[PATCH 12/14] drm/amd/pm: Replace one-element array with flexible-array in struct phm_ppt_v1_voltage_lookup_table

Gustavo A. R. Silva
2020-10-07T16:04:24Z

struct phm_ppt_v1_voltage_lookup_table, instead of a one-element array,
and use the struct_size() helper to calculate the size for the allocation.

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.9-rc1/process/deprecated.html#zero-length-and-one-element-arrays

Build-tested-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/lkml/5f7d61df.jWrFfnjxGbjSkPOp%25lkp@intel.com/
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
---
drivers/gpu/drm/amd/pm/powerplay/hwmgr/hwmgr_ppt.h | 2 +-
.../drm/amd/pm/powerplay/hwmgr/process_pptables_v1_0.c | 10 +++-------
.../amd/pm/powerplay/hwmgr/vega10_processpptables.c | 10 +++-------
3 files changed, 7 insertions(+), 15 deletions(-)

diff --git a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/hwmgr_ppt.h b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/hwmgr_ppt.h
index 923cc04e405a..e11298cdeb30 100644
--- a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/hwmgr_ppt.h
+++ b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/hwmgr_ppt.h
@@ -86,7 +86,7 @@ typedef struct phm_ppt_v1_voltage_lookup_record phm_ppt_v1_voltage_lookup_record

struct phm_ppt_v1_voltage_lookup_table {
uint32_t count;
- phm_ppt_v1_voltage_lookup_record entries[1]; /* Dynamically allocate count entries. */
+ phm_ppt_v1_voltage_lookup_record entries[]; /* Dynamically allocate count entries. */
};
typedef struct phm_ppt_v1_voltage_lookup_table phm_ppt_v1_voltage_lookup_table;

diff --git a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/process_pptables_v1_0.c b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/process_pptables_v1_0.c
index 5d8016cd1986..426655b9c678 100644
--- a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/process_pptables_v1_0.c
+++ b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/process_pptables_v1_0.c
@@ -157,7 +157,7 @@ static int get_vddc_lookup_table(
uint32_t max_levels
)
{
- uint32_t table_size, i;
+ uint32_t i;
phm_ppt_v1_voltage_lookup_table *table;
phm_ppt_v1_voltage_lookup_record *record;
ATOM_Tonga_Voltage_Lookup_Record *atom_record;
@@ -165,12 +165,8 @@ static int get_vddc_lookup_table(
PP_ASSERT_WITH_CODE((0 != vddc_lookup_pp_tables->ucNumEntries),
"Invalid CAC Leakage PowerPlay Table!", return 1);

- table_size = sizeof(uint32_t) +
- sizeof(phm_ppt_v1_voltage_lookup_record) * max_levels;
-
- table = kzalloc(table_size, GFP_KERNEL);
-
- if (NULL == table)
+ table = kzalloc(struct_size(table, entries, max_levels), GFP_KERNEL);
+ if (!table)
return -ENOMEM;

table->count = vddc_lookup_pp_tables->ucNumEntries;
diff --git a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/vega10_processpptables.c b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/vega10_processpptables.c
index 4f6a73a2cf28..3d7f915381c8 100644
--- a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/vega10_processpptables.c
+++ b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/vega10_processpptables.c
@@ -1040,18 +1040,14 @@ static int get_vddc_lookup_table(
const ATOM_Vega10_Voltage_Lookup_Table *vddc_lookup_pp_tables,
uint32_t max_levels)
{
- uint32_t table_size, i;
+ uint32_t i;
phm_ppt_v1_voltage_lookup_table *table;

PP_ASSERT_WITH_CODE((vddc_lookup_pp_tables->ucNumEntries != 0),
"Invalid SOC_VDDD Lookup Table!", return 1);

- table_size = sizeof(uint32_t) +
- sizeof(phm_ppt_v1_voltage_lookup_record) * max_levels;
-
- table = kzalloc(table_size, GFP_KERNEL);
-
- if (table == NULL)
+ table = kzalloc(struct_size(table, entries, max_levels), GFP_KERNEL);
+ if (!table)
return -ENOMEM;

table->count = vddc_lookup_pp_tables->ucNumEntries;
--
2.27.0