dma-buf: Make locking consistent in dma_buf_detach()

The dma_buf_detach() locks attach->dmabuf->resv and then unlocks
dmabuf->resv, which could be a two different locks from a static
code checker perspective. In particular this triggers Smatch to
report the "double unlock" error. Make the locking pointers consistent.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://lore.kernel.org/dri-devel/Y1fLfsccW3AS%2Fo+%2F@kili/
Fixes: 809d9c72c2 ("dma-buf: Move dma_buf_attach() to dynamic locking specification")
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221030154412.8320-2-dmitry.osipenko@collabora.com
This commit is contained in:
Dmitry Osipenko 2022-10-30 18:44:11 +03:00
parent 387659939c
commit d3292daee3

View File

@ -995,10 +995,10 @@ static void __unmap_dma_buf(struct dma_buf_attachment *attach,
*/
void dma_buf_detach(struct dma_buf *dmabuf, struct dma_buf_attachment *attach)
{
if (WARN_ON(!dmabuf || !attach))
if (WARN_ON(!dmabuf || !attach || dmabuf != attach->dmabuf))
return;
dma_resv_lock(attach->dmabuf->resv, NULL);
dma_resv_lock(dmabuf->resv, NULL);
if (attach->sgt) {