From mboxrd@z Thu Jan  1 00:00:00 1970
From: Herbert Xu <herbert@gondor.apana.org.au>
Subject: Re: x86-64: Maintain 16-byte stack alignment
Date: Thu, 12 Jan 2017 15:05:34 +0800
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Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
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        Ingo Molnar <mingo@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
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        Ard Biesheuvel <ard.biesheuvel@linaro.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
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On Tue, Jan 10, 2017 at 09:05:28AM -0800, Linus Torvalds wrote:
>
> I'm pretty sure we have random asm code that may not maintain a
> 16-byte stack alignment when it calls other code (including, in some
> cases, calling C code).
> 
> So I'm not at all convinced that this is a good idea. We shouldn't
> expect 16-byte alignment to be something trustworthy.

So what if we audited all the x86 assembly code to fix this? Would
it then be acceptable to do a 16-byte aligned stack?

On the face of it it doesn't seem to be a huge amount of code
assuming they mostly live under arch/x86.

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