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From: Peter Maydell <peter.maydell@linaro.org>
Date: Thu, 27 Aug 2015 13:27:54 +0100
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Subject: Re: [Qemu-devel] [PATCH 1/2] memory: allow zero size for
	adjust_endianness()
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To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>, Jason Wang <jasowang@redhat.com>, QEMU Developers <qemu-devel@nongnu.org>, Greg Kurz <gkurz@linux.vnet.ibm.com>

On 27 August 2015 at 13:25, Michael S. Tsirkin <mst@redhat.com> wrote:
> On Thu, Aug 27, 2015 at 01:20:52PM +0100, Peter Maydell wrote:
>> On 27 August 2015 at 13:17, Michael S. Tsirkin <mst@redhat.com> wrote:
>> > Basically the point is that ABI is extended to make
>> > ioeventfd with len = 0 mean "any length".
>> > 0 is thus not meaningless anymore.
>>
>> But how can you do adjustment for incorrect endianness
>> if you don't know the size of the data that you're
>> trying to work with? That's why this switch insists
>> that the size is 1, 2, 4 or 8.

> For kvm at least, "any length" implies "any data".
> So data is eventually discarded, we don't really need
> to adjust it for endian-ness.

I'm still confused. If you have data it needs to be
adjusted. If we're not actually doing anything with
the data why are we calling this function in the first
place?

-- PMM