I've been experiencing some intermittent crashes down in the display driver code. The symptoms are ususally a line like this in dmesg: amdgpu 0000:30:00.0: [drm] Failed to create MST payload for port 000000006d3a3885: -5 ...followed by an Oops due to a NULL pointer dereference. Switch to using mgr->dev instead of state->dev since "state" can be NULL in some cases. Link: https://bugzilla.redhat.com/show_bug.cgi?id=2184855 Suggested-by: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx> Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx> --- drivers/gpu/drm/display/drm_dp_mst_topology.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) I've been running this patch for a couple of days, but the problem hasn't occurred again as of yet. It seems sane though as long as we can assume that mgr->dev will be valid even when "state" is a NULL pointer. diff --git a/drivers/gpu/drm/display/drm_dp_mst_topology.c b/drivers/gpu/drm/display/drm_dp_mst_topology.c index 38dab76ae69e..e2e21ce79510 100644 --- a/drivers/gpu/drm/display/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/display/drm_dp_mst_topology.c @@ -3404,7 +3404,7 @@ int drm_dp_add_payload_part2(struct drm_dp_mst_topology_mgr *mgr, /* Skip failed payloads */ if (payload->vc_start_slot == -1) { - drm_dbg_kms(state->dev, "Part 1 of payload creation for %s failed, skipping part 2\n", + drm_dbg_kms(mgr->dev, "Part 1 of payload creation for %s failed, skipping part 2\n", payload->port->connector->name); return -EIO; } -- 2.39.2