pmu-events.c:406 #7 0x559fbbc28555 in check_parse_id tests/pmu-events.c:393 #8 0x559fbbc28555 in check_parse_cpu tests/pmu-events.c:415 #9 0x559fbbc28555 in test_parsing tests/pmu-events.c:498 torvalds#10 0x559fbbc0109b in run_test tests/builtin-test.c:410 torvalds#11 0x559fbbc0109b in test_and_print tests/builtin-test.c:440 torvalds#12 0x559fbbc03e69 in __cmd_test tests/builtin-test.c:695 torvalds#13 0x559fbbc03e69 in cmd_test tests/builtin-test.c:807 torvalds#14 0x559fbbc691f4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312 torvalds#15 0x559fbbb071a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364 torvalds#16 0x559fbbb071a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408 torvalds#17 0x559fbbb071a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538 torvalds#18 0x7fe366b68cc9 in __libc_start_main ../csu/libc-start.c:308 Fixes: f0fbb11 ("perf stat: Implement duration_time as a proper event") Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lore.kernel.org/lkml/20200915031819.386559-6-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit d26383d ] The following leaks were detected by ASAN: Indirect leak of 360 byte(s) in 9 object(s) allocated from: #0 0x7fecc305180e in calloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10780e) #1 0x560578f6dce5 in perf_pmu__new_format util/pmu.c:1333 #2 0x560578f752fc in perf_pmu_parse util/pmu.y:59 #3 0x560578f6a8b7 in perf_pmu__format_parse util/pmu.c:73 #4 0x560578e07045 in test__pmu tests/pmu.c:155 #5 0x560578de109b in run_test tests/builtin-test.c:410 #6 0x560578de109b in test_and_print tests/builtin-test.c:440 #7 0x560578de401a in __cmd_test tests/builtin-test.c:661 #8 0x560578de401a in cmd_test tests/builtin-test.c:807 #9 0x560578e49354 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312 torvalds#10 0x560578ce71a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364 torvalds#11 0x560578ce71a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408 torvalds#12 0x560578ce71a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538 torvalds#13 0x7fecc2b7acc9 in __libc_start_main ../csu/libc-start.c:308 Fixes: cff7f95 ("perf tests: Move pmu tests into separate object") Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lore.kernel.org/lkml/20200915031819.386559-12-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit 572c83a upstream. In fstest btrfs/064 a transaction abort in __btrfs_cow_block could lead to a system lockup. It gets stuck trying to write back inodes, and the write back thread was trying to lock an extent buffer: $ cat /proc/2143497/stack [<0>] __btrfs_tree_lock+0x108/0x250 [<0>] lock_extent_buffer_for_io+0x35e/0x3a0 [<0>] btree_write_cache_pages+0x15a/0x3b0 [<0>] do_writepages+0x28/0xb0 [<0>] __writeback_single_inode+0x54/0x5c0 [<0>] writeback_sb_inodes+0x1e8/0x510 [<0>] wb_writeback+0xcc/0x440 [<0>] wb_workfn+0xd7/0x650 [<0>] process_one_work+0x236/0x560 [<0>] worker_thread+0x55/0x3c0 [<0>] kthread+0x13a/0x150 [<0>] ret_from_fork+0x1f/0x30 This is because we got an error while COWing a block, specifically here if (test_bit(BTRFS_ROOT_SHAREABLE, &root->state)) { ret = btrfs_reloc_cow_block(trans, root, buf, cow); if (ret) { btrfs_abort_transaction(trans, ret); return ret; } } [16402.241552] BTRFS: Transaction aborted (error -2) [16402.242362] WARNING: CPU: 1 PID: 2563188 at fs/btrfs/ctree.c:1074 __btrfs_cow_block+0x376/0x540 [16402.249469] CPU: 1 PID: 2563188 Comm: fsstress Not tainted 5.9.0-rc6+ #8 [16402.249936] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 [16402.250525] RIP: 0010:__btrfs_cow_block+0x376/0x540 [16402.252417] RSP: 0018:ffff9cca40e578b0 EFLAGS: 00010282 [16402.252787] RAX: 0000000000000025 RBX: 0000000000000002 RCX: ffff9132bbd19388 [16402.253278] RDX: 00000000ffffffd8 RSI: 0000000000000027 RDI: ffff9132bbd19380 [16402.254063] RBP: ffff9132b41a49c0 R08: 0000000000000000 R09: 0000000000000000 [16402.254887] R10: 0000000000000000 R11: ffff91324758b080 R12: ffff91326ef17ce0 [16402.255694] R13: ffff91325fc0f000 R14: ffff91326ef176b0 R15: ffff9132815e2000 [16402.256321] FS: 