[PATCH AUTOSEL 6.11 132/244] drm/amd/display: Check null pointers before used

Sasha Levin
2024-09-25T11:43:55Z

From: Alex Hung <alex.hung@amd.com>

[ Upstream commit be1fb44389ca3038ad2430dac4234669bc177ee3 ]

[WHAT & HOW]
Poniters, such as dc->clk_mgr, are null checked previously in the same
function, so Coverity warns "implies that "dc->clk_mgr" might be null".
As a result, these pointers need to be checked when used again.

This fixes 10 FORWARD_NULL issues reported by Coverity.

Reviewed-by: Rodrigo Siqueira <rodrigo.siqueira@amd.com>
Signed-off-by: Jerry Zuo <jerry.zuo@amd.com>
Signed-off-by: Alex Hung <alex.hung@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>
---
.../drm/amd/display/dc/clk_mgr/dce110/dce110_clk_mgr.c | 2 +-
drivers/gpu/drm/amd/display/dc/hubp/dcn10/dcn10_hubp.c | 3 ++-
drivers/gpu/drm/amd/display/dc/hubp/dcn20/dcn20_hubp.c | 3 ++-
drivers/gpu/drm/amd/display/dc/hwss/dce110/dce110_hwseq.c | 5 +++--
drivers/gpu/drm/amd/display/dc/hwss/dcn10/dcn10_hwseq.c | 4 ++--
drivers/gpu/drm/amd/display/dc/hwss/dcn31/dcn31_hwseq.c | 4 ++--
drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_hwseq.c | 8 ++++----
.../amd/display/dc/link/protocols/link_dp_capability.c | 2 +-
8 files changed, 17 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/clk_mgr/dce110/dce110_clk_mgr.c b/drivers/gpu/drm/amd/display/dc/clk_mgr/dce110/dce110_clk_mgr.c
index 78df96882d6ec..f8409453434c1 100644
--- a/drivers/gpu/drm/amd/display/dc/clk_mgr/dce110/dce110_clk_mgr.c
+++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/dce110/dce110_clk_mgr.c
@@ -195,7 +195,7 @@ void dce11_pplib_apply_display_requirements(
* , then change minimum memory clock based on real-time bandwidth
* limitation.
*/
- if ((dc->ctx->asic_id.chip_family == FAMILY_AI) &&
+ if (dc->bw_vbios && (dc->ctx->asic_id.chip_family == FAMILY_AI) &&
ASICREV_IS_VEGA20_P(dc->ctx->asic_id.hw_internal_rev) && (context->stream_count >= 2)) {
pp_display_cfg->min_memory_clock_khz = max(pp_display_cfg->min_memory_clock_khz,
(uint32_t) div64_s64(
diff --git a/drivers/gpu/drm/amd/display/dc/hubp/dcn10/dcn10_hubp.c b/drivers/gpu/drm/amd/display/dc/hubp/dcn10/dcn10_hubp.c
index bf399819ca800..22ac2b7e49aea 100644
--- a/drivers/gpu/drm/amd/display/dc/hubp/dcn10/dcn10_hubp.c
+++ b/drivers/gpu/drm/amd/display/dc/hubp/dcn10/dcn10_hubp.c
@@ -749,7 +749,8 @@ bool hubp1_is_flip_pending(struct hubp *hubp)
if (flip_pending)
return true;

- if (earliest_inuse_address.grph.addr.quad_part != hubp->request_address.grph.addr.quad_part)
+ if (hubp &&
+ earliest_inuse_address.grph.addr.quad_part != hubp->request_address.grph.addr.quad_part)
return true;

return false;
diff --git a/drivers/gpu/drm/amd/display/dc/hubp/dcn20/dcn20_hubp.c b/drivers/gpu/drm/amd/display/dc/hubp/dcn20/dcn20_hubp.c
index 6bba020ad6fbf..0637e4c552d8a 100644
--- a/drivers/gpu/drm/amd/display/dc/hubp/dcn20/dcn20_hubp.c
+++ b/drivers/gpu/drm/amd/display/dc/hubp/dcn20/dcn20_hubp.c
@@ -927,7 +927,8 @@ bool hubp2_is_flip_pending(struct hubp *hubp)
if (flip_pending)
return true;

