Since commit a481daa88fd4 ("drm/radeon: always apply pci shutdown
callbacks"), a Dell Latitude D600 laptop has crashed on shutdown. The
PCI Identification of the graphics adapter is "VGA compatible controller
[0300]: Advanced Micro Devices, Inc. [AMD/ATI] RV250/M9 GL [Mobility
FireGL 9000/Radeon 9000] [1002:4c66] (rev 01)".
Prior to commit b0c80bd5d2e3 ("drm/radeon: fix up dp aux tear down (v2)"),
I have no idea where the panic happened as the screen was blanked before
the crash. Since that more recent change, the panic has been in routine
radeon_connector_unregister(), and has been shown to be due to a NULL
value in the ddc_bus member of struct drm_connector.
Fixes: a481daa88fd4 ("drm/radeon: always apply pci shutdown callbacks")
Signed-off-by: Larry Finger <larry.fin...@lwfinger.net>
Cc: Alex Deucher <alexander.deuc...@amd.com>
---
drivers/gpu/drm/radeon/radeon_connectors.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/radeon/radeon_connectors.c
b/drivers/gpu/drm/radeon/radeon_connectors.c
index e18839d..27affbd 100644
--- a/drivers/gpu/drm/radeon/radeon_connectors.c
+++ b/drivers/gpu/drm/radeon/radeon_connectors.c
@@ -931,7 +931,7 @@ static void radeon_connector_unregister(struct
drm_connector *connector)
{
struct radeon_connector *radeon_connector =
to_radeon_connector(connector);
- if (radeon_connector->ddc_bus->has_aux) {
+ if (radeon_connector->ddc_bus && radeon_connector->ddc_bus->has_aux) {
drm_dp_aux_unregister(&radeon_connector->ddc_bus->aux);
radeon_connector->ddc_bus->has_aux = false;
}
--
2.10.0
