Am Mittwoch, dem 29.01.2025 um 11:58 +0100 schrieb Christian König:

Even the kerneldoc says that with a zero timeout the function should not wait for anything, but still return 1 to indicate that the fences are signaled now.

Unfortunately that isn't what was implemented, instead of only returning 1 we also waited for at least one jiffies.

Fix that by adjusting the handling to what the function is actually documented to do.

v2: improve code readability

Reported-by: Marek Olšák marek.olsak@amd.com Reported-by: Lucas Stach l.stach@pengutronix.de Signed-off-by: Christian König christian.koenig@amd.com Cc: stable@vger.kernel.org

Reviewed-by: Lucas Stach l.stach@pengutronix.de

---

drivers/dma-buf/dma-resv.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/dma-buf/dma-resv.c b/drivers/dma-buf/dma-resv.c index 5f8d010516f0..c78cdae3deaf 100644 --- a/drivers/dma-buf/dma-resv.c +++ b/drivers/dma-buf/dma-resv.c @@ -684,11 +684,13 @@ long dma_resv_wait_timeout(struct dma_resv *obj, enum dma_resv_usage usage, dma_resv_iter_begin(&cursor, obj, usage); dma_resv_for_each_fence_unlocked(&cursor, fence) {

• ret = dma_fence_wait_timeout(fence, intr, ret);
  

• if (ret <= 0) {
  

• 	dma_resv_iter_end(&cursor);
  

• 	return ret;
  

• }
  

• ret = dma_fence_wait_timeout(fence, intr, timeout);
  

• if (ret <= 0)
  

• 	break;
  

• /* Even for zero timeout the return value is 1 */
  

• if (timeout)
  

• 	timeout = ret;
  

  } dma_resv_iter_end(&cursor);