http://bugzilla.opensuse.org/show_bug.cgi?id=1042551
http://bugzilla.opensuse.org/show_bug.cgi?id=1042551#c1
Andreas Stieger
Using ext4, this setup works well. Using btrfs it works until os-prober is launched (IMHO due to kernel or grub update) on the host. os-prober tries to mount all btrfs partitions regardless if they are already mount in a client. This destroys the btrfs filesystem.
Interesting. Looking at /usr/lib/os-probes/50mounted-tests it would seem that btrfs is handled in a special fashion, in particular not being mounted read-only:
if [ "$types" = btrfs ]; then [...] else [...] if mount -o ro -t "$type" "$partition" "$tmpmnt" 2>/dev/null;
and later:
# all btrfs subvol processing here. Handle both unmounted and # mounted subvolumes. if [ "$types" = btrfs ]; then debug "begin btrfs processing for $UUID" # note that the btrfs volume must not be mounted ro if mount -t btrfs -U "$UUID" "$tmpmnt" 2>/dev/null; then debug "btrfs volume $UUID mounted"
So the developer must have been aware of a requirements of mounting btrfs read-write here, which breaks the KVM scenario. Assigning to SLE maintainer. -- You are receiving this mail because: You are on the CC list for the bug.