[PATCH] drm/amd/display: Add check for kzalloc

[Jiasheng Jiang]

As kzalloc may fail and return NULL pointer, it should be better to check
the return value in order to avoid the NULL pointer dereference.
Moreover, dcn3_clk_mgr_construct should return the error and
should be checked cascadingly.

Fixes: 4d55b0dd1cdd ("drm/amd/display: Add DCN3 CLK_MGR")
Signed-off-by: Jiasheng Jiang <jiasheng at iscas.ac.cn>
---
 drivers/gpu/drm/amd/display/dc/clk_mgr/clk_mgr.c         | 9 ++++++---
 .../gpu/drm/amd/display/dc/clk_mgr/dcn30/dcn30_clk_mgr.c | 6 +++++-
 .../gpu/drm/amd/display/dc/clk_mgr/dcn30/dcn30_clk_mgr.h | 2 +-
 3 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/clk_mgr/clk_mgr.c b/drivers/gpu/drm/amd/display/dc/clk_mgr/clk_mgr.c
index f276abb63bcd..c08916bd5650 100644
--- a/drivers/gpu/drm/amd/display/dc/clk_mgr/clk_mgr.c
+++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/clk_mgr.c
@@ -257,15 +257,18 @@ struct clk_mgr *dc_clk_mgr_create(struct dc_context *ctx, struct pp_smu_funcs *p
 			return NULL;
 		}
 		if (ASICREV_IS_SIENNA_CICHLID_P(asic_id.hw_internal_rev)) {
-			dcn3_clk_mgr_construct(ctx, clk_mgr, pp_smu, dccg);
+			if (dcn3_clk_mgr_construct(ctx, clk_mgr, pp_smu, dccg))
+				return NULL;
 			return &clk_mgr->base;
 		}
 		if (ASICREV_IS_DIMGREY_CAVEFISH_P(asic_id.hw_internal_rev)) {
-			dcn3_clk_mgr_construct(ctx, clk_mgr, pp_smu, dccg);
+			if (dcn3_clk_mgr_construct(ctx, clk_mgr, pp_smu, dccg))
+				return NULL;
 			return &clk_mgr->base;
 		}
 		if (ASICREV_IS_BEIGE_GOBY_P(asic_id.hw_internal_rev)) {
-			dcn3_clk_mgr_construct(ctx, clk_mgr, pp_smu, dccg);
+			if (dcn3_clk_mgr_construct(ctx, clk_mgr, pp_smu, dccg))
+				return NULL;
 			return &clk_mgr->base;
 		}
 		if (asic_id.chip_id == DEVICE_ID_NV_13FE) {
diff --git a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn30/dcn30_clk_mgr.c b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn30/dcn30_clk_mgr.c
index 3ce0ee0d012f..86c29dc45b70 100644
--- a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn30/dcn30_clk_mgr.c
+++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn30/dcn30_clk_mgr.c
@@ -517,7 +517,7 @@ struct clk_mgr_funcs dcn3_fpga_funcs = {
 };
 
 /*todo for dcn30 for clk register offset*/
-void dcn3_clk_mgr_construct(
+int dcn3_clk_mgr_construct(
 		struct dc_context *ctx,
 		struct clk_mgr_internal *clk_mgr,
 		struct pp_smu_funcs *pp_smu,
@@ -568,11 +568,15 @@ void dcn3_clk_mgr_construct(
 	dce_clock_read_ss_info(clk_mgr);
 
 	clk_mgr->base.bw_params = kzalloc(sizeof(*clk_mgr->base.bw_params), GFP_KERNEL);
+	if (!clk_mgr->base.bw_params)
+		return -ENOMEM;
 
 	/* need physical address of table to give to PMFW */
 	clk_mgr->wm_range_table = dm_helpers_allocate_gpu_mem(clk_mgr->base.ctx,
 			DC_MEM_ALLOC_TYPE_GART, sizeof(WatermarksExternal_t),
 			&clk_mgr->wm_range_table_addr);
+
+	return 0;
 }
 
 void dcn3_clk_mgr_destroy(struct clk_mgr_internal *clk_mgr)
diff --git a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn30/dcn30_clk_mgr.h b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn30/dcn30_clk_mgr.h
index 2cd95ec38266..8bdfed735184 100644
--- a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn30/dcn30_clk_mgr.h
+++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn30/dcn30_clk_mgr.h
@@ -88,7 +88,7 @@
 #endif
 void dcn3_init_clocks(struct clk_mgr *clk_mgr_base);
 
-void dcn3_clk_mgr_construct(struct dc_context *ctx,
+int dcn3_clk_mgr_construct(struct dc_context *ctx,
 		struct clk_mgr_internal *clk_mgr,
 		struct pp_smu_funcs *pp_smu,
 		struct dccg *dccg);
-- 
2.25.1