[Intel-gfx] [PATCH] drm/i915: Kick rcu harder to free objects

[Ville Syrjala]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

On gen3 the selftests are pretty much always tripping this:
<4> [383.822424] pci 0000:00:02.0: drm_WARN_ON(dev_priv->mm.shrink_count)
<4> [383.822546] WARNING: CPU: 2 PID: 3560 at drivers/gpu/drm/i915/i915_gem.c:1223 i915_gem_cleanup_early+0x96/0xb0 [i915]

Looks to be due to the status page object lingering on the
purge_list. Call synchronize_rcu() ahead of it to make more
sure all objects have been freed.

Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/i915_gem.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 0f49ec9d494a..5b61f7ad6473 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -1098,6 +1098,7 @@ void i915_gem_drain_freed_objects(struct drm_i915_private *i915)
 		flush_delayed_work(&i915->bdev.wq);
 		rcu_barrier();
 	}
+	synchronize_rcu();
 }
 
 /*
-- 
2.35.1