6.1-stable review patch. If anyone has any objections, please let me know.
------------------
From: Srinivasan Shanmugam srinivasan.shanmugam@amd.com
commit 15c2990e0f0108b9c3752d7072a97d45d4283aea upstream.
This commit adds null checks for the 'stream' and 'plane' variables in the dcn30_apply_idle_power_optimizations function. These variables were previously assumed to be null at line 922, but they were used later in the code without checking if they were null. This could potentially lead to a null pointer dereference, which would cause a crash.
The null checks ensure that 'stream' and 'plane' are not null before they are used, preventing potential crashes.
Fixes the below static smatch checker: drivers/gpu/drm/amd/amdgpu/../display/dc/hwss/dcn30/dcn30_hwseq.c:938 dcn30_apply_idle_power_optimizations() error: we previously assumed 'stream' could be null (see line 922) drivers/gpu/drm/amd/amdgpu/../display/dc/hwss/dcn30/dcn30_hwseq.c:940 dcn30_apply_idle_power_optimizations() error: we previously assumed 'plane' could be null (see line 922)
Cc: Tom Chung chiahsuan.chung@amd.com Cc: Nicholas Kazlauskas nicholas.kazlauskas@amd.com Cc: Bhawanpreet Lakha Bhawanpreet.Lakha@amd.com Cc: Rodrigo Siqueira Rodrigo.Siqueira@amd.com Cc: Roman Li roman.li@amd.com Cc: Hersen Wu hersenxs.wu@amd.com Cc: Alex Hung alex.hung@amd.com Cc: Aurabindo Pillai aurabindo.pillai@amd.com Cc: Harry Wentland harry.wentland@amd.com Signed-off-by: Srinivasan Shanmugam srinivasan.shanmugam@amd.com Reviewed-by: Aurabindo Pillai aurabindo.pillai@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com [Xiangyu: Modified file path to backport this commit] Signed-off-by: Xiangyu Chen xiangyu.chen@windriver.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c | 3 +++ 1 file changed, 3 insertions(+)
--- a/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c +++ b/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c @@ -762,6 +762,9 @@ bool dcn30_apply_idle_power_optimization stream = dc->current_state->streams[0]; plane = (stream ? dc->current_state->stream_status[0].plane_states[0] : NULL);
+ if (!stream || !plane) + return false; + if (stream && plane) { cursor_cache_enable = stream->cursor_position.enable && plane->address.grph.cursor_cache_addr.quad_part;