drm/i915: GEM operations need to be done under the big lock
VMA creation and GEM list management need the big lock.
v2:
Mutex unlock ended on the wrong path somehow. (0-day, Julia Lawall)
Not to mention drm_gem_object_unreference was there in existing
code with no mutex held.
v3:
Some callers of i915_gem_object_create_stolen_for_preallocated
already hold the lock so move the mutex into the other caller
as well.
v4:
Changed to lockdep_assert_held. (Chris Wilson)
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index a18bd12..0811dd1 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -2551,12 +2551,16 @@
if (size_aligned * 2 > dev_priv->gtt.stolen_usable_size)
return false;
+ mutex_lock(&dev->struct_mutex);
+
obj = i915_gem_object_create_stolen_for_preallocated(dev,
base_aligned,
base_aligned,
size_aligned);
- if (!obj)
+ if (!obj) {
+ mutex_unlock(&dev->struct_mutex);
return false;
+ }
obj->tiling_mode = plane_config->tiling;
if (obj->tiling_mode == I915_TILING_X)
@@ -2569,12 +2573,12 @@
mode_cmd.modifier[0] = fb->modifier[0];
mode_cmd.flags = DRM_MODE_FB_MODIFIERS;
- mutex_lock(&dev->struct_mutex);
if (intel_framebuffer_init(dev, to_intel_framebuffer(fb),
&mode_cmd, obj)) {
DRM_DEBUG_KMS("intel fb init failed\n");
goto out_unref_obj;
}
+
mutex_unlock(&dev->struct_mutex);
DRM_DEBUG_KMS("initial plane fb obj %p\n", obj);