[v2,4/4] drm/amdgpu/dm/dp_mst: Don't grab mst_mgr->lock when computing DSC state
Commit Message
Now that we've fixed the issue with using the incorrect topology manager,
we're actually grabbing the topology manager's lock - and consequently
deadlocking. Luckily for us though, there's actually nothing in AMD's DSC
state computation code that really should need this lock. The one exception
is the mutex_lock() in dm_dp_mst_is_port_support_mode(), however we grab no
locks beneath &mgr->lock there so that should be fine to leave be.
Signed-off-by: Lyude Paul <lyude@redhat.com>
Gitlab issue: https://gitlab.freedesktop.org/drm/amd/-/issues/2171
Fixes: 8c20a1ed9b4f ("drm/amd/display: MST DSC compute fair share")
Cc: <stable@vger.kernel.org> # v5.6+
---
drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c | 4 ----
1 file changed, 4 deletions(-)
@@ -1148,10 +1148,8 @@ int compute_mst_dsc_configs_for_state(struct drm_atomic_state *state,
continue;
mst_mgr = aconnector->port->mgr;
- mutex_lock(&mst_mgr->lock);
ret = compute_mst_dsc_configs_for_link(state, dc_state, stream->link, vars, mst_mgr,
&link_vars_start_index);
- mutex_unlock(&mst_mgr->lock);
if (ret != 0)
return ret;
@@ -1208,10 +1206,8 @@ static int pre_compute_mst_dsc_configs_for_state(struct drm_atomic_state *state,
continue;
mst_mgr = aconnector->port->mgr;
- mutex_lock(&mst_mgr->lock);
ret = compute_mst_dsc_configs_for_link(state, dc_state, stream->link, vars, mst_mgr,
&link_vars_start_index);
- mutex_unlock(&mst_mgr->lock);
if (ret != 0)
return ret;