drm/radeon: Fix a missing check bug in radeon_dp_mst_detect()

[ Upstream commit 25315ebfaefcffd126a266116b37bb8a3d1c4620 ]

In radeon_dp_mst_detect(), We should check whether or not @connector
has been unregistered from userspace. If the connector is unregistered,
we should return disconnected status.

Fixes: 9843ead08f18 ("drm/radeon: add DisplayPort MST support (v2)")
Signed-off-by: Yingjie Wang <wangyingjie55@126.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/gpu/drm/radeon/radeon_dp_mst.c b/drivers/gpu/drm/radeon/radeon_dp_mst.c
index 0083087..9bd6c06 100644 (file)
--- a/drivers/gpu/drm/radeon/radeon_dp_mst.c
+++ b/drivers/gpu/drm/radeon/radeon_dp_mst.c
@@ -242,6 +242,9 @@ radeon_dp_mst_detect(struct drm_connector *connector,
                to_radeon_connector(connector);
        struct radeon_connector *master = radeon_connector->mst_port;
 
+       if (drm_connector_is_unregistered(connector))
+               return connector_status_disconnected;
+
        return drm_dp_mst_detect_port(connector, ctx, &master->mst_mgr,
                                      radeon_connector->port);
 }