drm/radeon: add extra check in radeon_ttm_tt_unpin_userptr

We somehow try to free the SG table twice.

Bugs: https://bugs.freedesktop.org/show_bug.cgi?id=89734

Signed-off-by: Christian König <christian.koenig@amd.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
Christian König 2015-03-31 17:36:57 +02:00 committed by Alex Deucher
parent 91fd89660b
commit 863653fed0

View File

@ -598,6 +598,10 @@ static void radeon_ttm_tt_unpin_userptr(struct ttm_tt *ttm)
enum dma_data_direction direction = write ?
DMA_BIDIRECTIONAL : DMA_TO_DEVICE;
/* double check that we don't free the table twice */
if (!ttm->sg->sgl)
return;
/* free the sg table and pages again */
dma_unmap_sg(rdev->dev, ttm->sg->sgl, ttm->sg->nents, direction);