diff options
| author | Maarten Lankhorst <maarten.lankhorst@linux.intel.com> | 2015-08-11 10:54:29 +0300 |
|---|---|---|
| committer | Jani Nikula <jani.nikula@intel.com> | 2015-08-11 12:30:38 +0300 |
| commit | 4772ff03df8094fd99d28de5fcf5df3a3e9c68bb (patch) | |
| tree | 2a4d3df228d96c5aac622bdcf1a7289a08bcc5bb /drivers/gpu/drm/drm_dp_mst_topology.c | |
| parent | 5677d67ae3949f09f57357241b88222d49b8c782 (diff) | |
| download | linux-4772ff03df8094fd99d28de5fcf5df3a3e9c68bb.tar.xz | |
drm/dp/mst: Remove port after removing connector.
The port is removed synchronously, but the connector delayed.
This causes a use after free which can cause a kernel BUG with
slug_debug=FPZU. This is fixed by freeing the port after the
connector.
This fixes a regression introduced with
6b8eeca65b18ae77e175cc2b6571731f0ee413bf
"drm/dp/mst: close deadlock in connector destruction."
Cc: stable@vger.kernel.org
Cc: Dave Airlie <airlied@redhat.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Diffstat (limited to 'drivers/gpu/drm/drm_dp_mst_topology.c')
| -rw-r--r-- | drivers/gpu/drm/drm_dp_mst_topology.c | 19 |
1 files changed, 13 insertions, 6 deletions
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c index 778bbb6425b8..1325eecb0510 100644 --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -873,9 +873,10 @@ static void drm_dp_destroy_port(struct kref *kref) from an EDID retrieval */ if (port->connector) { mutex_lock(&mgr->destroy_connector_lock); - list_add(&port->connector->destroy_list, &mgr->destroy_connector_list); + list_add(&port->next, &mgr->destroy_connector_list); mutex_unlock(&mgr->destroy_connector_lock); schedule_work(&mgr->destroy_connector_work); + return; } drm_dp_port_teardown_pdt(port, port->pdt); @@ -2660,7 +2661,7 @@ static void drm_dp_tx_work(struct work_struct *work) static void drm_dp_destroy_connector_work(struct work_struct *work) { struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, destroy_connector_work); - struct drm_connector *connector; + struct drm_dp_mst_port *port; /* * Not a regular list traverse as we have to drop the destroy @@ -2669,15 +2670,21 @@ static void drm_dp_destroy_connector_work(struct work_struct *work) */ for (;;) { mutex_lock(&mgr->destroy_connector_lock); - connector = list_first_entry_or_null(&mgr->destroy_connector_list, struct drm_connector, destroy_list); - if (!connector) { + port = list_first_entry_or_null(&mgr->destroy_connector_list, struct drm_dp_mst_port, next); + if (!port) { mutex_unlock(&mgr->destroy_connector_lock); break; } - list_del(&connector->destroy_list); + list_del(&port->next); mutex_unlock(&mgr->destroy_connector_lock); - mgr->cbs->destroy_connector(mgr, connector); + mgr->cbs->destroy_connector(mgr, port->connector); + + drm_dp_port_teardown_pdt(port, port->pdt); + + if (!port->input && port->vcpi.vcpi > 0) + drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi); + kfree(port); } } |