From: hersen wu <[email protected]> [Why] when 4k@144hz dp connect to dp1.4 dsc mst hub, requested bandwidth exceeds caps of dsc hub. but dsc bw valid functions, increase_dsc_bpp, try_disable_dsc, pre_validate_dsc, compute_mst_dsc_configs_for_state, do not return false to atomic check. this cause user mode initiate mode set to kernel, then cause kernel assert, system hang.
[How] dsc bandwidth valid functions return pass or fail to atomic check. Reviewed-by: Wayne Lin <[email protected]> Reviewed-by: Rodrigo Siqueira <[email protected]> Acked-by: Hamza Mahfooz <[email protected]> Signed-off-by: hersen wu <[email protected]> --- .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 6 ++- .../display/amdgpu_dm/amdgpu_dm_mst_types.c | 43 +++++++++++++------ .../display/amdgpu_dm/amdgpu_dm_mst_types.h | 2 +- 3 files changed, 35 insertions(+), 16 deletions(-) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c index 06da4f2ed7ad..b048e40f23bf 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -11209,7 +11209,10 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev, } } } - pre_validate_dsc(state, &dm_state, vars); + if (!pre_validate_dsc(state, &dm_state, vars)) { + ret = -EINVAL; + goto fail; + } } #endif for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state, new_crtc_state, i) { @@ -11455,6 +11458,7 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev, #if defined(CONFIG_DRM_AMD_DC_DCN) if (!compute_mst_dsc_configs_for_state(state, dm_state->context, vars)) { DRM_DEBUG_DRIVER("compute_mst_dsc_configs_for_state() failed\n"); + ret = -EINVAL; goto fail; } diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c index 78df51b8693e..bdfe5a9a08dd 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c @@ -670,7 +670,7 @@ static int bpp_x16_from_pbn(struct dsc_mst_fairness_params param, int pbn) return dsc_config.bits_per_pixel; } -static void increase_dsc_bpp(struct drm_atomic_state *state, +static bool increase_dsc_bpp(struct drm_atomic_state *state, struct dc_link *dc_link, struct dsc_mst_fairness_params *params, struct dsc_mst_fairness_vars *vars, @@ -730,7 +730,7 @@ static void increase_dsc_bpp(struct drm_atomic_state *state, params[next_index].port, vars[next_index].pbn, pbn_per_timeslot) < 0) - return; + return false; if (!drm_dp_mst_atomic_check(state)) { vars[next_index].bpp_x16 = bpp_x16_from_pbn(params[next_index], vars[next_index].pbn); } else { @@ -740,7 +740,7 @@ static void increase_dsc_bpp(struct drm_atomic_state *state, params[next_index].port, vars[next_index].pbn, pbn_per_timeslot) < 0) - return; + return false; } } else { vars[next_index].pbn += initial_slack[next_index]; @@ -749,7 +749,7 @@ static void increase_dsc_bpp(struct drm_atomic_state *state, params[next_index].port, vars[next_index].pbn, pbn_per_timeslot) < 0) - return; + return false; if (!drm_dp_mst_atomic_check(state)) { vars[next_index].bpp_x16 = params[next_index].bw_range.max_target_bpp_x16; } else { @@ -759,16 +759,17 @@ static void increase_dsc_bpp(struct drm_atomic_state *state, params[next_index].port, vars[next_index].pbn, pbn_per_timeslot) < 0) - return; + return false; } } bpp_increased[next_index] = true; remaining_to_increase--; } + return true; } -static void try_disable_dsc(struct drm_atomic_state *state, +static bool try_disable_dsc(struct drm_atomic_state *state, struct dc_link *dc_link, struct dsc_mst_fairness_params *params, struct dsc_mst_fairness_vars *vars, @@ -816,7 +817,7 @@ static void try_disable_dsc(struct drm_atomic_state *state, params[next_index].port, vars[next_index].pbn, dm_mst_get_pbn_divider(dc_link)) < 0) - return; + return false; if (!drm_dp_mst_atomic_check(state)) { vars[next_index].dsc_enabled = false; @@ -828,12 +829,13 @@ static void try_disable_dsc(struct drm_atomic_state *state, params[next_index].port, vars[next_index].pbn, dm_mst_get_pbn_divider(dc_link)) < 0) - return; + return false; } tried[next_index] = true; remaining_to_try--; } + return true; } static bool compute_mst_dsc_configs_for_link(struct drm_atomic_state *state, @@ -949,9 +951,11 @@ static bool compute_mst_dsc_configs_for_link(struct drm_atomic_state *state, return false; /* Optimize degree of compression */ - increase_dsc_bpp(state, dc_link, params, vars, count, k); + if (!increase_dsc_bpp(state, dc_link, params, vars, count, k)) + return false; - try_disable_dsc(state, dc_link, params, vars, count, k); + if (!try_disable_dsc(state, dc_link, params, vars, count, k)) + return false; set_dsc_configs_from_fairness_vars(params, vars, count, k); @@ -1223,21 +1227,22 @@ static bool is_dsc_precompute_needed(struct drm_atomic_state *state) return ret; } -void pre_validate_dsc(struct drm_atomic_state *state, +bool pre_validate_dsc(struct drm_atomic_state *state, struct dm_atomic_state **dm_state_ptr, struct dsc_mst_fairness_vars *vars) { int i; struct dm_atomic_state *dm_state; struct dc_state *local_dc_state = NULL; + int ret = 0; if (!is_dsc_precompute_needed(state)) { DRM_INFO_ONCE("DSC precompute is not needed.\n"); - return; + return true; } if (dm_atomic_get_state(state, dm_state_ptr)) { DRM_INFO_ONCE("dm_atomic_get_state() failed\n"); - return; + return false; } dm_state = *dm_state_ptr; @@ -1249,7 +1254,7 @@ void pre_validate_dsc(struct drm_atomic_state *state, local_dc_state = kmemdup(dm_state->context, sizeof(struct dc_state), GFP_KERNEL); if (!local_dc_state) - return; + return false; for (i = 0; i < local_dc_state->stream_count; i++) { struct dc_stream_state *stream = dm_state->context->streams[i]; @@ -1275,11 +1280,19 @@ void pre_validate_dsc(struct drm_atomic_state *state, &state->crtcs[ind].new_state->mode, dm_new_conn_state, dm_old_crtc_state->stream); + if (local_dc_state->streams[i] == NULL) { + ret = -EINVAL; + break; + } } } + if (ret != 0) + goto clean_exit; + if (!pre_compute_mst_dsc_configs_for_state(state, local_dc_state, vars)) { DRM_INFO_ONCE("pre_compute_mst_dsc_configs_for_state() failed\n"); + ret = -EINVAL; goto clean_exit; } @@ -1309,5 +1322,7 @@ void pre_validate_dsc(struct drm_atomic_state *state, } kfree(local_dc_state); + + return (ret == 0); } #endif diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h index 85628ad59e6c..2e13027d9b88 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h @@ -59,7 +59,7 @@ bool compute_mst_dsc_configs_for_state(struct drm_atomic_state *state, bool needs_dsc_aux_workaround(struct dc_link *link); -void pre_validate_dsc(struct drm_atomic_state *state, +bool pre_validate_dsc(struct drm_atomic_state *state, struct dm_atomic_state **dm_state_ptr, struct dsc_mst_fairness_vars *vars); -- 2.36.1
