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Date:   Wed, 13 Mar 2019 15:21:43 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Arnd Bergmann <arnd@arndb.de>
Cc:     Qian Cai <cai@lca.pw>, Jason Gunthorpe <jgg@mellanox.com>,
        "akpm@linux-foundation.org" <akpm@linux-foundation.org>,
        "linux-mm@kvack.org" <linux-mm@kvack.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Mark Rutland <mark.rutland@arm.com>
Subject: Re: [PATCH] mm/debug: add a cast to u64 for atomic64_read()
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On Wed, Mar 13, 2019 at 02:46:55PM +0100, Arnd Bergmann wrote:
> I thiunk it needs an '__attribute__((aligned(8)))' annotation at least on
> x86-32, 

I _hate_ that s64 isn't already natively aligned.

Anyway, yes, unaligned atomics are a _bad_ idea if they work at all.