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Date: Wed, 8 Dec 2010 14:30:58 +0000
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Subject: Re: [Qemu-devel] Booting from VirtIO disk
From: Stefan Hajnoczi <stefanha@gmail.com>
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To: =?UTF-8?B?4KSF4KSo4KWB4KSc?= <anuj01@gmail.com>
Cc: qemu-devel@nongnu.org

2010/12/8 =E0=A4=85=E0=A4=A8=E0=A5=81=E0=A4=9C <anuj01@gmail.com>:
> Hi list
>
> I got confused after observing that there is no support for VirtIO
> block devices in Seabios supplied with Qemu-0.12.3. But still it can
> accept a VirtIO disk as a bootable device and perfectly boots from it.
> Then How it's done?
>
> But I can see the VirtIO block device code in Seabios source supplied
> with Qemu-0.13.0.

Before SeaBIOS had native support for virtio-blk there was the extboot
option ROM which could boot from virtio-blk devices by reading a
special I/O port (it does not speak virtio-blk, see qemu-kvm.git
hw/extboot.c).

Stefan