[PATCH v1] drm/dp/mst: fix missing modeset unlock for MST port detect

From: Ramya SR
Date: Fri Sep 15 2023 - 00:55:35 EST


Modeset mutex unlock is missing in drm_dp_mst_detect_port function.
This will lead to deadlock if calling the function multiple times in
an atomic operation, for example, getting imultiple MST ports status
for a DP MST bonding scenario.

Signed-off-by: Ramya SR <quic_rsr@xxxxxxxxxxx>
---
drivers/gpu/drm/display/drm_dp_mst_topology.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/display/drm_dp_mst_topology.c b/drivers/gpu/drm/display/drm_dp_mst_topology.c
index ed96cfc..d6512c4 100644
--- a/drivers/gpu/drm/display/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/display/drm_dp_mst_topology.c
@@ -4154,7 +4154,7 @@ drm_dp_mst_detect_port(struct drm_connector *connector,

ret = drm_modeset_lock(&mgr->base.lock, ctx);
if (ret)
- goto out;
+ goto fail;

ret = connector_status_disconnected;

@@ -4181,6 +4181,8 @@ drm_dp_mst_detect_port(struct drm_connector *connector,
break;
}
out:
+ drm_modeset_unlock(&mgr->base.lock);
+fail:
drm_dp_mst_topology_put_port(port);
return ret;
}
--
2.7.4