The patch below does not apply to the 6.1-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 stable@vger.kernel.org.
Possible dependencies:
1cec34442408 ("drm/i915/gem: Flush contexts on driver release")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 1cec34442408a77ba5396b19725fed2c398005c3 Mon Sep 17 00:00:00 2001 From: Janusz Krzysztofik janusz.krzysztofik@linux.intel.com Date: Fri, 16 Sep 2022 11:24:02 +0200 Subject: [PATCH] drm/i915/gem: Flush contexts on driver release
Due to i915_perf assuming that it can use the i915_gem_context reference to protect its i915->gem.contexts.list iteration, we need to defer removal of the context from the list until last reference to the context is put. However, there is a risk of triggering kernel warning on contexts list not empty at driver release time if we deleagate that task to a worker for i915_gem_context_release_work(), unless that work is flushed first. Unfortunately, it is not flushed on driver release. Fix it.
Instead of additionally calling flush_workqueue(), either directly or via a new dedicated wrapper around it, replace last call to i915_gem_drain_freed_objects() with existing i915_gem_drain_workqueue() that performs both tasks.
Fixes: 75eefd82581f ("drm/i915: Release i915_gem_context from a worker") Suggested-by: Chris Wilson chris@chris-wilson.co.uk Signed-off-by: Janusz Krzysztofik janusz.krzysztofik@linux.intel.com Reviewed-by: Andi Shyti andi.shyti@linux.intel.com Cc: stable@kernel.org # v5.16+ Signed-off-by: Andi Shyti andi.shyti@linux.intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20220916092403.201355-2-janusz...
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index be7fede6cd6f..4539431a3c3e 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -1214,7 +1214,8 @@ void i915_gem_driver_release(struct drm_i915_private *dev_priv) intel_uc_cleanup_firmwares(>->uc); }
- i915_gem_drain_freed_objects(dev_priv); + /* Flush any outstanding work, including i915_gem_context.release_work. */ + i915_gem_drain_workqueue(dev_priv);
drm_WARN_ON(&dev_priv->drm, !list_empty(&dev_priv->gem.contexts.list)); }