From: hersen wu <hersenxs.wu@xxxxxxx>
[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 <Wayne.Lin@xxxxxxx>
Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira@xxxxxxx>
Acked-by: Hamza Mahfooz <hamza.mahfooz@xxxxxxx>
Signed-off-by: hersen wu <hersenxs.wu@xxxxxxx>
---
.../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
