diff mbox series

[v7,04/14] ACPI: CPPC: Check present CPUs for determining _CPC is valid

Message ID 20211224010508.110159-5-ray.huang@amd.com
State New
Headers show
Series cpufreq: Introduce a new AMD CPU frequency control mechanism | expand

Commit Message

Huang Rui Dec. 24, 2021, 1:04 a.m. UTC 
From: Mario Limonciello <mario.limonciello@amd.com>

As this is a static check, it should be based upon what is currently
present on the system. This makes probeing more deterministic.

While local APIC flags field (lapic_flags) of cpu core in MADT table is
0, then the cpu core won't be enabled. In this case, _CPC won't be found
in this core, and return back to _CPC invalid with walking through
possible cpus (include disable cpus). This is not expected, so switch to
check present CPUs instead.

Reported-by: Jinzhou Su <Jinzhou.Su@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Huang Rui <ray.huang@amd.com>
---
 drivers/acpi/cppc_acpi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
index df2933c28bec..0c4f7005818e 100644
--- a/drivers/acpi/cppc_acpi.c
+++ b/drivers/acpi/cppc_acpi.c
@@ -413,7 +413,7 @@  bool acpi_cpc_valid(void)
 	struct cpc_desc *cpc_ptr;
 	int cpu;
 
-	for_each_possible_cpu(cpu) {
+	for_each_present_cpu(cpu) {
 		cpc_ptr = per_cpu(cpc_desc_ptr, cpu);
 		if (!cpc_ptr)
 			return false;