[Intel-gfx] [PATCH 3/6] drm/i915: Don't deref NULL crtc in intel_get_pipe_from_connector()

[ville.syrjala at linux.intel.com]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

If the connector would have an encoder but the encoder didn't have a
crtc we might dereference a NULL crtc here. I suppose that should never
happen due to intel_sanitize_encoder(), but let's be a bit paranoid
print a warning if we ever hit this and return INVALID_PIPE to the
caller.

Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/intel_display.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 9ec1ab7..b9529d0 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -12074,7 +12074,7 @@ enum pipe intel_get_pipe_from_connector(struct intel_connector *connector)
 
 	WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
 
-	if (!encoder)
+	if (!encoder || WARN_ON(!encoder->crtc))
 		return INVALID_PIPE;
 
 	return to_intel_crtc(encoder->crtc)->pipe;
-- 
2.0.4