00007f542c6d7b80(0000) GS:ffff9132bbd00000(0000) knlGS:0000000000000000 [16402.256973] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [16402.257374] CR2: 00007f127b83f250 CR3: 0000000133480002 CR4: 0000000000370ee0 [16402.257867] Call Trace: [16402.258072] btrfs_cow_block+0x109/0x230 [16402.258356] btrfs_search_slot+0x530/0x9d0 [16402.258655] btrfs_lookup_file_extent+0x37/0x40 [16402.259155] __btrfs_drop_extents+0x13c/0xd60 [16402.259628] ? btrfs_block_rsv_migrate+0x4f/0xb0 [16402.259949] btrfs_replace_file_extents+0x190/0x820 [16402.260873] btrfs_clone+0x9ae/0xc00 [16402.261139] btrfs_extent_same_range+0x66/0x90 [16402.261771] btrfs_remap_file_range+0x353/0x3b1 [16402.262333] vfs_dedupe_file_range_one.part.0+0xd5/0x140 [16402.262821] vfs_dedupe_file_range+0x189/0x220 [16402.263150] do_vfs_ioctl+0x552/0x700 [16402.263662] __x64_sys_ioctl+0x62/0xb0 [16402.264023] do_syscall_64+0x33/0x40 [16402.264364] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [16402.264862] RIP: 0033:0x7f542c7d15cb [16402.266901] RSP: 002b:00007ffd35944ea8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [16402.267627] RAX: ffffffffffffffda RBX: 00000000009d1968 RCX: 00007f542c7d15cb [16402.268298] RDX: 00000000009d2490 RSI: 00000000c0189436 RDI: 0000000000000003 [16402.268958] RBP: 00000000009d2520 R08: 0000000000000036 R09: 00000000009d2e64 [16402.269726] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002 [16402.270659] R13: 000000000001f000 R14: 00000000009d1970 R15: 00000000009d2e80 [16402.271498] irq event stamp: 0 [16402.271846] hardirqs last enabled at (0): [<0000000000000000>] 0x0 [16402.272497] hardirqs last disabled at (0): [<ffffffff910dbf59>] copy_process+0x6b9/0x1ba0 [16402.273343] softirqs last enabled at (0): [<ffffffff910dbf59>] copy_process+0x6b9/0x1ba0 [16402.273905] softirqs last disabled at (0): [<0000000000000000>] 0x0 [16402.274338] ---[ end trace 737874a5a41a8236 ]--- [16402.274669] BTRFS: error (device dm-9) in __btrfs_cow_block:1074: errno=-2 No such entry [16402.276179] BTRFS info (device dm-9): forced readonly [16402.277046] BTRFS: error (device dm-9) in btrfs_replace_file_extents:2723: errno=-2 No such entry [16402.278744] BTRFS: error (device dm-9) in __btrfs_cow_block:1074: errno=-2 No such entry [16402.279968] BTRFS: error (device dm-9) in __btrfs_cow_block:1074: errno=-2 No such entry [16402.280582] BTRFS info (device dm-9): balance: ended with status: -30 The problem here is that as soon as we allocate the new block it is locked and marked dirty in the btree inode. This means that we could attempt to writeback this block and need to lock the extent buffer. However we're not unlocking it here and thus we deadlock. Fix this by unlocking the cow block if we have any errors inside of __btrfs_cow_block, and also free it so we do not leak it. CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 66d204a upstream. Very sporadically I had test case btrfs/069 from fstests hanging (for years, it is not a recent regression), with the following traces in dmesg/syslog: [162301.160628] BTRFS info (device sdc): dev_replace from /dev/sdd (devid 2) to /dev/sdg started [162301.181196] BTRFS info (device sdc): scrub: finished on devid 4 with status: 0 [162301.287162] BTRFS info (device sdc): dev_replace from /dev/sdd (devid 2) to /dev/sdg finished [162513.513792] INFO: task btrfs-transacti:1356167 blocked for more than 120 seconds. [162513.514318] Not tainted 5.9.0-rc6-btrfs-next-69 #1 [162513.514522] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [162513.514747] task:btrfs-transacti state:D stack: 0 pid:1356167 ppid: 2 flags:0x00004000 [162513.514751] Call Trace: [162513.514761] __schedule+0x5ce/0xd00 [162513.514765] ? _raw_spin_unlock_irqrestore+0x3c/0x60 [162513.514771] schedule+0x46/0xf0 [162513.514844] wait_current_trans+0xde/0x140 [btrfs] [162513.514850] ? finish_wait+0x90/0x90 [162513.514864] start_transaction+0x37c/0x5f0 [btrfs] [162513.514879] transaction_kthread+0xa4/0x170 [btrfs] [162513.514891] ? btrfs_cleanup_transaction+0x660/0x660 [btrfs] [162513.514894] kthread+0x153/0x170 [162513.514897] ? kthread_stop+0x2c0/0x2c0 [162513.514902] ret_from_fork+0x22/0x30 [162513.514916] INFO: task fsstress:1356184 blocked for more than 120 seconds. [162513.515192] Not tainted 5.9.0-rc6-btrfs-next-69 #1 [162513.515431] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [162513.515680] task:fsstress state:D stack: 0 pid:1356184 ppid:1356177 flags:0x00004000 [162513.515682] Call Trace: [162513.515688] __schedule+0x5ce/0xd00 [162513.515691] ? _raw_spin_unlock_irqrestore+0x3c/0x60 [162513.515697] schedule+0x46/0xf0 [162513.515712] wait_current_trans+0xde/0x140 [btrfs] [162513.515716] ? finish_wait+0x90/0x90 [162513.515729] start_transaction+0x37c/0x5f0 [btrfs] [162513.515743] btrfs_attach_transaction_barrier+0x1f/0x50 [btrfs] [162513.515753] btrfs_sync_fs+0x61/0x1c0 [btrfs] [162513.515758] ? __ia32_sys_fdatasync+0x20/0x20 [162513.515761] iterate_supers+0x87/0xf0 [162513.515765] ksys_sync+0x60/0xb0 [162513.515768] __do_sys_sync+0xa/0x10 [162513.515771] do_syscall_64+0x33/0x80 [162513.515774] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [162513.515781] RIP: 0033:0x7f5238f50bd7 [162513.515782] Code: Bad RIP value. [162513.515784] RSP: 002b:00007fff67b978e8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a2 [162513.515786] RAX: ffffffffffffffda RBX: 000055b1fad2c560 RCX: 00007f5238f50bd7 [162513.515788] RDX: 00000000ffffffff RSI: 000000000daf0e74 RDI: 000000000000003a [162513.515789] RBP: 0000000000000032 R08: 000000000000000a R09: 00007f5239019be0 [162513.515791] R10: fffffffffffff24f R11: 0000000000000206 R12: 000000000000003a [162513.515792] R13: 00007fff67b97950 R14: 00007fff67b97906 R15: 000055b1fad1a340 [162513.515804] INFO: task fsstress:1356185 blocked for more than 120 seconds. [162513.516064] Not tainted 5.9.0-rc6-btrfs-next-69 #1 [162513.516329] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [162513.516617] task:fsstress state:D stack: 0 pid:1356185 ppid:1356177 flags:0x00000000 [162513.516620] Call Trace: [162513.516625] __schedule+0x5ce/0xd00 [162513.516628] ? _raw_spin_unlock_irqrestore+0x3c/0x60 [162513.516634] schedule+0x46/0xf0 [162513.516647] wait_current_trans+0xde/0x140 [btrfs] [162513.516650] ? finish_wait+0x90/0x90 [162513.516662] start_transaction+0x4d7/0x5f0 [btrfs] [162513.516679] btrfs_setxattr_trans+0x3c/0x100 [btrfs] [162513.516686] __vfs_setxattr+0x66/0x80 [162513.516691] __vfs_setxattr_noperm+0x70/0x200 [162513.516697] vfs_setxattr+0x6b/0x120 [162513.516703] setxattr+0x125/0x240 [162513.516709] ? lock_acquire+0xb1/0x480 [162513.516712] ? mnt_want_write+0x20/0x50 [162513.516721] ? rcu_read_lock_any_held+0x8e/0xb0 [162513.516723] ? preempt_count_add+0x49/0xa0 [162513.516725] ? __sb_start_write+0x19b/0x290 [162513.516727] ? preempt_count_add+0x49/0xa0 [162513.516732] path_setxattr+0xba/0xd0 [162513.516739] __x64_sys_setxattr+0x27/0x30 [162513.516741] do_syscall_64+0x33/0x80 [162513.516743] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [162513.516745] RIP: 0033:0x7f5238f56d5a [162513.516746] Code: Bad RIP value. [162513.516748] RSP: 002b:00007fff67b97868 EFLAGS: 00000202 ORIG_RAX: 00000000000000bc [162513.516750] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f5238f56d5a [162513.516751] RDX: 000055b1fbb0d5a0 RSI: 00007fff67b978a0 RDI: 000055b1fbb0d470 [162513.516753] RBP: 000055b1fbb0d5a0 R08: 0000000000000001 R09: 00007fff67b97700 [162513.516754] R10: 0000000000000004 R11: 0000000000000202 R12: 0000000000000004 [162513.516756] R13: 0000000000000024 R14: 0000000000000001 R15: 00007fff67b978a0 [162513.516767] INFO: task fsstress:1356196 blocked for more than 120 seconds. [162513.517064] Not tainted 5.9.0-rc6-btrfs-next-69 #1 [162513.517365] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [162513.517763] task:fsstress state:D stack: 0 pid:1356196 ppid:1356177 flags:0x00004000 [162513.517780] Call Trace: [162513.517786] __schedule+0x5ce/0xd00 [162513.517789] ? _raw_spin_unlock_irqrestore+0x3c/0x60 [162513.517796] schedule+0x46/0xf0 [162513.517810] wait_current_trans+0xde/0x140 [btrfs] [162513.517814] ? finish_wait+0x90/0x90 [162513.517829] start_transaction+0x37c/0x5f0 [btrfs] [162513.517845] btrfs_attach_transaction_barrier+0x1f/0x50 [btrfs] [162513.517857] btrfs_sync_fs+0x61/0x1c0 [btrfs] [162513.517862] ? __ia32_sys_fdatasync+0x20/0x20 [162513.517865] iterate_supers+0x87/0xf0 [162513.517869] ksys_sync+0x60/0xb0 [162513.517872] __do_sys_sync+0xa/0x10 [162513.517875] do_syscall_64+0x33/0x80 [162513.517878] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [162513.517881] RIP: 0033:0x7f5238f50bd7 [162513.517883] Code: Bad RIP value. [162513.517885] RSP: 002b:00007fff67b978e8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a2 [162513.517887] RAX: ffffffffffffffda RBX: 000055b1fad2c560 RCX: 00007f5238f50bd7 [162513.517889] RDX: 0000000000000000 RSI: 000000007660add2 RDI: 0000000000000053 [162513.517891] RBP: 0000000000000032 R08: 0000000000000067 R09: 00007f5239019be0 [162513.517893] R10: fffffffffffff24f R11: 0000000000000206 R12: 0000000000000053 [162513.517895] R13: 00007fff67b97950 R14: 00007fff67b97906 R15: 000055b1fad1a340 [162513.517908] INFO: task fsstress:1356197 blocked for more than 120 seconds. [162513.518298] Not tainted 5.9.0-rc6-btrfs-next-69 #1 [162513.518672] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [162513.519157] task:fsstress state:D stack: 0 pid:1356197 ppid:1356177 flags:0x00000000 [162513.519160] Call Trace: [162513.519165] __schedule+0x5ce/0xd00 [162513.519168] ? _raw_spin_unlock_irqrestore+0x3c/0x60 [162513.519174] schedule+0x46/0xf0 [162513.519190] wait_current_trans+0xde/0x140 [btrfs] [162513.519193] ? finish_wait+0x90/0x90 [162513.519206] start_transaction+0x4d7/0x5f0 [btrfs] [162513.519222] btrfs_create+0x57/0x200 [btrfs] [162513.519230] lookup_open+0x522/0x650 [162513.519246] path_openat+0x2b8/0xa50 [162513.519270] do_filp_open+0x91/0x100 [162513.519275] ? find_held_lock+0x32/0x90 [162513.519280] ? lock_acquired+0x33b/0x470 [162513.519285] ? do_raw_spin_unlock+0x4b/0xc0 [162513.519287] ? _raw_spin_unlock+0x29/0x40 [162513.519295] do_sys_openat2+0x20d/0x2d0 [162513.519300] do_sys_open+0x44/0x80 [162513.519304] do_syscall_64+0x33/0x80 [162513.519307] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [162513.519309] RIP: 0033:0x7f5238f4a903 [162513.519310] Code: Bad RIP value. [162513.519312] RSP: 002b:00007fff67b97758 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 [162513.519314] RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007f5238f4a903 [162513.519316] RDX: 0000000000000000 RSI: 00000000000001b6 RDI: 000055b1fbb0d470 [162513.519317] RBP: 00007fff67b978c0 R08: 0000000000000001 R09: 0000000000000002 [162513.519319] R10: 00007fff67b974f7 R11: 0000000000000246 R12: 0000000000000013 [162513.519320] R13: 00000000000001b6 R14: 00007fff67b97906 R15: 000055b1fad1c620 [162513.519332] INFO: task btrfs:1356211 blocked for more than 120 seconds. [162513.519727] Not tainted 5.9.0-rc6-btrfs-next-69 #1 [162513.520115] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [162513.520508] task:btrfs state:D stack: 0 pid:1356211 ppid:1356178 flags:0x00004002 [162513.520511] Call Trace: [162513.520516] __schedule+0x5ce/0xd00 [162513.520519] ? _raw_spin_unlock_irqrestore+0x3c/0x60 [162513.520525] schedule+0x46/0xf0 [162513.520544] btrfs_scrub_pause+0x11f/0x180 [btrfs] [162513.520548] ? finish_wait+0x90/0x90 [162513.520562] btrfs_commit_transaction+0x45a/0xc30 [btrfs] [162513.520574] ? start_transaction+0xe0/0x5f0 [btrfs] [162513.520596] btrfs_dev_replace_finishing+0x6d8/0x711 [btrfs] [162513.520619] btrfs_dev_replace_by_ioctl.cold+0x1cc/0x1fd [btrfs] [162513.520639] btrfs_ioctl+0x2a25/0x36f0 [btrfs] [162513.520643] ? do_sigaction+0xf3/0x240 [162513.520645] ? find_held_lock+0x32/0x90 [162513.520648] ? do_sigaction+0xf3/0x240 [162513.520651] ? lock_acquired+0x33b/0x470 [162513.520655] ? _raw_spin_unlock_irq+0x24/0x50 [162513.520657] ? lockdep_hardirqs_on+0x7d/0x100 [162513.520660] ? _raw_spin_unlock_irq+0x35/0x50 [162513.520662] ? do_sigaction+0xf3/0x240 [162513.520671] ? __x64_sys_ioctl+0x83/0xb0 [162513.520672] __x64_sys_ioctl+0x83/0xb0 [162513.520677] do_syscall_64+0x33/0x80 [162513.520679] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [162513.520681] RIP: 