From: Nicholas Kazlauskas nicholas.kazlauskas@amd.com
[ Upstream commit f04bee34d6e35df26cbb2d65e801adfd0d8fe20d ]
[Why] Unlike our regular connectors, MST connectors don't start off with an initial connector state. This causes a NULL pointer dereference to occur when attaching the bpc property since it tries to modify the connector state.
We need an initial connector state on the connector to avoid the crash.
[How] Use our reset helper to allocate an initial state and reset the values to their defaults. We were already doing this before, just not for MST connectors.
Signed-off-by: Nicholas Kazlauskas nicholas.kazlauskas@amd.com Reviewed-by: Leo Li sunpeng.li@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c index dac7978f5ee1..221de241535a 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -3644,6 +3644,13 @@ void amdgpu_dm_connector_init_helper(struct amdgpu_display_manager *dm, { struct amdgpu_device *adev = dm->ddev->dev_private;
+ /* + * Some of the properties below require access to state, like bpc. + * Allocate some default initial connector state with our reset helper. + */ + if (aconnector->base.funcs->reset) + aconnector->base.funcs->reset(&aconnector->base); + aconnector->connector_id = link_index; aconnector->dc_link = link; aconnector->base.interlace_allowed = false; @@ -3811,9 +3818,6 @@ static int amdgpu_dm_connector_init(struct amdgpu_display_manager *dm, &aconnector->base, &amdgpu_dm_connector_helper_funcs);
- if (aconnector->base.funcs->reset) - aconnector->base.funcs->reset(&aconnector->base); - amdgpu_dm_connector_init_helper( dm, aconnector,