OK, I have a new 2.6.38 kernel with virtio_blk.ko. This solves the failure to find ext2 root device.
Still not having any luck running the test-tool to completion. There is no /sys in the guest root image. There is also no /etc/fstab (is that expected?) There is no ethernet interface even though it looks like it can load virtio_net.
febootstrap: internal insmod virtio_balloon.ko
febootstrap: picked /sys/block/vdb/dev as root device
febootstrap: creating /dev/root as block special 251:16
febootstrap: mounting new root on /root
febootstrap: chroot
/proc/uptime: No such file or directory
Starting /init script ...
warning: can't open /etc/fstab: No such file or directory
mount: mount point /sys does not exist
cannot open /dev/null
[ 1.518238] udevd (45): /proc/45/oom_adj is deprecated, please use /proc/45/oom_score_adj instead.
Cannot access the Hardware Clock via any known method.
Use the --debug option to see the details of our search for an access method.
SIOCSIFADDR: No such device
eth0: ERROR while getting interface flags: No such device
SIOCADDRT: No such process
Failed to find sysfs mount point
read_urandom: /dev/urandom: open failed: No such file or directory
Failed to find sysfs mount point
read_urandom: /dev/urandom: open failed: No such file or directory
/init: line 73: /sys/block/vd*/queue/rotational: No such file or directory
/dev:
total 4
-rw-r--r-- 1 0 0 30 Aug 15 22:12 kmsg
rootfs / rootfs rw 0 0
proc /proc proc rw,relatime 0 0
/dev/root / ext2 rw,noatime,errors=continue 0 0
/proc /proc proc rw,relatime 0 0
Failed to find sysfs mount point
read_urandom: /dev/urandom: open failed: No such file or directory
Failed to find sysfs mount point
read_urandom: /dev/urandom: open failed: No such file or directory
Failed to find sysfs mount point
read_urandom: /dev/urandom: open failed: No such file or directory
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)
Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt Iface
Module Size Used by
virtio_balloon 4416 0
virtio_pci 6621 0
virtio_net 13053 0
virtio_blk 5631 1
virtio_console 14773 0
virtio_rng 2308 0
virtio 4824 6 virtio_balloon,virtio_pci,virtio_net,virtio_blk,virtio_console,virtio_rng
virtio_ring 5807 6 virtio_balloon,virtio_pci,virtio_net,virtio_blk,virtio_console,virtio_rng
sparse_keymap 4178 0
sym53c8xx 75987 0
scsi_transport_spi 25047 1 sym53c8xx
crc7 1458 0
crc_ccitt 1707 0
crc32c 3015 0
crc_itu_t 1747 0
Mon Aug 15 22:12:41 UTC 2011
uptime: 1.76 0.21
verbose daemon enabled
linux commmand line: panic=1 console=ttyS0 udevtimeout=300 noapic acpi=off printk.time=1 cgroup_disable=memory selinux=0 guestfs_verbose=1 TERM=rxvt
Failed to connect to virtio-serial channel.