0033:0x7fc3cd307d87 [162513.520682] Code: Bad RIP value. [162513.520684] RSP: 002b:00007ffe30a56bb8 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 [162513.520686] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fc3cd307d87 [162513.520687] RDX: 00007ffe30a57a30 RSI: 00000000ca289435 RDI: 0000000000000003 [162513.520689] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [162513.520690] R10: 0000000000000008 R11: 0000000000000202 R12: 0000000000000003 [162513.520692] R13: 0000557323a212e0 R14: 00007ffe30a5a520 R15: 0000000000000001 [162513.520703] Showing all locks held in the system: [162513.520712] 1 lock held by khungtaskd/54: [162513.520713] #0: ffffffffb40a91a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x15/0x197 [162513.520728] 1 lock held by in:imklog/596: [162513.520729] #0: ffff8f3f0d781400 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x4d/0x60 [162513.520782] 1 lock held by btrfs-transacti/1356167: [162513.520784] #0: ffff8f3d810cc848 (&fs_info->transaction_kthread_mutex){+.+.}-{3:3}, at: transaction_kthread+0x4a/0x170 [btrfs] [162513.520798] 1 lock held by btrfs/1356190: [162513.520800] #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write_file+0x22/0x60 [162513.520805] 1 lock held by fsstress/1356184: [162513.520806] #0: ffff8f3d576440e8 (&type->s_umount_key#62){++++}-{3:3}, at: iterate_supers+0x6f/0xf0 [162513.520811] 3 locks held by fsstress/1356185: [162513.520812] #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x20/0x50 [162513.520815] #1: ffff8f3d80a650b8 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: vfs_setxattr+0x50/0x120 [162513.520820] #2: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs] [162513.520833] 1 lock held by fsstress/1356196: [162513.520834] #0: ffff8f3d576440e8 (&type->s_umount_key#62){++++}-{3:3}, at: iterate_supers+0x6f/0xf0 [162513.520838] 3 locks held by fsstress/1356197: [162513.520839] #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x20/0x50 [162513.520843] #1: ffff8f3d506465e8 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: path_openat+0x2a7/0xa50 [162513.520846] #2: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs] [162513.520858] 2 locks held by btrfs/1356211: [162513.520859] #0: ffff8f3d810cde30 (&fs_info->dev_replace.lock_finishing_cancel_unmount){+.+.}-{3:3}, at: btrfs_dev_replace_finishing+0x52/0x711 [btrfs] [162513.520877] #1: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs] This was weird because the stack traces show that a transaction commit, triggered by a device replace operation, is blocking trying to pause any running scrubs but there are no stack traces of blocked tasks doing a scrub. After poking around with drgn, I noticed there was a scrub task that was constantly running and blocking for shorts periods of time: >>> t = find_task(prog, 1356190) >>> prog.stack_trace(t) #0 __schedule+0x5ce/0xcfc #1 schedule+0x46/0xe4 #2 schedule_timeout+0x1df/0x475 #3 btrfs_reada_wait+0xda/0x132 #4 scrub_stripe+0x2a8/0x112f #5 scrub_chunk+0xcd/0x134 #6 scrub_enumerate_chunks+0x29e/0x5ee #7 btrfs_scrub_dev+0x2d5/0x91b #8 btrfs_ioctl+0x7f5/0x36e7 #9 __x64_sys_ioctl+0x83/0xb0 torvalds#10 do_syscall_64+0x33/0x77 torvalds#11 entry_SYSCALL_64+0x7c/0x156 Which corresponds to: int btrfs_reada_wait(void *handle) { struct reada_control *rc = handle; struct btrfs_fs_info *fs_info = rc->fs_info; while (atomic_read(&rc->elems)) { if (!atomic_read(&fs_info->reada_works_cnt)) reada_start_machine(fs_info); wait_event_timeout(rc->wait, atomic_read(&rc->elems) == 0, (HZ + 9) / 10); } (...) So the counter "rc->elems" was set to 1 and never decreased to 0, causing the scrub task to loop forever in that function. Then I used the following script for drgn to check the readahead requests: $ cat dump_reada.py import sys import drgn from drgn import NULL, Object, cast, container_of, execscript, \ reinterpret, sizeof from drgn.helpers.linux import * mnt_path = b"/home/fdmanana/btrfs-tests/scratch_1" mnt = None for mnt in for_each_mount(prog, dst = mnt_path): pass if mnt is None: sys.stderr.write(f'Error: