Public bug reported: On LVM systems where an LV is fronted by a dm-writecache LV grub-probe fails to identify the filesystem type:
root@sunny:~# grub-probe -d /dev/mapper/SUNNY-usr_local -t fs error: invalid segment. error: invalid segment. grub-probe: error: disk `lvmid/9jfMwj-Zq6X-U8VT-Dt7o-8NQO-CZnP-8SIDgx/H8qr1q-N9se-U1iU-2HpR-zgIR-BiEw-bOBwAM' not found. root@sunny:~# file -sL /dev/mapper/SUNNY-usr_local /dev/mapper/SUNNY-usr_local: Linux rev 1.0 ext4 filesystem data, UUID=63874235-ad0b-4e60-8638-4121e5d5664a, volume name "usr_local" (extents) (64bit) (large files) (huge files) The error reports percolate up to "update-grub" / "grub-mkconfig" giving the impression there's something very wrong and reboot might fail. In this case though grub-probe is being triggered by os-prober (via /etc/grub.d/30_os-prober and /usr/lib/os-probes/50mounted-tests /dev/mapper/SUNNY-usr_local) ** Affects: grub2 (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1947336 Title: grub-probe: info: unknown LVM type writecache To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1947336/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs