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 10:34:51 +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>,
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	"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 Wed, 2014-01-22 at 20:02 +0000, Peter Maydell wrote:
> 
> Defining it as being always guest-order would mean that
> userspace had to continually look at the guest CPU
> endianness bit, which is annoying and awkward.
> 
> Defining it as always host-endian order is the most
> reasonable option available. It also happens to work
> for the current QEMU code, which is nice.

No.

Having a byte array coming in that represents what the CPU does in its
current byte order means you do *NOT* need to query the endianness of
the guest CPU from userspace.

Ben.