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From: Arnd Bergmann <arnd@arndb.de>
To: Kyle McMartin <kyle@mcmartin.ca>
Subject: Re: [COMPAT] Add compat_merge64 helper
Date: Sat, 29 Sep 2007 01:52:12 +0200
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On Saturday 29 September 2007, Kyle McMartin wrote:
> 
> On Sat, Sep 29, 2007 at 01:38:23AM +0200, Arnd Bergmann wrote:
> > 1. Byte order matches the order in which 64 bit arguments are split
> >    in system call conventions on all platforms.
> 
> I checked powerpc, sparc, and mips, which are (besides parisc) the only
> 64-bit with 32-bit userspace big endian architectures that I could think
> of offhand. A quick grep shows sh64 too... Paul?
> 

s390 is big-endian as well, and while it does have really weird C calling
conventions for 64 bit arguments in 32 bit mode, these do not affect the
system call ABI, so we should be fine here.

ia64 and x86_64 are obviously little-endian, and I double-checked that they
work with this logic.

	Arnd <><