mount point {mnt_path} not found\n') sys.exit(1) fs_info = cast('struct btrfs_fs_info *', mnt.mnt.mnt_sb.s_fs_info) def dump_re(re): nzones = re.nzones.value_() print(f're at {hex(re.value_())}') print(f'\t logical {re.logical.value_()}') print(f'\t refcnt {re.refcnt.value_()}') print(f'\t nzones {nzones}') for i in range(nzones): dev = re.zones[i].device name = dev.name.str.string_() print(f'\t\t dev id {dev.devid.value_()} name {name}') print() for _, e in radix_tree_for_each(fs_info.reada_tree): re = cast('struct reada_extent *', e) dump_re(re) $ drgn dump_reada.py re at 0xffff8f3da9d25ad8 logical 38928384 refcnt 1 nzones 1 dev id 0 name b'/dev/sdd' $ So there was one readahead extent with a single zone corresponding to the source device of that last device replace operation logged in dmesg/syslog. Also the ID of that zone's device was 0 which is a special value set in the source device of a device replace operation when the operation finishes (constant BTRFS_DEV_REPLACE_DEVID set at btrfs_dev_replace_finishing()), confirming again that device /dev/sdd was the source of a device replace operation. Normally there should be as many zones in the readahead extent as there are devices, and I wasn't expecting the extent to be in a block group with a 'single' profile, so I went and confirmed with the following drgn script that there weren't any single profile block groups: $ cat dump_block_groups.py import sys import drgn from drgn import NULL, Object, cast, container_of, execscript, \ reinterpret, sizeof from drgn.helpers.linux import * mnt_path = b"/home/fdmanana/btrfs-tests/scratch_1" mnt = None for mnt in for_each_mount(prog, dst = mnt_path): pass if mnt is None: sys.stderr.write(f'Error: mount point {mnt_path} not found\n') sys.exit(1) fs_info = cast('struct btrfs_fs_info *', mnt.mnt.mnt_sb.s_fs_info) BTRFS_BLOCK_GROUP_DATA = (1 << 0) BTRFS_BLOCK_GROUP_SYSTEM = (1 << 1) BTRFS_BLOCK_GROUP_METADATA = (1 << 2) BTRFS_BLOCK_GROUP_RAID0 = (1 << 3) BTRFS_BLOCK_GROUP_RAID1 = (1 << 4) BTRFS_BLOCK_GROUP_DUP = (1 << 5) BTRFS_BLOCK_GROUP_RAID10 = (1 << 6) BTRFS_BLOCK_GROUP_RAID5 = (1 << 7) BTRFS_BLOCK_GROUP_RAID6 = (1 << 8) BTRFS_BLOCK_GROUP_RAID1C3 = (1 << 9) BTRFS_BLOCK_GROUP_RAID1C4 = (1 << 10) def bg_flags_string(bg): flags = bg.flags.value_() ret = '' if flags & BTRFS_BLOCK_GROUP_DATA: ret = 'data' if flags & BTRFS_BLOCK_GROUP_METADATA: if len(ret) > 0: ret += '|' ret += 'meta' if flags & BTRFS_BLOCK_GROUP_SYSTEM: if len(ret) > 0: ret += '|' ret += 'system' if flags & BTRFS_BLOCK_GROUP_RAID0: ret += ' raid0' elif flags & BTRFS_BLOCK_GROUP_RAID1: ret += ' raid1' elif flags & BTRFS_BLOCK_GROUP_DUP: ret += ' dup' elif flags & BTRFS_BLOCK_GROUP_RAID10: ret += ' raid10' elif flags & BTRFS_BLOCK_GROUP_RAID5: ret += ' raid5' elif flags & BTRFS_BLOCK_GROUP_RAID6: ret += ' raid6' elif flags & BTRFS_BLOCK_GROUP_RAID1C3: ret += ' raid1c3' elif flags & BTRFS_BLOCK_GROUP_RAID1C4: ret += ' raid1c4' else: ret += ' single' return ret def dump_bg(bg): print() print(f'block group at {hex(bg.value_())}') print(f'\t start {bg.start.value_()} length {bg.length.value_()}') print(f'\t flags {bg.flags.value_()} - {bg_flags_string(bg)}') bg_root = fs_info.block_group_cache_tree.address_of_() for bg in rbtree_inorder_for_each_entry('struct btrfs_block_group', bg_root, 'cache_node'): dump_bg(bg) $ drgn dump_block_groups.py block group at 0xffff8f3d673b0400 start 22020096 length 16777216 flags 258 - system raid6 block group at 0xffff8f3d53ddb400 start 38797312 length 536870912 flags 260 - meta raid6 block group at 0xffff8f3d5f4d9c00 start 575668224 length 2147483648 flags 257 - data raid6 block group at 0xffff8f3d08189000 start 2723151872 length 67108864 flags 258 - system raid6 block group at 0xffff8f3db70ff000 start 2790260736 length 1073741824 flags 260 - meta raid6 block group at 0xffff8f3d5f4dd800 start 3864002560 length 67108864 flags 258 - system raid6 block group at 0xffff8f3d67037000 start 3931111424 length 2147483648 flags 257 - data raid6 $ So there were only 2 reasons left for having a readahead extent with a single zone: