Re: [git pull] x86 fixes

H. Peter Anvin
2008-07-24T20:39:49Z

Linus Torvalds wrote:
>
> On Thu, 24 Jul 2008, Ingo Molnar wrote:
>> Hugh Dickins (1):
>> x86: BUILD_IRQ say .text to avoid .data.percpu
>>
>> diff --git a/arch/x86/kernel/irqinit_64.c b/arch/x86/kernel/irqinit_64.c
>> index 0373e88..9414125 100644
>> --- a/arch/x86/kernel/irqinit_64.c
>> +++ b/arch/x86/kernel/irqinit_64.c
>> @@ -43,7 +43,7 @@
>>
>> #define BUILD_IRQ(nr) \
>> asmlinkage void IRQ_NAME(nr); \
>> - asm("\n.p2align\n" \
>> + asm("\n.text\n.p2align\n" \
>> "IRQ" #nr "_interrupt:\n\t" \
>> "push $~(" #nr ") ; " \
>> "jmp common_interrupt");
>
> I do not think this is a good idea AT ALL.
>
> You need a ".previous" there too, otherwise any random C code that doesn't
> _happen_ to change segments will now possibly put some random variable in
> the .text segment.
>
> And yes, dependign on just where the BUILD_IRQ() is, and what is around
> it, and what compiler version we have, this bug may or may not show. But
> it's still _wrong_.
>
> I pulled it, will fix up by hand.

You're obviously right here; thanks for taking care of it.

-hpa