DF-3048 run log (fixed ext2fs.ko module, same kernel #0 Jul 2 build):

$ /root/vntool attach 0 /root/df3048.img
attached /root/df3048.img size=0
$ mount -t ext2fs -o ro /dev/vn0 /mnt/e2
mount_ext2fs: /dev/vn0: Invalid argument          <- new mount-time check
MOUNT-RC=71
$ stat /mnt/e2/lost+found
stat: /mnt/e2/lost+found: stat: No such file or directory
STAT-RC=1
$ echo ALIVE-3048
ALIVE-3048                                          <- no panic, guest healthy

(fix evidence: mount now rejected with EINVAL from the
 "inode count exceeds groups x inodes per group" check; console shows no
 panic, no trap)