From 2b95a7db6e0f75587bffddbb490399cbb87e4985 Mon Sep 17 00:00:00 2001 From: =?utf8?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=utf8 Content-Transfer-Encoding: 8bit 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 --- 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 b1ef4546346d..bea3e9858aca 100644 --- a/drivers/dma-buf/dma-resv.c +++ b/drivers/dma-buf/dma-resv.c @@ -685,11 +685,13 @@ 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); -- 2.25.1