This is a note to let you know that I've just added the patch titled
drm/radeon: delete radeon_fence_process in is_signaled, no deadlock
to the 6.6-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-radeon-delete-radeon_fence_process-in-is_signaled-no-deadlock.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.
>From [email protected] Mon Feb 2 08:58:36 2026
From: Li hongliang <[email protected]>
Date: Mon, 2 Feb 2026 15:58:31 +0800
Subject: drm/radeon: delete radeon_fence_process in is_signaled, no deadlock
To: [email protected], [email protected], [email protected]
Cc: [email protected], [email protected],
[email protected], [email protected], [email protected],
[email protected], [email protected], [email protected],
[email protected]
Message-ID: <[email protected]>
From: Robert McClinton <[email protected]>
[ Upstream commit 9eb00b5f5697bd56baa3222c7a1426fa15bacfb5 ]
Delete the attempt to progress the queue when checking if fence is
signaled. This avoids deadlock.
dma-fence_ops::signaled can be called with the fence lock in unknown
state. For radeon, the fence lock is also the wait queue lock. This can
cause a self deadlock when signaled() tries to make forward progress on
the wait queue. But advancing the queue is unneeded because incorrectly
returning false from signaled() is perfectly acceptable.
Link: https://github.com/brave/brave-browser/issues/49182
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4641
Cc: Alex Deucher <[email protected]>
Signed-off-by: Robert McClinton <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
(cherry picked from commit 527ba26e50ec2ca2be9c7c82f3ad42998a75d0db)
Cc: [email protected]
[ Minor conflict resolved. ]
Signed-off-by: Li hongliang <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
drivers/gpu/drm/radeon/radeon_fence.c | 8 --------
1 file changed, 8 deletions(-)
--- a/drivers/gpu/drm/radeon/radeon_fence.c
+++ b/drivers/gpu/drm/radeon/radeon_fence.c
@@ -362,14 +362,6 @@ static bool radeon_fence_is_signaled(str
return true;
}
- if (down_read_trylock(&rdev->exclusive_lock)) {
- radeon_fence_process(rdev, ring);
- up_read(&rdev->exclusive_lock);
-
- if (atomic64_read(&rdev->fence_drv[ring].last_seq) >= seq) {
- return true;
- }
- }
return false;
}
Patches currently in stable-queue which might be from [email protected] are
queue-6.6/drm-radeon-delete-radeon_fence_process-in-is_signaled-no-deadlock.patch
queue-6.6/ksmbd-fix-race-condition-in-rpc-handle-list-access.patch
queue-6.6/wifi-ath11k-add-srng-lock-for-ath11k_hal_srng_-in-monitor-mode.patch
queue-6.6/drm-amdgpu-replace-mutex-with-spinlock-for-rlcg-register-access-to-avoid-priority-inversion-in-sriov.patch