reada_find_zone(), called when creating a readahead extent, returned NULL either because we failed to find the corresponding block group or because a memory allocation failed. With some additional and custom tracing I figured out that on every further ocurrence of the problem the block group had just been deleted when we were looping to create the zones for the readahead extent (at reada_find_extent()), so we ended up with only one zone in the readahead extent, corresponding to a device that ends up getting replaced. So after figuring that out it became obvious why the hang happens: 1) Task A starts a scrub on any device of the filesystem, except for device /dev/sdd; 2) Task B starts a device replace with /dev/sdd as the source device; 3) Task A calls btrfs_reada_add() from scrub_stripe() and it is currently starting to scrub a stripe from block group X. This call to btrfs_reada_add() is the one for the extent tree. When btrfs_reada_add() calls reada_add_block(), it passes the logical address of the extent tree's root node as its 'logical' argument - a value of 38928384; 4) Task A then enters reada_find_extent(), called from reada_add_block(). It finds there isn't any existing readahead extent for the logical address 38928384, so it proceeds to the path of creating a new one. It calls btrfs_map_block() to find out which stripes exist for the block group X. On the first iteration of the for loop that iterates over the stripes, it finds the stripe for device /dev/sdd, so it creates one zone for that device and adds it to the readahead extent. Before getting into the second iteration of the loop, the cleanup kthread deletes block group X because it was empty. So in the iterations for the remaining stripes it does not add more zones to the readahead extent, because the calls to reada_find_zone() returned NULL because they couldn't find block group X anymore. As a result the new readahead extent has a single zone, corresponding to the device /dev/sdd; 4) Before task A returns to btrfs_reada_add() and queues the readahead job for the readahead work queue, task B finishes the device replace and at btrfs_dev_replace_finishing() swaps the device /dev/sdd with the new device /dev/sdg; 5) Task A returns to reada_add_block(), which increments the counter "->elems" of the reada_control structure allocated at btrfs_reada_add(). Then it returns back to btrfs_reada_add() and calls reada_start_machine(). This queues a job in the readahead work queue to run the function reada_start_machine_worker(), which calls __reada_start_machine(). At __reada_start_machine() we take the device list mutex and for each device found in the current device list, we call reada_start_machine_dev() to start the readahead work. However at this point the device /dev/sdd was already freed and is not in the device list anymore. This means the corresponding readahead for the extent at 38928384 is never started, and therefore the "->elems" counter of the reada_control structure allocated at btrfs_reada_add() never goes down to 0, causing the call to btrfs_reada_wait(), done by the scrub task, to wait forever. Note that the readahead request can be made either after the device replace started or before it started, however in pratice it is very unlikely that a device replace is able to start after a readahead request is made and is able to complete before the readahead request completes - maybe only on a very small and nearly empty filesystem. This hang however is not the only problem we can have with readahead and device removals. When the readahead extent has other zones other than the one corresponding to the device that is being removed (either by a device replace or a device remove operation), we risk having a use-after-free on the device when dropping the last reference of the readahead extent. For example if we create a readahead extent with two zones, one for the device /dev/sdd and one for the device /dev/sde: 1) Before the readahead worker starts, the device /dev/sdd is removed, and the corresponding btrfs_device structure is freed. However the