Re: [PATCH 2/2] kvm tools: Add virtio-9p

Sasha Levin
2011-05-26T14:36:51Z

On Thu, 2011-05-26 at 07:28 -0700, Venkateswararao Jujjuri wrote:
> Any progress on this? May I get more detailed instructions on how
> you did this trick? Basically booting on 9P/VirtIO.
>
> Thanks,
> JV
>

Ofcourse. This change didn't go into tools/kvm/ since we only support
the legacy 9p2000 protocol at the moment, which means that even though
we can boot - it's quite unusable to work with.

The trick is pretty simple: You need to name your virtio transport
"/dev/root" (I think it's currently named "local" in qemu). Once it's
named this way, boot with the following kernel cmdline added:
"root=/dev/root rootflags=rw,trans=virtio,version=9p2000 rootfstype=9p
rw" (You should be able to change version to one of the 9p2000
extensions).

I've noticed that the transport *has* to be named "/dev/root", naming it
something else (and adjusting the "root=" parameter) doesn't seem to
work.

Also, if it's named "/dev/root" I couldn't mount it as a simple
filesystem from within a guest - not as root.

--

Sasha.