From 6b75262941b55960e2f73d93f85020fa6c9c2d2f Mon Sep 17 00:00:00 2001 From: Bas Nieuwenhuizen Date: Sat, 29 Aug 2020 03:25:02 +0200 Subject: [PATCH] radv: Fix threading issue with submission refcounts. If decrement == 0 then: - it isn't safe to access the submission - even if it is, checking that the result of the atomic_sub is 0 doesn't given an unique owner anymore. So skip it. The submission always starts out with refcount >= 1, so first one to decrement to 0 still get dibs on executing it. Fixes: 4aa75bb3bdd "radv: Add wait-before-submit support for timelines." Reviewed-by: Samuel Pitoiset Part-of: --- src/amd/vulkan/radv_device.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/src/amd/vulkan/radv_device.c b/src/amd/vulkan/radv_device.c index b0eba6abe86..90167a9d603 100644 --- a/src/amd/vulkan/radv_device.c +++ b/src/amd/vulkan/radv_device.c @@ -4414,6 +4414,12 @@ radv_queue_enqueue_submission(struct radv_deferred_queue_submission *submission, * submitted, but if the queue was empty, we decrement ourselves as there is no previous * submission. */ uint32_t decrement = submission->wait_semaphore_count - wait_cnt + (is_first ? 1 : 0); + + /* if decrement is zero, then we don't have a refcounted reference to the + * submission anymore, so it is not safe to access the submission. */ + if (!decrement) + return VK_SUCCESS; + return radv_queue_trigger_submission(submission, decrement, processing_list); }