From: Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [kernel-hardening] Re: [PATCH v2 1/4] siphash: add
 cryptographically secure hashtable function
Date: Thu, 15 Dec 2016 13:14:16 -0800
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To: "Jason A. Donenfeld" <Jason@zx2c4.com>
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On Thu, Dec 15, 2016 at 1:11 PM, Jason A. Donenfeld <Jason@zx2c4.com> wrote:
>
> Indeed, I stand corrected. But in any case, the use of __aligned(8) in
> the patchset ensures that things are fixed and that we don't have this
> issue.

I think you can/should just use the natural alignment for "u64".

For architectures that need 8-byte alignment, u64 will already be
properly aligned. For architectures (like x86-32) that only need
4-byte alignment, you get it.

              Linus