6.6-stable review patch. If anyone has any objections, please let me know.
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From: Srinivasan Shanmugam srinivasan.shanmugam@amd.com
[ Upstream commit e96fddb32931d007db12b1fce9b5e8e4c080401b ]
'panel_cntl' structure used to control the display panel could be null, dereferencing it could lead to a null pointer access.
Fixes the below: drivers/gpu/drm/amd/amdgpu/../display/dc/hwss/dcn21/dcn21_hwseq.c:269 dcn21_set_backlight_level() error: we previously assumed 'panel_cntl' could be null (see line 250)
Fixes: 474ac4a875ca ("drm/amd/display: Implement some asic specific abm call backs.") Cc: Yongqiang Sun yongqiang.sun@amd.com Cc: Anthony Koo Anthony.Koo@amd.com Cc: Rodrigo Siqueira Rodrigo.Siqueira@amd.com Cc: Aurabindo Pillai aurabindo.pillai@amd.com Signed-off-by: Srinivasan Shanmugam srinivasan.shanmugam@amd.com Reviewed-by: Anthony Koo Anthony.Koo@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- .../drm/amd/display/dc/dcn21/dcn21_hwseq.c | 39 ++++++++++--------- 1 file changed, 20 insertions(+), 19 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_hwseq.c b/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_hwseq.c index f99b1bc49694..7238930e6383 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_hwseq.c +++ b/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_hwseq.c @@ -237,34 +237,35 @@ bool dcn21_set_backlight_level(struct pipe_ctx *pipe_ctx, { struct dc_context *dc = pipe_ctx->stream->ctx; struct abm *abm = pipe_ctx->stream_res.abm; + struct timing_generator *tg = pipe_ctx->stream_res.tg; struct panel_cntl *panel_cntl = pipe_ctx->stream->link->panel_cntl; + uint32_t otg_inst; + + if (!abm && !tg && !panel_cntl) + return false; + + otg_inst = tg->inst;
if (dc->dc->res_pool->dmcu) { dce110_set_backlight_level(pipe_ctx, backlight_pwm_u16_16, frame_ramp); return true; }
- if (abm != NULL) { - uint32_t otg_inst = pipe_ctx->stream_res.tg->inst; - - if (abm && panel_cntl) { - if (abm->funcs && abm->funcs->set_pipe_ex) { - abm->funcs->set_pipe_ex(abm, - otg_inst, - SET_ABM_PIPE_NORMAL, - panel_cntl->inst, - panel_cntl->pwrseq_inst); - } else { - dmub_abm_set_pipe(abm, - otg_inst, - SET_ABM_PIPE_NORMAL, - panel_cntl->inst, - panel_cntl->pwrseq_inst); - } - } + if (abm->funcs && abm->funcs->set_pipe_ex) { + abm->funcs->set_pipe_ex(abm, + otg_inst, + SET_ABM_PIPE_NORMAL, + panel_cntl->inst, + panel_cntl->pwrseq_inst); + } else { + dmub_abm_set_pipe(abm, + otg_inst, + SET_ABM_PIPE_NORMAL, + panel_cntl->inst, + panel_cntl->pwrseq_inst); }
- if (abm && abm->funcs && abm->funcs->set_backlight_level_pwm) + if (abm->funcs && abm->funcs->set_backlight_level_pwm) abm->funcs->set_backlight_level_pwm(abm, backlight_pwm_u16_16, frame_ramp, 0, panel_cntl->inst); else