drm/i915: Warn when releasing a frontbuffer while in use

Let's scream if we are about to release a frontbuffer which
is still in use.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210209021918.16234-3-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>

diff --git a/drivers/gpu/drm/i915/display/intel_frontbuffer.c b/drivers/gpu/drm/i915/display/intel_frontbuffer.c
index d898b37..b2744c5 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_frontbuffer.c
+++ b/drivers/gpu/drm/i915/display/intel_frontbuffer.c
@@ -224,6 +224,8 @@ static void frontbuffer_release(struct kref *ref)
        struct drm_i915_gem_object *obj = front->obj;
        struct i915_vma *vma;
 
+       drm_WARN_ON(obj->base.dev, atomic_read(&front->bits));
+
        spin_lock(&obj->vma.lock);
        for_each_ggtt_vma(vma, obj)
                vma->display_alignment = I915_GTT_MIN_ALIGNMENT;