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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Tue, 10 Jan 2017 09:05:28 -0800
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Subject: Re: x86-64: Maintain 16-byte stack alignment
To: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Linux Crypto Mailing List <linux-crypto@vger.kernel.org>,
        Ingo Molnar <mingo@kernel.org>, Thomas Gleixner <tglx@linutronix.de>,
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        Ard Biesheuvel <ard.biesheuvel@linaro.org>
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On Tue, Jan 10, 2017 at 6:39 AM, Herbert Xu <herbert@gondor.apana.org.au> wrote:
>
> BTW this is with Debian gcc 4.7.2 which does not allow an 8-byte
> stack alignment as attempted by the Makefile:

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.

                 Linus