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Subject: Re: [PATCH] prctl: implement PR_GET_ENDIAN for all architectures
From: James Bottomley <James.Bottomley@HansenPartnership.com>
To: Andrew Morton <akpm@linux-foundation.org>,
        Helge Deller <deller@gmx.de>
Cc: linux-kernel@vger.kernel.org, linux-parisc@vger.kernel.org,
        Michael Kerrisk <mtk.manpages@googlemail.com>,
        linux-api@vger.kernel.org
Date: Wed, 01 Feb 2017 15:12:12 -0800
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On Tue, 2017-01-31 at 16:26 -0800, Andrew Morton wrote:
> On Sat, 28 Jan 2017 12:13:10 +0100 Helge Deller <deller@gmx.de>
> wrote:
> 
> > The prctl(PR_GET_ENDIAN) syscall was added to Kernel 2.6.18, but
> > implemented for PowerPC only. This trivial patch adds support for 
> > this syscall for all other architectures.
> 
> Seems reasonable.  I guess.  Why is this needed?

I don't think it is other than for PPC.  If you're not variable endian
(which is only PPC to date), then you should know a priori what endian
you are from the #defines in userspace.

James