[Qemu-devel] virtfs error reporting?

[Rob Landley <rlandley@parallels.com>]

So on the host side I'm trying to do this:

$ qemu -cpu pentium3 -nographic -no-reboot -kernel bzImage \
  -hda hda.sqf -append 'root=/dev/hda rw init=/sbin/init.sh panic=1 \
  PATH=/bin:/sbin console=ttyS0 HOST=i686 ' -net nic,model=e1000 \
  -net user -virtfs local,path=../root-filesystem-i686,security_model=mapped,mount_tag=root

And on the guest side I'm trying to do this:

  mount -t 9p -o ro,trans=virtio,version=9p2000.L root /mnt

And it's saying:

  mount: mounting root on /mnt failed: No such device

No idea what I'm doing wrong, "no such device" is not an informative
error message.

There's no obvious way to get the Linux client to tell me what tags
are available.  "What can I mount?  Do you see anything?"  I've
looked under /proc and /sys for "virtio"...  It's entirely possible
I'm missing something in my kernel .config but who knows what?

I note that qemu was sitting down and SULKING unless I specified the
security_model (I'm mounting read only, I don't care, but there
doesn't seem to be any way to DO a read-only export).  I'm guessing
based on the fact it stopped complaining that it is in fact exporting
something (and thus not upset I gave it a relative path, although giving
it an absolute path made no difference...)

Any clues?

Rob