Commit ceb9a321 authored by Christian König's avatar Christian König Committed by Alex Deucher
Browse files

drm/amdgpu: fix tear down order in amdgpu_vm_pt_free 



When freeing PD/PT with shadows it can happen that the shadow
destruction races with detaching the PD/PT from the VM causing a NULL
pointer dereference in the invalidation code.

Fix this by detaching the the PD/PT from the VM first and then
freeing the shadow instead.

Signed-off-by: default avatarChristian König <christian.koenig@amd.com>
Fixes: https://gitlab.freedesktop.org/drm/amd/-/issues/2867


Cc: <stable@vger.kernel.org>
Reviewed-by: default avatarAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 2c7300d3

drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c

+2 −1
Original line number Diff line number Diff line
@@ -642,13 +642,14 @@ static void amdgpu_vm_pt_free(struct amdgpu_vm_bo_base *entry) 


	if (!entry->bo)

		return;



	entry->bo->vm_bo = NULL;

	shadow = amdgpu_bo_shadowed(entry->bo);

	if (shadow) {

		ttm_bo_set_bulk_move(&shadow->tbo, NULL);

		amdgpu_bo_unref(&shadow);

	}

	ttm_bo_set_bulk_move(&entry->bo->tbo, NULL);

	entry->bo->vm_bo = NULL;



	spin_lock(&entry->vm->status_lock);

	list_del(&entry->vm_status);