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From: Rusty Russell <rusty@rustcorp.com.au>
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	<20130828080723.GD4696@stefanha-thinkpad.muc.redhat.com>
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Date: Wed, 04 Sep 2013 16:22:55 +0930
Message-ID: <87li3d6ptk.fsf@rustcorp.com.au>
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Subject: Re: [Qemu-devel] Would virtio support 64 bit address for vring
	virtqueue?
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To: "Xie, Huawei" <huawei.xie@intel.com>, Stefan Hajnoczi <stefanha@gmail.com>
Cc: "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, Stefan Hajnoczi <stefanha@redhat.com>

"Xie, Huawei" <huawei.xie@intel.com> writes:
> If this is the case, one possible fix would be:
> 	Write two continuous 32bit DWORD to combine a 64bit address
> 	Use the upper 12 bits of PFN val to indicate if it is combined write
> In this way, we wouldn't break other virtio driver, register layout
> and only need a few lines of modification.

Note that (with OASIS) we are currently working on a v1.0 of the virtio
spec.  I recommend the OASIS virtio-dev mailing list
( https://www.oasis-open.org/mlmanage/ ) and in particular the thread on
Michael Tsirkin's proposal on using PCI capabilities:

https://lists.oasis-open.org/archives/virtio-comment/201308/msg00087.html

Cheers,
Rusty.