From: Wayne Lin <wayne....@amd.com>
[ Upstream commit fcf6a49d79923a234844b8efe830a61f3f0584e4 ]
[Why]
When unplug one of monitors connected after mst hub, encounter null pointer
dereference.
It's due to dc_sink get released immediately in early_unregister() or
detect_ctx(). When
commit new state which directly referring to info stored in dc_sink will cause
null pointer
dereference.
[how]
Remove redundant checking condition. Relevant condition should already be
covered by checking
if dsc_aux is null or not. Also reset dsc_aux to NULL when the connector is
disconnected.
Reviewed-by: Jerry Zuo <jerry....@amd.com>
Acked-by: Zaeem Mohamed <zaeem.moha...@amd.com>
Signed-off-by: Wayne Lin <wayne....@amd.com>
Tested-by: Daniel Wheeler <daniel.whee...@amd.com>
Signed-off-by: Alex Deucher <alexander.deuc...@amd.com>
Signed-off-by: Jianqi Ren <jianqi.ren...@windriver.com>
---
drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
index 1acef5f3838f..a1619f4569cf 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
@@ -183,6 +183,8 @@ amdgpu_dm_mst_connector_early_unregister(struct
drm_connector *connector)
dc_sink_release(dc_sink);
aconnector->dc_sink = NULL;
aconnector->edid = NULL;
+ aconnector->dsc_aux = NULL;
+ port->passthrough_aux = NULL;
}
aconnector->mst_status = MST_STATUS_DEFAULT;
@@ -487,6 +489,8 @@ dm_dp_mst_detect(struct drm_connector *connector,
dc_sink_release(aconnector->dc_sink);
aconnector->dc_sink = NULL;
aconnector->edid = NULL;
+ aconnector->dsc_aux = NULL;
+ port->passthrough_aux = NULL;
amdgpu_dm_set_mst_status(&aconnector->mst_status,
MST_REMOTE_EDID | MST_ALLOCATE_NEW_PAYLOAD |
MST_CLEAR_ALLOCATED_PAYLOAD,
--
2.25.1
