From: Nicholas Kazlauskas <nicholas.kazlauskas@xxxxxxx> commit 3743e7f6fcb938b7d8b7967e6a9442805e269b3d upstream. [Why] Found when running igt@kms_atomic. Userspace attempts to do a TEST_COMMIT when 0 streams which calls dc_remove_stream_from_ctx. This in turn calls link_enc_unassign which ends up modifying stream->link = NULL directly, causing the global link_enc to be removed preventing further link activity and future link validation from passing. [How] We take care of link_enc unassignment at the start of link_enc_cfg_link_encs_assign so this call is no longer necessary. Fixes global state from being modified while unlocked. Reviewed-by: Jimmy Kizito <Jimmy.Kizito@xxxxxxx> Acked-by: Jasdeep Dhillon <jdhillon@xxxxxxx> Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@xxxxxxx> Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/amd/display/dc/core/dc_resource.c | 4 ---- 1 file changed, 4 deletions(-) --- a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c @@ -1876,10 +1876,6 @@ enum dc_status dc_remove_stream_from_ctx dc->res_pool, del_pipe->stream_res.stream_enc, false); - /* Release link encoder from stream in new dc_state. */ - if (dc->res_pool->funcs->link_enc_unassign) - dc->res_pool->funcs->link_enc_unassign(new_ctx, del_pipe->stream); - #if defined(CONFIG_DRM_AMD_DC_DCN) if (is_dp_128b_132b_signal(del_pipe)) { update_hpo_dp_stream_engine_usage( Patches currently in stable-queue which might be from nicholas.kazlauskas@xxxxxxx are queue-5.16/drm-amd-display-fix-stream-link_enc-unassigned-during-stream-removal.patch