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From: Peter Maydell <peter.maydell@linaro.org>
Date: Wed, 18 Jun 2014 13:53:15 +0100
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Subject: Re: [Qemu-devel] [PATCH v8 00/20] virtio endian-ambivalent target
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To: Stefan Hajnoczi <stefanha@gmail.com>
Cc: Kevin Wolf <kwolf@redhat.com>, Anthony Liguori <aliguori@amazon.com>, "Michael S. Tsirkin" <mst@redhat.com>, Rusty Russell <rusty@rustcorp.com.au>, Alexander Graf <agraf@suse.de>, QEMU Developers <qemu-devel@nongnu.org>, Juan Quintela <quintela@redhat.com>, "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>, Stefan Hajnoczi <stefanha@redhat.com>, Amit Shah <amit.shah@redhat.com>, Paolo Bonzini <pbonzini@redhat.com>, =?UTF-8?Q?Andreas_F=C3=A4rber?= <afaerber@suse.de>, Greg Kurz <gkurz@linux.vnet.ibm.com>

On 18 June 2014 11:38, Stefan Hajnoczi <stefanha@gmail.com> wrote:
> What bothers me is that real hardware can't do this.

Real hardware doesn't have "endianness matches guest CPU endianness"
semantics, which is what the virtio spec mandates...

> Given that VIRTIO
> 1.0 is always little-endian I guess this is just a temporary hack for
> ppc little-endian.  Would be nice to add a comment so it's clear why
> this approach is being taken instead of a cleaner solution.

Also for ARM big-endian, and indeed for any CPU with runtime
configurable endianness that wants to use the kernel virtio
drivers that exist in the real world rather than the theoretical
future ones that might some day be written for the 1.0 virtio
spec...

thanks
-- PMM