readahead extent still has the zone pointing to the device structure; 2) When the readahead worker starts, it only finds device /dev/sde in the current device list of the filesystem; 3) It starts the readahead work, at reada_start_machine_dev(), using the device /dev/sde; 4) Then when it finishes reading the extent from device /dev/sde, it calls __readahead_hook() which ends up dropping the last reference on the readahead extent through the last call to reada_extent_put(); 5) At reada_extent_put() it iterates over each zone of the readahead extent and attempts to delete an element from the device's 'reada_extents' radix tree, resulting in a use-after-free, as the device pointer of the zone for /dev/sdd is now stale. We can also access the device after dropping the last reference of a zone, through reada_zone_release(), also called by reada_extent_put(). And a device remove suffers the same problem, however since it shrinks the device size down to zero before removing the device, it is very unlikely to still have readahead requests not completed by the time we free the device, the only possibility is if the device has a very little space allocated. While the hang problem is exclusive to scrub, since it is currently the only user of btrfs_reada_add() and btrfs_reada_wait(), the use-after-free problem affects any path that triggers readhead, which includes btree_readahead_hook() and __readahead_hook() (a readahead worker can trigger readahed for the children of a node) for example - any path that ends up calling reada_add_block() can trigger the use-after-free after a device is removed. So fix this by waiting for any readahead requests for a device to complete before removing a device, ensuring that while waiting for existing ones no new ones can be made. This problem has been around for a very long time - the readahead code was added in 2011, device remove exists since 2008 and device replace was introduced in 2013, hard to pick a specific commit for a git Fixes tag. CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit e773ca7 ] Actually, burst size is equal to '1 << desc->rqcfg.brst_size'. we should use burst size, not desc->rqcfg.brst_size. dma memcpy performance on Rockchip RV1126 @ 1512MHz A7, 1056MHz LPDDR3, 200MHz DMA: dmatest: /# echo dma0chan0 > /sys/module/dmatest/parameters/channel /# echo 4194304 > /sys/module/dmatest/parameters/test_buf_size /# echo 8 > /sys/module/dmatest/parameters/iterations /# echo y > /sys/module/dmatest/parameters/norandom /# echo y > /sys/module/dmatest/parameters/verbose /# echo 1 > /sys/module/dmatest/parameters/run dmatest: dma0chan0-copy0: result #1: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 dmatest: dma0chan0-copy0: result #2: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 dmatest: dma0chan0-copy0: result #3: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 dmatest: dma0chan0-copy0: result #4: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 dmatest: dma0chan0-copy0: result #5: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 dmatest: dma0chan0-copy0: result #6: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 dmatest: dma0chan0-copy0: result #7: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 dmatest: dma0chan0-copy0: result #8: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000 Before: dmatest: dma0chan0-copy0: summary 8 tests, 0 failures 48 iops 200338 KB/s (0) After this patch: dmatest: dma0chan0-copy0: summary 8 tests, 0 failures 179 iops 734873 KB/s (0) After this patch and increase dma clk to 400MHz: dmatest: dma0chan0-copy0: summary 8 tests, 0 failures 259 iops 1062929 KB/s (0) Signed-off-by: Sugar Zhang <sugar.zhang@rock-chips.com> Link: https://lore.kernel.org/r/1605326106-55681-1-git-send-email-sugar.zhang@rock-chips.com Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
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I came across this problem while trying to build your kernel within buildroot.
ie. "make am335x-bone.dtb" also need the -@ switch to insert symbols in the resulting dtb just like "make dtbs" does