- if (earliest_inuse_address.grph.addr.quad_part != hubp->request_address.grph.addr.quad_part)
+ if (hubp &&
+ earliest_inuse_address.grph.addr.quad_part != hubp->request_address.grph.addr.quad_part)
return true;

return false;
diff --git a/drivers/gpu/drm/amd/display/dc/hwss/dce110/dce110_hwseq.c b/drivers/gpu/drm/amd/display/dc/hwss/dce110/dce110_hwseq.c
index 1f2eb2f727dc1..45eb392f44932 100644
--- a/drivers/gpu/drm/amd/display/dc/hwss/dce110/dce110_hwseq.c
+++ b/drivers/gpu/drm/amd/display/dc/hwss/dce110/dce110_hwseq.c
@@ -949,7 +949,7 @@ void dce110_edp_backlight_control(
{
struct dc_context *ctx = link->ctx;
struct bp_transmitter_control cntl = { 0 };
- uint8_t pwrseq_instance;
+ uint8_t pwrseq_instance = 0;
unsigned int pre_T11_delay = OLED_PRE_T11_DELAY;
unsigned int post_T7_delay = OLED_POST_T7_DELAY;

@@ -1002,7 +1002,8 @@ void dce110_edp_backlight_control(
*/
/* dc_service_sleep_in_milliseconds(50); */
/*edp 1.2*/
- pwrseq_instance = link->panel_cntl->pwrseq_inst;
+ if (link->panel_cntl)
+ pwrseq_instance = link->panel_cntl->pwrseq_inst;

if (cntl.action == TRANSMITTER_CONTROL_BACKLIGHT_ON) {
if (!link->dc->config.edp_no_power_sequencing)
diff --git a/drivers/gpu/drm/amd/display/dc/hwss/dcn10/dcn10_hwseq.c b/drivers/gpu/drm/amd/display/dc/hwss/dcn10/dcn10_hwseq.c
index 1d2be574f6680..83942abd08e84 100644
--- a/drivers/gpu/drm/amd/display/dc/hwss/dcn10/dcn10_hwseq.c
+++ b/drivers/gpu/drm/amd/display/dc/hwss/dcn10/dcn10_hwseq.c
@@ -1554,7 +1554,7 @@ void dcn10_init_hw(struct dc *dc)
dc->clk_mgr->funcs->init_clocks(dc->clk_mgr);

/* Align bw context with hw config when system resume. */
- if (dc->clk_mgr->clks.dispclk_khz != 0 && dc->clk_mgr->clks.dppclk_khz != 0) {
+ if (dc->clk_mgr && dc->clk_mgr->clks.dispclk_khz != 0 && dc->clk_mgr->clks.dppclk_khz != 0) {
dc->current_state->bw_ctx.bw.dcn.clk.dispclk_khz = dc->clk_mgr->clks.dispclk_khz;
dc->current_state->bw_ctx.bw.dcn.clk.dppclk_khz = dc->clk_mgr->clks.dppclk_khz;
}
@@ -1674,7 +1674,7 @@ void dcn10_init_hw(struct dc *dc)
REG_UPDATE(DCFCLK_CNTL, DCFCLK_GATE_DIS, 0);
}

- if (dc->clk_mgr->funcs->notify_wm_ranges)
+ if (dc->clk_mgr && dc->clk_mgr->funcs->notify_wm_ranges)
dc->clk_mgr->funcs->notify_wm_ranges(dc->clk_mgr);
}

diff --git a/drivers/gpu/drm/amd/display/dc/hwss/dcn31/dcn31_hwseq.c b/drivers/gpu/drm/amd/display/dc/hwss/dcn31/dcn31_hwseq.c
index 746c522adf84c..3d4b31bd99469 100644
--- a/drivers/gpu/drm/amd/display/dc/hwss/dcn31/dcn31_hwseq.c
+++ b/drivers/gpu/drm/amd/display/dc/hwss/dcn31/dcn31_hwseq.c
@@ -256,10 +256,10 @@ void dcn31_init_hw(struct dc *dc)
if (!dcb->funcs->is_accelerated_mode(dcb) && dc->res_pool->hubbub->funcs->init_watermarks)
dc->res_pool->hubbub->funcs->init_watermarks(dc->res_pool->hubbub);

