From: Herbert Xu <herbert@gondor.apana.org.au>
Subject: Re: x86-64: Maintain 16-byte stack alignment
Date: Fri, 13 Jan 2017 16:38:41 +0800
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Cc: Josh Poimboeuf <jpoimboe@redhat.com>,
        Andy Lutomirski <luto@amacapital.net>,
        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>,
        Andy Lutomirski <luto@kernel.org>,
        Ard Biesheuvel <ard.biesheuvel@linaro.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
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On Thu, Jan 12, 2017 at 01:40:54PM -0800, Linus Torvalds wrote:
> 
> The 8-byte alignment mainly makes sense when the basic call sequence
> just adds 8 bytes, and you have functions without frames (that still
> call other functions).

The question is does it really make sense to save those 8 bytes
of padding on x86-64 when arm64 apparently also requires 16-byte
stack alignment.

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