[Intel-gfx] [PATCH] drm/i915/gem: Silence sparse for RCU protection inside the constructor

[Chris Wilson]

Inside the constructor, while cloning, we need to replace the
dst->engines. Having forgotten that dst->engines is marked as RCU
protected, we need to add the appropriate annotations to make sparse
happy.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
---
 drivers/gpu/drm/i915/gem/i915_gem_context.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c b/drivers/gpu/drm/i915/gem/i915_gem_context.c
index 774d71b1ea9b..e8f4c5343e7b 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c
@@ -1987,7 +1987,8 @@ static int clone_engines(struct i915_gem_context *dst,
 	user_engines = i915_gem_context_user_engines(src);
 	i915_gem_context_unlock_engines(src);
 
-	free_engines(dst->engines);
+	/* Serialised by constructor */
+	free_engines(__context_engines_static(dst));
 	RCU_INIT_POINTER(dst->engines, clone);
 	if (user_engines)
 		i915_gem_context_set_user_engines(dst);
@@ -2022,7 +2023,8 @@ static int clone_sseu(struct i915_gem_context *dst,
 	unsigned long n;
 	int err;
 
-	clone = dst->engines; /* no locking required; sole access */
+	/* no locking required; sole access under constructor*/
+	clone = __context_engines_static(dst);
 	if (e->num_engines != clone->num_engines) {
 		err = -EINVAL;
 		goto unlock;
-- 
2.24.0