- if (dc->clk_mgr->funcs->notify_wm_ranges)
+ if (dc->clk_mgr && dc->clk_mgr->funcs->notify_wm_ranges)
dc->clk_mgr->funcs->notify_wm_ranges(dc->clk_mgr);

- if (dc->clk_mgr->funcs->set_hard_max_memclk && !dc->clk_mgr->dc_mode_softmax_enabled)
+ if (dc->clk_mgr && dc->clk_mgr->funcs->set_hard_max_memclk && !dc->clk_mgr->dc_mode_softmax_enabled)
dc->clk_mgr->funcs->set_hard_max_memclk(dc->clk_mgr);

if (dc->res_pool->hubbub->funcs->force_pstate_change_control)
diff --git a/drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_hwseq.c b/drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_hwseq.c
index d5e9aec52a059..25fe2e7c274b6 100644
--- a/drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_hwseq.c
+++ b/drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_hwseq.c
@@ -235,7 +235,7 @@ void dcn35_init_hw(struct dc *dc)
if (hws->funcs.enable_power_gating_plane)
hws->funcs.enable_power_gating_plane(dc->hwseq, true);
*/
- if (res_pool->hubbub->funcs->dchubbub_init)
+ if (res_pool->hubbub && res_pool->hubbub->funcs->dchubbub_init)
res_pool->hubbub->funcs->dchubbub_init(dc->res_pool->hubbub);
/* If taking control over from VBIOS, we may want to optimize our first
* mode set, so we need to skip powering down pipes until we know which
@@ -328,10 +328,10 @@ void dcn35_init_hw(struct dc *dc)
if (!dcb->funcs->is_accelerated_mode(dcb) && dc->res_pool->hubbub->funcs->init_watermarks)
dc->res_pool->hubbub->funcs->init_watermarks(dc->res_pool->hubbub);

- if (dc->clk_mgr->funcs->notify_wm_ranges)
+ if (dc->clk_mgr && dc->clk_mgr->funcs->notify_wm_ranges)
dc->clk_mgr->funcs->notify_wm_ranges(dc->clk_mgr);

- if (dc->clk_mgr->funcs->set_hard_max_memclk && !dc->clk_mgr->dc_mode_softmax_enabled)
+ if (dc->clk_mgr && dc->clk_mgr->funcs->set_hard_max_memclk && !dc->clk_mgr->dc_mode_softmax_enabled)
dc->clk_mgr->funcs->set_hard_max_memclk(dc->clk_mgr);

@@ -1041,7 +1041,7 @@ void dcn35_calc_blocks_to_gate(struct dc *dc, struct dc_state *context,
if (pipe_ctx->plane_res.hubp)
update_state->pg_pipe_res_update[PG_HUBP][pipe_ctx->plane_res.hubp->inst] = false;

- if (pipe_ctx->plane_res.dpp)
+ if (pipe_ctx->plane_res.dpp && pipe_ctx->plane_res.hubp)
update_state->pg_pipe_res_update[PG_DPP][pipe_ctx->plane_res.hubp->inst] = false;

if (pipe_ctx->plane_res.dpp || pipe_ctx->stream_res.opp)
diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c
index 46bb7a855bc21..60015e94c4aa8 100644
--- a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c
+++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c
@@ -2254,7 +2254,7 @@ bool dp_verify_link_cap_with_retries(

memset(&link->verified_link_cap, 0,
sizeof(struct dc_link_settings));
- if (!link_detect_connection_type(link, &type) || type == dc_connection_none) {
+ if (link->link_enc && (!link_detect_connection_type(link, &type) || type == dc_connection_none)) {
link->verified_link_cap = fail_safe_link_settings;
break;
} else if (dp_verify_link_cap(link, known_limit_link_setting, &fail_count)) {
--
2.43.0