ACPI: CPPC: Add NULL pointer check to cppc_get_perf()

Check cpc_desc against NULL in cppc_get_perf(), so it doesn't crash
down the road if cpc_desc is NULL.

Fixes: 0654cf05d1 ("ACPI: CPPC: Introduce cppc_get_nominal_perf()")
Reported-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: 5.15+ <stable@vger.kernel.org> # 5.15+
Tested-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
This commit is contained in:
Rafael J. Wysocki 2021-11-18 14:37:38 +01:00
parent 1360572566
commit 935dff305d
1 changed files with 8 additions and 1 deletions

View File

@ -998,7 +998,14 @@ static int cpc_write(int cpu, struct cpc_register_resource *reg_res, u64 val)
static int cppc_get_perf(int cpunum, enum cppc_regs reg_idx, u64 *perf)
{
struct cpc_desc *cpc_desc = per_cpu(cpc_desc_ptr, cpunum);
struct cpc_register_resource *reg = &cpc_desc->cpc_regs[reg_idx];
struct cpc_register_resource *reg;
if (!cpc_desc) {
pr_debug("No CPC descriptor for CPU:%d\n", cpunum);
return -ENODEV;
}
reg = &cpc_desc->cpc_regs[reg_idx];
if (CPC_IN_PCC(reg)) {
int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpunum);