6.6-stable review patch. If anyone has any objections, please let me know.
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From: Joshua Aberback joshua.aberback@amd.com
[ Upstream commit 3a7810c212bcf2f722671dadf4b23ff70a7d23ee ]
[Why] It's possible to generate more than 50 steps in hwss_build_fast_sequence, for example with a 6-pipe asic where all pipes are in one MPC chain. This overflows the block_sequence buffer and corrupts block_sequence_steps, causing a crash.
[How] Expand block_sequence to 100 items. A naive upper bound on the possible number of steps for a 6-pipe asic, ignoring the potential for steps to be mutually exclusive, is 91 with current code, therefore 100 is sufficient.
Reviewed-by: Alvin Lee alvin.lee2@amd.com Signed-off-by: Joshua Aberback joshua.aberback@amd.com Signed-off-by: Wayne Lin wayne.lin@amd.com Tested-by: Daniel Wheeler daniel.wheeler@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/amd/display/dc/inc/core_types.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/display/dc/inc/core_types.h b/drivers/gpu/drm/amd/display/dc/inc/core_types.h index eaad1260bfd18..4b284ce669ae5 100644 --- a/drivers/gpu/drm/amd/display/dc/inc/core_types.h +++ b/drivers/gpu/drm/amd/display/dc/inc/core_types.h @@ -532,7 +532,7 @@ struct dc_state { */ struct bw_context bw_ctx;
- struct block_sequence block_sequence[50]; + struct block_sequence block_sequence[100]; unsigned int block_sequence_steps; struct dc_dmub_cmd dc_dmub_cmd[10]; unsigned int dmub_cmd_count;