On Wed, Jul 06, 2016 at 05:33:01PM +0300, Maxim Perevedentsev wrote: > Hello everyone! > > I have an issue with OpenSUSE-42.1 (I guess this is the only distro > with btrfs snapshots by default). > As we remember, list_filesystems returns btrfs snapshots along with devices. > > ><fs> list-filesystems > /dev/sda1: swap > btrfsvol:/dev/sda2/@: btrfs > btrfsvol:/dev/sda2/@/.snapshots: btrfs > btrfsvol:/dev/sda2/@/.snapshots/1/snapshot: btrfs > btrfsvol:/dev/sda2/@/.snapshots/2/snapshot: btrfs > ... > btrfsvol:/dev/sda2/@/.snapshots/16/snapshot: btrfs > /dev/sda2: btrfs > > > The btrfs snapshots are not block devices, so an error is thrown by > RESOLVE_DEVICE macro in stubs.c. That means we will get an error > trying to call blockdev - oriented functions at these devices. > > ========================= > > After grepping "list_filesystems" issues were found in: > - virt-sparsify (in-place and copying): is_lv > - virt-filesystems: blockdev_getsize64 > - virt-cat (inspect_os) treats this as multiboot system and refuses > to proceed > - virt-rescue --suggest suggests all snapshots (maybe this is correct) > - virt-sysprep --operation fs-uuids goes into infinite loop > > [ 144.2] Performing "fs-uuids" ... > virt-sysprep: warning: cannot set random UUID on filesystem > btrfsvol:/dev/sda2/@/.snapshots/16/snapshot type btrfs: set_uuid: > set_uuid_stub: btrfsvol:/dev/sda2/@/.snapshots/16/snapshot: expecting a > device name
The specific problem is that set_uuid is declared to take a Device as the first parameter [see generator/action.ml], whereas I believe it should take a Mountable instead. Compare it to how vfs_uuid is declared in the same file. This is simply a bug in generator/action.ml, and I believe a simple one line patch should fix it. > virt-sysprep: warning: cannot set random UUID on filesystem > btrfsvol:/dev/sda2/@/.snapshots/1/snapshot type btrfs: set_uuid: > set_uuid_stub: btrfsvol:/dev/sda2/@/.snapshots/1/snapshot: expecting a > device name > virt-sysprep: warning: cannot set random UUID on filesystem > btrfsvol:/dev/sda2/@/.snapshots type btrfs: set_uuid: set_uuid_stub: > btrfsvol:/dev/sda2/@/.snapshots: expecting a device name > virt-sysprep: warning: cannot set random UUID on filesystem > btrfsvol:/dev/sda2/@ type btrfs: set_uuid: set_uuid_stub: > btrfsvol:/dev/sda2/@: expecting a device name > [ 154.4] Performing "fs-uuids" ... > > ========================= > > I'd like to ask for your comments on fixing this. > Should we > 1. add a new command (guestfs_list_filesystems_devices) to return > only device-like filesystems? > 2. add something like guestfs_is_device which handles subvolumes on > host side? > NB: guestfs_is_blockdev also fails on stub > 3. allow guestfs_is_(blockdev|chardev|...) to check subvolumes on > host side? (maybe together with 2?) > 4. anything else? Number 4. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com Fedora Windows cross-compiler. Compile Windows programs, test, and build Windows installers. Over 100 libraries supported. http://fedoraproject.org/wiki/MinGW _______________________________________________ Libguestfs mailing list [email protected] https://www.redhat.com/mailman/listinfo/libguestfs
