FAILED: patch "[PATCH] drm/vc4: Shut down BO cache timer before teardown" failed to apply to 5.10-stable tree

The patch below does not apply to the 5.10-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x 6273dd3ffb54ec581855b82ae77331b66028249c
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026072903-limpness-utopia-a541@gregkh' --subject-prefix 'PATCH 5.10.y' 'HEAD^..'

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 6273dd3ffb54ec581855b82ae77331b66028249c Mon Sep 17 00:00:00 2001
From: Linmao Li <[email protected]>
Date: Mon, 20 Jul 2026 16:44:26 +0800
Subject: [PATCH] drm/vc4: Shut down BO cache timer before teardown
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The BO cache timer callback schedules time_work, and time_work can rearm the timer through vc4_bo_cache_free_old().

vc4_bo_cache_destroy() deletes the timer and then cancels the work, which does not break that cycle: the work being cancelled can rearm the timer, and the timer then queues work again after teardown.

Use timer_shutdown_sync() instead, so the timer cannot be rearmed and the cycle ends with cancel_work_sync().

index 5e7c46dd7823..49ea2ed0996b 100644
@@ -1048,7 +1048,7 @@ static void vc4_bo_cache_destroy(struct drm_device *dev, void *unused)
 	struct vc4_dev *vc4 = to_vc4_dev(dev);
 	int i;
 
-	timer_delete(&vc4->bo_cache.time_timer);
+	timer_shutdown_sync(&vc4->bo_cache.time_timer);
 	cancel_work_sync(&vc4->bo_cache.time_work);
 
 	vc4_bo_cache_purge(dev);