Comment 8 for bug 986797

No surprise here, I'd installed grub to the root partition (sda16) while installing this test OS:

lance@lance-desktop:~$ grub-probe -vv --target=device /
grub-probe: info: cannot open `/boot/grub/device.map'.
/dev/sda16

Is this the rest of what you wanted:

lance@lance-desktop:~$ cat /proc/self/mountinfo
15 20 0:14 / /sys rw,nosuid,nodev,noexec,relatime - sysfs sysfs rw
16 20 0:3 / /proc rw,nosuid,nodev,noexec,relatime - proc proc rw
17 20 0:5 / /dev rw,relatime - devtmpfs udev rw,size=1018416k,nr_inodes=214663,mode=755
18 17 0:11 / /dev/pts rw,nosuid,noexec,relatime - devpts devpts rw,gid=5,mode=620,ptmxmode=000
19 20 0:15 / /run rw,nosuid,relatime - tmpfs tmpfs rw,size=410268k,mode=755
20 1 259:0 / / rw,relatime - ext4 /dev/disk/by-uuid/1966e720-b7df-41ee-a3d5-15d68cc7784e rw,errors=remount-ro,user_xattr,acl,barrier=1,data=ordered
21 15 0:16 / /sys/fs/fuse/connections rw,relatime - fusectl none rw
22 15 0:6 / /sys/kernel/debug rw,relatime - debugfs none rw
23 15 0:10 / /sys/kernel/security rw,relatime - securityfs none rw
24 19 0:17 / /run/lock rw,nosuid,nodev,noexec,relatime - tmpfs none rw,size=5120k
25 19 0:18 / /run/shm rw,nosuid,nodev,relatime - tmpfs none rw
26 16 0:19 / /proc/sys/fs/binfmt_misc rw,nosuid,nodev,noexec,relatime - binfmt_misc binfmt_misc rw
28 20 0:20 / /home/lance/.gvfs rw,nosuid,nodev,relatime - fuse.gvfs-fuse-daemon gvfs-fuse-daemon rw,user_id=1000,group_id=1000

Or do I need to poke about in the history logs?

I'm super tired ATM so excuse me if I'm being dense. One thing I think I should mention is that of these four errors the first to appear during the upgrade process was bug 986798 if that's helpful.