From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1E486295DBD for ; Tue, 29 Jul 2025 16:44:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753807453; cv=none; b=jKKYFqaCxyG0sOGUmR6OlUdHGpAglDXKxQdx6oWksZ9y4g3Lk9i+1W+cp+KGFpeKFf3LJlSTxe7tDZDSBy9thRNSfSfe9Fu87Tc/g3Dl04HLw5cTJdHeJj6/vG6ByL3wGiSy2t3bLM5QoC5/bgXT/mZ9pIfkBYK2CFxU2t0t/Y8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753807453; c=relaxed/simple; bh=P4PO7hIXRxCEJ9+2jhEtCbbA9FNlK4s7CH+bzTff/vI=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=aN32kLgO5sxr+Di4viXBYaTdDFVnduBShwNGQEC2EIYSbqoXlQOBQcj3S4iCTynRhTD6FNpkAap8Ke9Noyo3AuuA1TGlDVblFf1TGvhmawo5LVKIEPwqCdrInXN+CGCE8ZcH6hXF+FyBwaDsU6MDZfecXwChtSeGNeed/BgEXKQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=kOhEh82M; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="kOhEh82M" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8B93DC4CEEF; Tue, 29 Jul 2025 16:44:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1753807452; bh=P4PO7hIXRxCEJ9+2jhEtCbbA9FNlK4s7CH+bzTff/vI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kOhEh82MX6xmtjvByi8t8bfWuSq81W1AGHkZvyGh7fLon7WXLuRvy25xcwfPKznsC C3QINldcAbCX2IGf4yfk6sq0WCTgSCmv8jWhWtXGZLtbYYuzhax4K+c1hN7gQnXDEC 8mOAD7zf82G2X0ByIRpqN/P+SmFSfvsXpt6NT+ixljKu+Qzhq5+arLVUDcy7NEBKv+ 9OhxVgZ/eijR7DEbDyXQ7q2h18XjWp8dwV9+ume8VWgifJo4ttWhTYgfQ4dP9hgejr j3bbnE0W8MfK2le3kEptXux8/3fI5Lh4/KsM5jjfLvzLHMLiNBKjhQhcMvjNSdlV0E srp8aufuX9L8Q== From: Sasha Levin To: stable@vger.kernel.org Cc: "Lin.Cao" , =?UTF-8?q?Christian=20K=C3=B6nig?= , Philipp Stanner , Sasha Levin Subject: [PATCH 5.10.y] drm/sched: Remove optimization that causes hang when killing dependent jobs Date: Tue, 29 Jul 2025 12:44:08 -0400 Message-Id: <20250729164408.2790772-1-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <2025072854-humbling-collector-aca6@gregkh> References: <2025072854-humbling-collector-aca6@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: "Lin.Cao" [ Upstream commit 15f77764e90a713ee3916ca424757688e4f565b9 ] When application A submits jobs and application B submits a job with a dependency on A's fence, the normal flow wakes up the scheduler after processing each job. However, the optimization in drm_sched_entity_add_dependency_cb() uses a callback that only clears dependencies without waking up the scheduler. When application A is killed before its jobs can run, the callback gets triggered but only clears the dependency without waking up the scheduler, causing the scheduler to enter sleep state and application B to hang. Remove the optimization by deleting drm_sched_entity_clear_dep() and its usage, ensuring the scheduler is always woken up when dependencies are cleared. Fixes: 777dbd458c89 ("drm/amdgpu: drop a dummy wakeup scheduler") Cc: stable@vger.kernel.org # v4.6+ Signed-off-by: Lin.Cao Reviewed-by: Christian König Signed-off-by: Philipp Stanner Link: https://lore.kernel.org/r/20250717084453.921097-1-lincao12@amd.com [ adjust context ] Signed-off-by: Sasha Levin --- drivers/gpu/drm/scheduler/sched_entity.c | 23 ++--------------------- 1 file changed, 2 insertions(+), 21 deletions(-) diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c index 750d91370c8a..259bcb3aec7d 100644 --- a/drivers/gpu/drm/scheduler/sched_entity.c +++ b/drivers/gpu/drm/scheduler/sched_entity.c @@ -313,19 +313,6 @@ void drm_sched_entity_destroy(struct drm_sched_entity *entity) } EXPORT_SYMBOL(drm_sched_entity_destroy); -/** - * drm_sched_entity_clear_dep - callback to clear the entities dependency - */ -static void drm_sched_entity_clear_dep(struct dma_fence *f, - struct dma_fence_cb *cb) -{ - struct drm_sched_entity *entity = - container_of(cb, struct drm_sched_entity, cb); - - entity->dependency = NULL; - dma_fence_put(f); -} - /** * drm_sched_entity_clear_dep - callback to clear the entities dependency and * wake up scheduler @@ -336,7 +323,8 @@ static void drm_sched_entity_wakeup(struct dma_fence *f, struct drm_sched_entity *entity = container_of(cb, struct drm_sched_entity, cb); - drm_sched_entity_clear_dep(f, cb); + entity->dependency = NULL; + dma_fence_put(f); drm_sched_wakeup(entity->rq->sched); } @@ -392,13 +380,6 @@ static bool drm_sched_entity_add_dependency_cb(struct drm_sched_entity *entity) fence = dma_fence_get(&s_fence->scheduled); dma_fence_put(entity->dependency); entity->dependency = fence; - if (!dma_fence_add_callback(fence, &entity->cb, - drm_sched_entity_clear_dep)) - return true; - - /* Ignore it when it is already scheduled */ - dma_fence_put(fence); - return false; } if (!dma_fence_add_callback(entity->dependency, &entity->cb, -- 2.39.5