This is a note to let you know that I've just added the patch titled drm/i915/guc: Unwind context requests in reverse order to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-i915-guc-unwind-context-requests-in-reverse-order.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From c39f51cc980dd918c5b3da61d54c4725785e766e Mon Sep 17 00:00:00 2001 From: Matthew Brost <matthew.brost@xxxxxxxxx> Date: Thu, 9 Sep 2021 09:47:24 -0700 Subject: drm/i915/guc: Unwind context requests in reverse order From: Matthew Brost <matthew.brost@xxxxxxxxx> commit c39f51cc980dd918c5b3da61d54c4725785e766e upstream. When unwinding requests on a reset context, if other requests in the context are in the priority list the requests could be resubmitted out of seqno order. Traverse the list of active requests in reverse and append to the head of the priority list to fix this. Fixes: eb5e7da736f3 ("drm/i915/guc: Reset implementation for new GuC interface") Signed-off-by: Matthew Brost <matthew.brost@xxxxxxxxx> Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@xxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: John Harrison <John.C.Harrison@xxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-4-matthew.brost@xxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c @@ -807,9 +807,9 @@ __unwind_incomplete_requests(struct inte spin_lock_irqsave(&sched_engine->lock, flags); spin_lock(&ce->guc_active.lock); - list_for_each_entry_safe(rq, rn, - &ce->guc_active.requests, - sched.link) { + list_for_each_entry_safe_reverse(rq, rn, + &ce->guc_active.requests, + sched.link) { if (i915_request_completed(rq)) continue; @@ -824,7 +824,7 @@ __unwind_incomplete_requests(struct inte } GEM_BUG_ON(i915_sched_engine_is_empty(sched_engine)); - list_add_tail(&rq->sched.link, pl); + list_add(&rq->sched.link, pl); set_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags); } spin_unlock(&ce->guc_active.lock); Patches currently in stable-queue which might be from matthew.brost@xxxxxxxxx are queue-5.15/drm-i915-guc-don-t-drop-ce-guc_active.lock-when-unwinding-context.patch queue-5.15/drm-i915-guc-workaround-reset-g2h-is-received-after-schedule-done-g2h.patch queue-5.15/drm-i915-guc-fix-outstanding-g2h-accounting.patch queue-5.15/drm-i915-guc-don-t-enable-scheduling-on-a-banned-context-guc_id-invalid-not-registered.patch queue-5.15/drm-i915-guc-unwind-context-requests-in-reverse-order.patch