There is a regular need in the kernel to provide a way to declare having a dynamically sized set of trailing elements in a structure. Kernel code should always use “flexible array members”[1] for these cases. The older style of one-element or zero-length arrays should no longer be used[2].
Refactor the code according to the use of a flexible-array member in struct phm_vce_clock_voltage_dependency_table, instead of a one-element array, and use the struct_size() helper to calculate the size for the allocation.
Also, save some heap space as the original code is multiplying table->numEntries by sizeof(struct phm_vce_clock_voltage_dependency_table) when it should have multiplied it by sizeof(struct phm_vce_clock_voltage_dependency_record) instead.
[1] https://en.wikipedia.org/wiki/Flexible_array_member [2] https://www.kernel.org/doc/html/v5.9-rc1/process/deprecated.html#zero-length...
Build-tested-by: kernel test robot lkp@intel.com Link: https://lore.kernel.org/lkml/5f7c5d35.pJToGs3H9khZK6ws%25lkp@intel.com/ Signed-off-by: Gustavo A. R. Silva gustavoars@kernel.org --- drivers/gpu/drm/amd/pm/inc/hwmgr.h | 2 +- .../gpu/drm/amd/pm/powerplay/hwmgr/processpptables.c | 11 ++++------- 2 files changed, 5 insertions(+), 8 deletions(-)
diff --git a/drivers/gpu/drm/amd/pm/inc/hwmgr.h b/drivers/gpu/drm/amd/pm/inc/hwmgr.h index ad614e32079e..b8e33325fac6 100644 --- a/drivers/gpu/drm/amd/pm/inc/hwmgr.h +++ b/drivers/gpu/drm/amd/pm/inc/hwmgr.h @@ -186,7 +186,7 @@ struct phm_acpclock_voltage_dependency_table {
struct phm_vce_clock_voltage_dependency_table { uint8_t count; - struct phm_vce_clock_voltage_dependency_record entries[1]; + struct phm_vce_clock_voltage_dependency_record entries[]; };
diff --git a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/processpptables.c b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/processpptables.c index b2ef76580c6a..7719f52e6d52 100644 --- a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/processpptables.c +++ b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/processpptables.c @@ -1135,15 +1135,12 @@ static int get_vce_clock_voltage_limit_table(struct pp_hwmgr *hwmgr, const ATOM_PPLIB_VCE_Clock_Voltage_Limit_Table *table, const VCEClockInfoArray *array) { - unsigned long table_size, i; + unsigned long i; struct phm_vce_clock_voltage_dependency_table *vce_table = NULL;
- table_size = sizeof(unsigned long) + - sizeof(struct phm_vce_clock_voltage_dependency_table) - * table->numEntries; - - vce_table = kzalloc(table_size, GFP_KERNEL); - if (NULL == vce_table) + vce_table = kzalloc(struct_size(vce_table, entries, table->numEntries), + GFP_KERNEL); + if (!vce_table) return -ENOMEM;
vce_table->count = table->numEntries;