According commit d640113fe(ACPI: processor: fix acpi_get_cpuid for UP
processor), Bios may not provide _MAT or MADT tables and acpi_get_apicid()
always returns -1. For these cases, original code will pass apic_id with
vaule of -1 to acpi_map_cpuid() and it will check the acpi_id. If acpi_id
is equal to zero, ignores apic_id and return zero for CPU0.
Commit b981513(ACPI / scan: bail out early if failed to parse APIC
ID for CPU) changed the behavior. Return ENODEV when find apic_id is
less than zero after calling acpi_get_apicid(). This causes acpi-cpufreq
driver fails to be loaded on some machines. This patch is to fix it.
Reference:https://bugzilla.kernel.org/show_bug.cgi?id=73781
Cc: [email protected] v3.14
Reported-and-tested-by: KATO Hiroshi <[email protected]>
Reported-and-tested-by: Stuart Foster <[email protected]>
Signed-off-by: Lan Tianyu <[email protected]>
---
Change since V1:
Add a check for pr->apic_id in the acpi_processor_hotadd_init()
to avoid invalid memory access.
drivers/acpi/acpi_processor.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
index c29c2c3..b06f5f5 100644
--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -170,6 +170,9 @@ static int acpi_processor_hotadd_init(struct acpi_processor *pr)
acpi_status status;
int ret;
+ if (pr->apic_id == -1)
+ return -ENODEV;
+
status = acpi_evaluate_integer(pr->handle, "_STA", NULL, &sta);
if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_PRESENT))
return -ENODEV;
@@ -260,10 +263,8 @@ static int acpi_processor_get_info(struct acpi_device *device)
}
apic_id = acpi_get_apicid(pr->handle, device_declaration, pr->acpi_id);
- if (apic_id < 0) {
+ if (apic_id < 0)
acpi_handle_debug(pr->handle, "failed to get CPU APIC ID.\n");
- return -ENODEV;
- }
pr->apic_id = apic_id;
cpu_index = acpi_map_cpuid(pr->apic_id, pr->acpi_id);
--
1.8.4.rc0.1.g8f6a3e5.dirty
On Wednesday, April 30, 2014 03:46:33 PM Lan Tianyu wrote:
> According commit d640113fe(ACPI: processor: fix acpi_get_cpuid for UP
> processor), Bios may not provide _MAT or MADT tables and acpi_get_apicid()
> always returns -1. For these cases, original code will pass apic_id with
> vaule of -1 to acpi_map_cpuid() and it will check the acpi_id. If acpi_id
> is equal to zero, ignores apic_id and return zero for CPU0.
>
> Commit b981513(ACPI / scan: bail out early if failed to parse APIC
> ID for CPU) changed the behavior. Return ENODEV when find apic_id is
> less than zero after calling acpi_get_apicid(). This causes acpi-cpufreq
> driver fails to be loaded on some machines. This patch is to fix it.
>
> Reference:https://bugzilla.kernel.org/show_bug.cgi?id=73781
> Cc: [email protected] v3.14
> Reported-and-tested-by: KATO Hiroshi <[email protected]>
> Reported-and-tested-by: Stuart Foster <[email protected]>
> Signed-off-by: Lan Tianyu <[email protected]>
> ---
> Change since V1:
> Add a check for pr->apic_id in the acpi_processor_hotadd_init()
> to avoid invalid memory access.
Queued up for the next pull request, thanks!
> drivers/acpi/acpi_processor.c | 7 ++++---
> 1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
> index c29c2c3..b06f5f5 100644
> --- a/drivers/acpi/acpi_processor.c
> +++ b/drivers/acpi/acpi_processor.c
> @@ -170,6 +170,9 @@ static int acpi_processor_hotadd_init(struct acpi_processor *pr)
> acpi_status status;
> int ret;
>
> + if (pr->apic_id == -1)
> + return -ENODEV;
> +
> status = acpi_evaluate_integer(pr->handle, "_STA", NULL, &sta);
> if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_PRESENT))
> return -ENODEV;
> @@ -260,10 +263,8 @@ static int acpi_processor_get_info(struct acpi_device *device)
> }
>
> apic_id = acpi_get_apicid(pr->handle, device_declaration, pr->acpi_id);
> - if (apic_id < 0) {
> + if (apic_id < 0)
> acpi_handle_debug(pr->handle, "failed to get CPU APIC ID.\n");
> - return -ENODEV;
> - }
> pr->apic_id = apic_id;
>
> cpu_index = acpi_map_cpuid(pr->apic_id, pr->acpi_id);
>
--
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.