Re: x86-64: Maintain 16-byte stack alignment

From: Herbert Xu
Date: Tue Jan 10 2017 - 22:15:37 EST


On Tue, Jan 10, 2017 at 05:30:48PM +0000, Ard Biesheuvel wrote:
>
> Apologies for introducing this breakage. It seemed like an obvious and
> simple cleanup, so I didn't even bother to mention it in the commit
> log, but if the kernel does not guarantee 16 byte alignment, I guess
> we should revert to the old method. If SSE instructions are the only
> ones that require this alignment, then I suppose not having a ABI
> conforming stack pointer should not be an issue in general.

I think we need to address this regardless of your patch. You
won't be the last person to use __attribute__ to get 16-byte
alignment on the stack.

Cheers,
--
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
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