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Subject: Re: [Qemu-devel] [Qemu-ppc] KVM and variable-endianness guest CPUs
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To: Peter Maydell <peter.maydell@linaro.org>
Cc: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>, kvm-devel <kvm@vger.kernel.org>, Victor Kamensky <victor.kamensky@linaro.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>

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.