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_acp_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_acp_clock_voltage_dependency_table) when it should have multiplied it by sizeof(phm_acp_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/5f7c5d3c.TyfOhg%2FA6JycL6ZN%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 2f1886bc5535..361cb1125351 100644 --- a/drivers/gpu/drm/amd/pm/inc/hwmgr.h +++ b/drivers/gpu/drm/amd/pm/inc/hwmgr.h @@ -150,7 +150,7 @@ struct phm_acp_clock_voltage_dependency_record {
struct phm_acp_clock_voltage_dependency_table { uint32_t count; - struct phm_acp_clock_voltage_dependency_record entries[1]; + struct phm_acp_clock_voltage_dependency_record entries[]; };
struct phm_vce_clock_voltage_dependency_record { diff --git a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/processpptables.c b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/processpptables.c index 305d95c4162d..a1b198045978 100644 --- a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/processpptables.c +++ b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/processpptables.c @@ -1194,15 +1194,12 @@ static int get_acp_clock_voltage_limit_table(struct pp_hwmgr *hwmgr, struct phm_acp_clock_voltage_dependency_table **ptable, const ATOM_PPLIB_ACPClk_Voltage_Limit_Table *table) { - unsigned table_size, i; + unsigned long i; struct phm_acp_clock_voltage_dependency_table *acp_table;
- table_size = sizeof(unsigned long) + - sizeof(struct phm_acp_clock_voltage_dependency_table) * - table->numEntries; - - acp_table = kzalloc(table_size, GFP_KERNEL); - if (NULL == acp_table) + acp_table = kzalloc(struct_size(acp_table, entries, table->numEntries), + GFP_KERNEL); + if (!acp_table) return -ENOMEM;
acp_table->count = (unsigned long)table->numEntries;