From: Natanel Roizenman natanel.roizenman@amd.com

[WHY] When switching from "Extend" to "Second Display Only" we sometimes call resource_get_otg_master_for_stream on a stream for the eDP, which is disconnected. This leads to a null pointer dereference.

[HOW] Added a null check in dc_resource.c/resource_log_pipe_topology_update.

CC: stable@vger.kernel.org Reviewed-by: Nicholas Kazlauskas nicholas.kazlauskas@amd.com Acked-by: Aurabindo Pillai aurabindo.pillai@amd.com Signed-off-by: Natanel Roizenman natanel.roizenman@amd.com Tested-by: Daniel Wheeler daniel.wheeler@amd.com --- drivers/gpu/drm/amd/display/dc/core/dc_resource.c | 4 ++++ 1 file changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c index c6c30919cdd1..77c9c3ee755d 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c @@ -2295,6 +2295,10 @@ void resource_log_pipe_topology_update(struct dc *dc, struct dc_state *state)

otg_master = resource_get_otg_master_for_stream( &state->res_ctx, state->streams[stream_idx]); + + if (!otg_master) + continue; + resource_log_pipe_for_stream(dc, state, otg_master, stream_idx); } if (state->phantom_stream_count > 0) {