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Date: Mon, 10 Dec 2012 10:22:27 +0000
From: James Hogan <james.hogan@imgtec.com>
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To: "H. Peter Anvin" <hpa@zytor.com>
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        "Arnd Bergmann" <arnd@arndb.de>, Balbir Singh <bsingharora@gmail.com>,
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        Andrew Morton <akpm@linux-foundation.org>,
        Eric Paris <eparis@redhat.com>, Will Drewry <wad@chromium.org>,
        James Morris <james.l.morris@oracle.com>
Subject: Re: [PATCH v2 03/44] Add CONFIG_HAVE_64BIT_ALIGNED_STRUCT for taskstats
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On 08/12/12 03:43, H. Peter Anvin wrote:
> On 12/05/2012 08:08 AM, James Hogan wrote:
>> On 64 bit architectures with no efficient unaligned access, taskstats
>> has to add some padding to a reply to prevent unaligned access warnings.
>> However this also needs to apply to 32 bit architectures with 64 bit
>> struct alignment such as metag (which has 64 bit memory accesses).
> 
> Wait... 64-bit struct alignment on structures with only 32-bit members?
>  That might be... interesting... in a number of places...

Hi,

I'll rewrite the description as it's a bit misleading. On metag 64bit
struct alignment is required when it contains 64bit members, not if it
only contains 32bit members. Although metag is a 32bit arch, it can do
64bit memory accesses which must be aligned.

Thanks for taking a look.

James