2013-07-23 01:36:20

by Tang Chen

Subject: [PATCH 1/1] x86, acpi: Fix wrong checking condition in acpi_register_lapic().

We wanted to check if the acpi id is out of range. It should be:
if (id >= (MAX_LOCAL_APIC)).

Signed-off-by: Tang Chen <[email protected]>
---
arch/x86/kernel/acpi/boot.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index d81a972..2a15ae7 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -199,7 +199,7 @@ static void __cpuinit acpi_register_lapic(int id, u8 enabled)
{
unsigned int ver = 0;

- if (id >= (MAX_LOCAL_APIC-1)) {
+ if (id >= (MAX_LOCAL_APIC)) {
printk(KERN_INFO PREFIX "skipped apicid that is too big\n");
return;
}
--
1.7.10.1

2013-07-23 01:38:27

by Brown, Len

Subject: RE: [PATCH 1/1] x86, acpi: Fix wrong checking condition in acpi_register_lapic().

Reviewed-by: Len Brown <[email protected]>

2013-07-23 07:39:56

by Ingo Molnar

Subject: Re: [PATCH 1/1] x86, acpi: Fix wrong checking condition in acpi_register_lapic().

* Tang Chen <[email protected]> wrote:

> We wanted to check if the acpi id is out of range. It should be:
> if (id >= (MAX_LOCAL_APIC)).

Does this have any practical impact, or can it wait until v3.12?

> Signed-off-by: Tang Chen <[email protected]>
> ---
> arch/x86/kernel/acpi/boot.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
> index d81a972..2a15ae7 100644
> --- a/arch/x86/kernel/acpi/boot.c
> +++ b/arch/x86/kernel/acpi/boot.c
> @@ -199,7 +199,7 @@ static void __cpuinit acpi_register_lapic(int id, u8 enabled)
> {
> unsigned int ver = 0;
>
> - if (id >= (MAX_LOCAL_APIC-1)) {
> + if (id >= (MAX_LOCAL_APIC)) {

The parentheses are now superfluous.

Thanks,

Ingo

2013-07-23 07:52:52

by Tang Chen

Subject: Re: [PATCH 1/1] x86, acpi: Fix wrong checking condition in acpi_register_lapic().

On 07/23/2013 03:39 PM, Ingo Molnar wrote:
>
> * Tang Chen<[email protected]> wrote:
>
>> We wanted to check if the acpi id is out of range. It should be:
>> if (id>= (MAX_LOCAL_APIC)).
>
> Does this have any practical impact, or can it wait until v3.12?

I haven't tested out any impact now, just found it when reading the code.
We can wait until v3.12.

>
>> Signed-off-by: Tang Chen<[email protected]>
>> ---
>> arch/x86/kernel/acpi/boot.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
>> index d81a972..2a15ae7 100644
>> --- a/arch/x86/kernel/acpi/boot.c
>> +++ b/arch/x86/kernel/acpi/boot.c
>> @@ -199,7 +199,7 @@ static void __cpuinit acpi_register_lapic(int id, u8 enabled)
>> {
>> unsigned int ver = 0;
>>
>> - if (id>= (MAX_LOCAL_APIC-1)) {
>> + if (id>= (MAX_LOCAL_APIC)) {
>
> The parentheses are now superfluous.

Oh, yes. I'll send a new version without the parentheses.

Thanks.