This is a note to let you know that I've just added the patch titled drm/amd/display: check TG is non-null before checking if enabled to the 4.19-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-amd-display-check-tg-is-non-null-before-checking.patch and it can be found in the queue-4.19 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 765c875034bda06d832e76c72d48332e15f8ced3 Author: Taimur Hassan <syed.hassan@xxxxxxx> Date: Tue Jun 20 17:00:28 2023 -0400 drm/amd/display: check TG is non-null before checking if enabled [ Upstream commit 5a25cefc0920088bb9afafeb80ad3dcd84fe278b ] [Why & How] If there is no TG allocation we can dereference a NULL pointer when checking if the TG is enabled. Cc: Mario Limonciello <mario.limonciello@xxxxxxx> Cc: Alex Deucher <alexander.deucher@xxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@xxxxxxx> Acked-by: Alan Liu <haoping.liu@xxxxxxx> Signed-off-by: Taimur Hassan <syed.hassan@xxxxxxx> Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c index fc75337aa0a7f..ddec675ba690a 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c +++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c @@ -2529,7 +2529,8 @@ static void dcn10_wait_for_mpcc_disconnect( if (pipe_ctx->stream_res.opp->mpcc_disconnect_pending[mpcc_inst]) { struct hubp *hubp = get_hubp_by_inst(res_pool, mpcc_inst); - if (pipe_ctx->stream_res.tg->funcs->is_tg_enabled(pipe_ctx->stream_res.tg)) + if (pipe_ctx->stream_res.tg && + pipe_ctx->stream_res.tg->funcs->is_tg_enabled(pipe_ctx->stream_res.tg)) res_pool->mpc->funcs->wait_for_idle(res_pool->mpc, mpcc_inst); pipe_ctx->stream_res.opp->mpcc_disconnect_pending[mpcc_inst] = false; hubp->funcs->set_blank(hubp, true);