From 0e58de9fc939e7552808f267bffde0b31feaf08a Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Mon, 4 Jan 2021 11:51:43 +0000 Subject: [PATCH] drm/i915/gt: Check the virtual still matches upon locking If another sibling is able to claim the virtual request, by the time we inspect the request under the lock it may no longer match the local engine. Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/2877 Signed-off-by: Chris Wilson Reviewed-by: Andi Shyti Link: https://patchwork.freedesktop.org/patch/msgid/20210104115145.24460-4-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/gt/intel_execlists_submission.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c index f02e3ae10d28..a5b442683c18 100644 --- a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c +++ b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c @@ -1016,6 +1016,9 @@ static bool virtual_matches(const struct virtual_engine *ve, { const struct intel_engine_cs *inflight; + if (!rq) + return false; + if (!(rq->execution_mask & engine->mask)) /* We peeked too soon! */ return false; @@ -1423,8 +1426,8 @@ check_secondary: spin_lock(&ve->base.active.lock); rq = ve->request; - if (unlikely(!rq)) /* lost the race to a sibling */ - goto unlock; + if (unlikely(!virtual_matches(ve, rq, engine))) + goto unlock; /* lost the race to a sibling */ GEM_BUG_ON(rq->engine != &ve->base); GEM_BUG_ON(rq->context != &ve->context); @@ -1434,8 +1437,6 @@ check_secondary: break; } - GEM_BUG_ON(!virtual_matches(ve, rq, engine)); - if (last && !can_merge_rq(last, rq)) { spin_unlock(&ve->base.active.lock); spin_unlock(&engine->active.lock);