[Intel-gfx] [PATCH] drm/i915/display: Warn if the FBC is still writing to stolen on removal

[Chris Wilson]

If the FBC is still writing into stolen, it will overwrite any future
users of that stolen region. Check before release.

References: https://gitlab.freedesktop.org/drm/intel/-/issues/1635
Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/display/intel_fbc.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c b/drivers/gpu/drm/i915/display/intel_fbc.c
index c6afa10e814c..37244ed92ae4 100644
--- a/drivers/gpu/drm/i915/display/intel_fbc.c
+++ b/drivers/gpu/drm/i915/display/intel_fbc.c
@@ -540,6 +540,9 @@ static void __intel_fbc_cleanup_cfb(struct drm_i915_private *dev_priv)
 {
 	struct intel_fbc *fbc = &dev_priv->fbc;
 
+	if (WARN_ON(intel_fbc_hw_is_active(dev_priv)))
+		return;
+
 	if (!drm_mm_node_allocated(&fbc->compressed_fb))
 		return;
 
-- 
2.20.1