From add0e494245ea62c6ba86b1bda44cf5fb6784e41 Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Fri, 13 Dec 2019 22:31:40 +0000
Subject: drm/i915/gem: Serialise object before changing cache-level
Git-commit: 7a90f89904afe66ff029bd784679aa293baacb72
Patch-mainline: v5.6-rc1
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322
Wait for the object to be idle before changing its cache-level and
unbinding. This was dropped as supposedly superfluous from commit
8b1c78e06e61 ("drm/i915: Avoid calling i915_gem_object_unbind holding
object lock"), but it turns out to prevent some cache dirt escaping.
Smells like papering over a race...
Closes: https://gitlab.freedesktop.org/drm/intel/issues/820
Fixes: 8b1c78e06e61 ("drm/i915: Avoid calling i915_gem_object_unbind holding object lock")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Andi Shyti <andi.shyti@intel.com>
Acked-by: Andi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191213223140.1830738-1-chris@chris-wilson.co.uk
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/i915/gem/i915_gem_domain.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_domain.c b/drivers/gpu/drm/i915/gem/i915_gem_domain.c
index 0fa3c6325ff4..0cc40e77bbd2 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_domain.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_domain.c
@@ -190,6 +190,13 @@ int i915_gem_object_set_cache_level(struct drm_i915_gem_object *obj,
if (obj->cache_level == cache_level)
return 0;
+ ret = i915_gem_object_wait(obj,
+ I915_WAIT_INTERRUPTIBLE |
+ I915_WAIT_ALL,
+ MAX_SCHEDULE_TIMEOUT);
+ if (ret)
+ return ret;
+
ret = i915_gem_object_lock_interruptible(obj);
if (ret)
return ret;
--
2.28.0