aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorChris Wilson <[email protected]>2020-02-06 20:49:12 +0000
committerChris Wilson <[email protected]>2020-02-07 10:54:49 +0000
commitf91d8156ab8afb32447cd2bf3189219bab943f18 (patch)
tree16ee71aa63599516c423ba5b579b8017707b12f6
parent4f7e6d22b545225e27580aeed8a7519307fab7f5 (diff)
drm/i915/gt: Prevent queuing retire workers on the virtual engine
Virtual engines are fleeting. They carry a reference count and may be freed when their last request is retired. This makes them unsuitable for the task of housing engine->retire.work so assert that it is not used. Tvrtko tracked down an instance where we did indeed violate this rule. In virtual_submit_request, we flush a completed request directly with __i915_request_submit and this causes us to queue that request on the veng's breadcrumb list and signal it. Leading us down a path where we should not attach the retire. Reported-by: Tvrtko Ursulin <[email protected]> Fixes: dc93c9b69315 ("drm/i915/gt: Schedule request retirement when signaler idles") Signed-off-by: Chris Wilson <[email protected]> Cc: Tvrtko Ursulin <[email protected]> Reviewed-by: Mika Kuoppala <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]
-rw-r--r--drivers/gpu/drm/i915/gt/intel_breadcrumbs.c3
-rw-r--r--drivers/gpu/drm/i915/gt/intel_gt_requests.c3
2 files changed, 6 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c b/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c
index 0ba524a414c6..cbad7fe722ce 100644
--- a/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c
+++ b/drivers/gpu/drm/i915/gt/intel_breadcrumbs.c
@@ -136,6 +136,9 @@ static void add_retire(struct intel_breadcrumbs *b, struct intel_timeline *tl)
struct intel_engine_cs *engine =
container_of(b, struct intel_engine_cs, breadcrumbs);
+ if (unlikely(intel_engine_is_virtual(engine)))
+ engine = intel_virtual_engine_get_sibling(engine, 0);
+
intel_engine_add_retire(engine, tl);
}
diff --git a/drivers/gpu/drm/i915/gt/intel_gt_requests.c b/drivers/gpu/drm/i915/gt/intel_gt_requests.c
index 7ef1d37970f6..8a5054f21bf8 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt_requests.c
+++ b/drivers/gpu/drm/i915/gt/intel_gt_requests.c
@@ -99,6 +99,9 @@ static bool add_retire(struct intel_engine_cs *engine,
void intel_engine_add_retire(struct intel_engine_cs *engine,
struct intel_timeline *tl)
{
+ /* We don't deal well with the engine disappearing beneath us */
+ GEM_BUG_ON(intel_engine_is_virtual(engine));
+
if (add_retire(engine, tl))
schedule_work(&engine->retire_work);
}