From bbb21229ba0d94ac06822169cd024ebddd4ca06c Mon Sep 17 00:00:00 2001
From: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Date: Tue, 25 Jan 2022 12:04:34 -0500
Subject: drm/amd/display: Fix stream->link_enc unassigned during stream
removal
Git-commit: 3743e7f6fcb938b7d8b7967e6a9442805e269b3d
Patch-mainline: v5.17-rc6
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225
[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@amd.com>
Acked-by: Jasdeep Dhillon <jdhillon@amd.com>
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/amd/display/dc/core/dc_resource.c | 4 ----
1 file changed, 4 deletions(-)
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 b3912ff9dc91..18757c158523 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
@@ -1964,10 +1964,6 @@ 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(
--
2.38.1