From 785dcb14ec94073598fbc1ea0965901a8fca0634 Mon Sep 17 00:00:00 2001 From: Lad Prabhakar Date: Wed, 1 Jul 2020 16:41:40 +0100 Subject: [PATCH] serial: sh-sci: Initialize spinlock for uart console commit f38278e9b810b06aff2981d505267be984423ba3 upstream. serial core expects the spinlock to be initialized by the controller driver for serial console, this patch makes sure the spinlock is initialized, fixing the below issue: [ 0.865928] BUG: spinlock bad magic on CPU#0, swapper/0/1 [ 0.865945] lock: sci_ports+0x0/0x4c80, .magic: 00000000, .owner: /-1, .owner_cpu: 0 [ 0.865955] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.8.0-rc1+ #112 [ 0.865961] Hardware name: HopeRun HiHope RZ/G2H with sub board (DT) [ 0.865968] Call trace: [ 0.865979] dump_backtrace+0x0/0x1d8 [ 0.865985] show_stack+0x14/0x20 [ 0.865996] dump_stack+0xe8/0x130 [ 0.866006] spin_dump+0x6c/0x88 [ 0.866012] do_raw_spin_lock+0xb0/0xf8 [ 0.866023] _raw_spin_lock_irqsave+0x80/0xa0 [ 0.866032] uart_add_one_port+0x3a4/0x4e0 [ 0.866039] sci_probe+0x504/0x7c8 [ 0.866048] platform_drv_probe+0x50/0xa0 [ 0.866059] really_probe+0xdc/0x330 [ 0.866066] driver_probe_device+0x58/0xb8 [ 0.866072] device_driver_attach+0x6c/0x90 [ 0.866078] __driver_attach+0x88/0xd0 [ 0.866085] bus_for_each_dev+0x74/0xc8 [ 0.866091] driver_attach+0x20/0x28 [ 0.866098] bus_add_driver+0x14c/0x1f8 [ 0.866104] driver_register+0x60/0x110 [ 0.866109] __platform_driver_register+0x40/0x48 [ 0.866119] sci_init+0x2c/0x34 [ 0.866127] do_one_initcall+0x88/0x428 [ 0.866137] kernel_init_freeable+0x2c0/0x328 [ 0.866143] kernel_init+0x10/0x108 [ 0.866150] ret_from_fork+0x10/0x18 Signed-off-by: Lad Prabhakar Reviewed-by: Biju Das Fixes: a3cb39d258ef ("serial: core: Allow detach and attach serial device for console") Cc: stable Link: https://lore.kernel.org/r/1593618100-2151-1-git-send-email-prabhakar.mahadev-lad.rj@bp.renesas.com Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/sh-sci.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c index e1179e74a2b89d..204bb68ce3ca91 100644 --- a/drivers/tty/serial/sh-sci.c +++ b/drivers/tty/serial/sh-sci.c @@ -3301,6 +3301,9 @@ static int sci_probe_single(struct platform_device *dev, sciport->port.flags |= UPF_HARD_FLOW; } + if (sci_uart_driver.cons->index == sciport->port.line) + spin_lock_init(&sciport->port.lock); + ret = uart_add_one_port(&sci_uart_driver, &sciport->port); if (ret) { sci_cleanup_single(sciport);