This is a note to let you know that I've just added the patch titled
drm/i915/guc: Don't drop ce->guc_active.lock when unwinding context
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-don-t-drop-ce-guc_active.lock-when-unwinding-context.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 88209a8ecb8b8752322908a3c3362a001bdc3a39 Mon Sep 17 00:00:00 2001
From: Matthew Brost <matthew.brost@xxxxxxxxx>
Date: Thu, 9 Sep 2021 09:47:25 -0700
Subject: drm/i915/guc: Don't drop ce->guc_active.lock when unwinding context
From: Matthew Brost <matthew.brost@xxxxxxxxx>
commit 88209a8ecb8b8752322908a3c3362a001bdc3a39 upstream.
Don't drop ce->guc_active.lock when unwinding a context after reset.
At one point we had to drop this because of a lock inversion but that is
no longer the case. It is much safer to hold the lock so let's do that.
Fixes: eb5e7da736f3 ("drm/i915/guc: Reset implementation for new GuC interface")
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@xxxxxxxxx>
Signed-off-by: Matthew Brost <matthew.brost@xxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: John Harrison <John.C.Harrison@xxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-5-matthew.brost@xxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c | 4 ----
1 file changed, 4 deletions(-)
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
@@ -814,8 +814,6 @@ __unwind_incomplete_requests(struct inte
continue;
list_del_init(&rq->sched.link);
- spin_unlock(&ce->guc_active.lock);
-
__i915_request_unsubmit(rq);
/* Push the request back into the queue for later resubmission. */
@@ -828,8 +826,6 @@ __unwind_incomplete_requests(struct inte
list_add_tail(&rq->sched.link, pl);
set_bit(I915_FENCE_FLAG_PQUEUE, &rq->fence.flags);
-
- spin_lock(&ce->guc_active.lock);
}
spin_unlock(&ce->guc_active.lock);
spin_unlock_irqrestore(&sched_engine->lock, flags);
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
