drm/radeon: Revert: "use GEM references instead of TTMs"

Commit fd69ef0 ("drm/radeon: use GEM references instead of TTMs") causes a black screen at boot instead of showing the GDM login screen (the system is still alive). dmesg shows the following oops (abbreviated) when this happens: [ 29.315203] BUG: kernel NULL pointer dereference, address: 0000000000000000 [ 29.315209] #PF: supervisor read access in kernel mode [ 29.315213] #PF: error_code(0x0000) - not-present page [ 29.315215] PGD 0 P4D 0 [ 29.315220] Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI [ 29.315225] CPU: 0 UID: 42 PID: 2253 Comm: Xwayland Tainted: G 6.12.0-rc1+ torvalds#159 [ 29.315232] Hardware name: Micro-Star International Co., Ltd. MS-7C95/B550M PRO-VDH WIFI (MS-7C95), BIOS 2.L0 07/18/2024 [ 29.315234] RIP: 0010:drm_gem_object_free+0xc/0x20 [ 29.315272] Call Trace: [ 29.315274] <TASK> [ 29.315305] ? asm_exc_page_fault+0x22/0x30 [ 29.315315] ? drm_gem_object_free+0xc/0x20 [ 29.315320] radeon_bo_unref+0x50/0x60 [radeon] [ 29.315337] radeon_vm_fini+0x1ca/0x350 [radeon] [ 29.315356] radeon_driver_postclose_kms+0x16d/0x180 [radeon] [ 29.315370] drm_file_free+0x229/0x280 [ 29.315377] drm_release+0x5f/0xe0 [ 29.315381] __fput+0xfc/0x2c0 Revert the change to restore things back to working order. Fixes: fd69ef0 ("drm/radeon: use GEM references instead of TTMs") Signed-off-by: Hans de Goede <hdegoede@redhat.com>
intel-lab-lkp · Oct 3, 2024 · 3a699a5 · 3a699a5
1 parent b2146ed
commit 3a699a5
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Showing 2 changed files with 6 additions and 3 deletions.
diff --git a/drivers/gpu/drm/radeon/radeon_gem.c b/drivers/gpu/drm/radeon/radeon_gem.c
@@ -88,7 +88,7 @@ static void radeon_gem_object_free(struct drm_gem_object *gobj)
 
 	if (robj) {
 		radeon_mn_unregister(robj);
-		ttm_bo_put(&robj->tbo);
+		radeon_bo_unref(&robj);
 	}
 }
 

diff --git a/drivers/gpu/drm/radeon/radeon_object.c b/drivers/gpu/drm/radeon/radeon_object.c
@@ -256,15 +256,18 @@ struct radeon_bo *radeon_bo_ref(struct radeon_bo *bo)
 	if (bo == NULL)
 		return NULL;
 
-	drm_gem_object_get(&bo->tbo.base);
+	ttm_bo_get(&bo->tbo);
 	return bo;
 }
 
 void radeon_bo_unref(struct radeon_bo **bo)
 {
+	struct ttm_buffer_object *tbo;
+
 	if ((*bo) == NULL)
 		return;
-	drm_gem_object_put(&(*bo)->tbo.base);
+	tbo = &((*bo)->tbo);
+	ttm_bo_put(tbo);
 	*bo = NULL;
 }