Commit 3b401e30 authored by Karolina Stolarek's avatar Karolina Stolarek Committed by Christian König
Browse files

drm/ttm: Reorder sys manager cleanup step 



With the current cleanup flow, we could trigger a NULL pointer
dereference if there is a delayed destruction of a BO with a
system resource that gets executed on drain_workqueue() call,
as we attempt to free a resource using an already released
resource manager.

Remove the device from the device list and drain its workqueue
before releasing the system domain manager in ttm_device_fini().

Signed-off-by: default avatarKarolina Stolarek <karolina.stolarek@intel.com>
Reviewed-by: default avatarChristian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231016121525.2237838-1-karolina.stolarek@intel.com


Signed-off-by: default avatarChristian König <christian.koenig@amd.com>
parent 4366faf4

drivers/gpu/drm/ttm/ttm_device.c

+4 −4
Original line number Diff line number Diff line
@@ -232,10 +232,6 @@ void ttm_device_fini(struct ttm_device *bdev) 
	struct ttm_resource_manager *man;

	unsigned i;



	man = ttm_manager_type(bdev, TTM_PL_SYSTEM);

	ttm_resource_manager_set_used(man, false);

	ttm_set_driver_manager(bdev, TTM_PL_SYSTEM, NULL);



	mutex_lock(&ttm_global_mutex);

	list_del(&bdev->device_list);

	mutex_unlock(&ttm_global_mutex);
@@ -243,6 +239,10 @@ void ttm_device_fini(struct ttm_device *bdev) 
	drain_workqueue(bdev->wq);

	destroy_workqueue(bdev->wq);



	man = ttm_manager_type(bdev, TTM_PL_SYSTEM);

	ttm_resource_manager_set_used(man, false);

	ttm_set_driver_manager(bdev, TTM_PL_SYSTEM, NULL);



	spin_lock(&bdev->lru_lock);

	for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i)

		if (list_empty(&man->lru[0]))