From ce271b40a91f781af3dee985c39e841ac5148766 Mon Sep 17 00:00:00 2001 From: Qingqing Zhuo Date: Thu, 30 Jul 2020 15:35:41 -0400 Subject: [PATCH] drm/amd/display: Screen corruption on dual displays (DP+USB-C) [why] Current pipe merge and split logic only supports cases where new dc_state is allocated and relies on dc->current_state to gather information from previous dc_state. Calls to validate_bandwidth on UPDATE_TYPE_MED would cause an issue because there is no new dc_state allocated, and data in dc->current_state would be overwritten during pipe merge. [how] Only allow validate_bandwidth when new dc_state space is created. Signed-off-by: Qingqing Zhuo Reviewed-by: Nicholas Kazlauskas Acked-by: Rodrigo Siqueira Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/display/dc/core/dc.c | 2 +- drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c | 3 +++ drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c | 3 +++ 3 files changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c b/drivers/gpu/drm/amd/display/dc/core/dc.c index a2084f279e7b..dc463d99ef50 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc.c @@ -2636,7 +2636,7 @@ void dc_commit_updates_for_stream(struct dc *dc, copy_stream_update_to_stream(dc, context, stream, stream_update); - if (update_type > UPDATE_TYPE_FAST) { + if (update_type >= UPDATE_TYPE_FULL) { if (!dc->res_pool->funcs->validate_bandwidth(dc, context, false)) { DC_ERROR("Mode validation failed for stream update!\n"); dc_release_state(context); diff --git a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c index c31d1f30e505..1b9874445134 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c +++ b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c @@ -3209,6 +3209,9 @@ static noinline bool dcn20_validate_bandwidth_fp(struct dc *dc, context->bw_ctx.dml.soc.allow_dram_clock_one_display_vactive = dc->debug.enable_dram_clock_change_one_display_vactive; + /*Unsafe due to current pipe merge and split logic*/ + ASSERT(context != dc->current_state); + if (fast_validate) { return dcn20_validate_bandwidth_internal(dc, context, true); } diff --git a/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c b/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c index a828696668bf..78743ae37851 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c +++ b/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c @@ -1184,6 +1184,9 @@ bool dcn21_validate_bandwidth(struct dc *dc, struct dc_state *context, BW_VAL_TRACE_COUNT(); + /*Unsafe due to current pipe merge and split logic*/ + ASSERT(context != dc->current_state); + out = dcn20_fast_validate_bw(dc, context, pipes, &pipe_cnt, pipe_split_from, &vlevel); if (pipe_cnt == 0)