From mboxrd@z Thu Jan  1 00:00:00 1970
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: [Qemu-ppc] KVM and variable-endianness guest CPUs
Date: Tue, 28 Jan 2014 11:36:13 +1100
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Cc: Victor Kamensky <victor.kamensky@linaro.org>,
	Thomas Falcon <tlfalcon@linux.vnet.ibm.com>,
	kvm-devel <kvm@vger.kernel.org>,
	QEMU Developers <qemu-devel@nongnu.org>,
	"qemu-ppc@nongnu.org" <qemu-ppc@nongnu.org>,
	"kvmarm@lists.cs.columbia.edu" <kvmarm@lists.cs.columbia.edu>,
	Christoffer Dall <christoffer.dall@linaro.org>
To: Peter Maydell <peter.maydell@linaro.org>
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On Mon, 2014-01-27 at 23:49 +0000, Peter Maydell wrote:
> 
> Er, what? If we make the array be guest's current order
> then by definition userspace has to look at the guest's
> current endianness. I agree that would be bad. Either
> of the two current proposals (host kernel order; guest
> CPU's native/natural/default-byte-order) avoid it, though.

No, this has nothing to do with the guest endianness, and
all to do about the (hopefully) byte-address invariant bus we have
on the processor.

Anyway, the existing crap is ABI so I suspect we have to stick with it,
just maybe document it better.

Ben.