From b96d700a2adf3c55ef427b1b56039ef286e61403 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Christian=20K=C3=B6nig?= Date: Tue, 28 Jan 2025 10:47:48 +0100 Subject: [PATCH] dma-buf: fix timeout handling in dma_resv_wait_timeout v2 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit [ Upstream commit 2b95a7db6e0f75587bffddbb490399cbb87e4985 ] 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 Reported-by: Lucas Stach Signed-off-by: Christian König Reviewed-by: Lucas Stach Cc: Link: https://lore.kernel.org/r/20250129105841.1806-1-christian.koenig@amd.com Signed-off-by: Sasha Levin --- drivers/dma-buf/dma-resv.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/dma-buf/dma-resv.c b/drivers/dma-buf/dma-resv.c index 242a9ec295cf..f00ecbaa7868 100644 --- a/drivers/dma-buf/dma-resv.c +++ b/drivers/dma-buf/dma-resv.c @@ -558,10 +558,13 @@ retry: goto retry; } - ret = dma_fence_wait_timeout(fence, intr, ret); + ret = dma_fence_wait_timeout(fence, intr, timeout); dma_fence_put(fence); if (ret > 0 && wait_all && (i + 1 < shared_count)) goto retry; + /* Even for zero timeout the return value is 1 */ + if (ret > 0 && timeout == 0) + ret = 1; } return ret;