I did a little more testing. root@virt:~# uname -r 3.13.0-32-generic
Actually the hanging seams to happen only when the overlayfs parts are on the logical volume being the snapshot source. Let's say /opt is a logical volume in the volume group virt. Case 1 (hanging): mkdir /opt/test/ cd /opt/test/ mkdir upper lower file_system touch lower/bla.dat mount -t overlayfs -o lowerdir=/opt/test/lower,upperdir=/opt/test/upper overlayfs /opt/test/file_system lvcreate -s -L 5G /dev/virt/opt -n vm_backup -> Hang (see previous posts) Case 2 (not hanging): mkdir /opt/test/ lvcreate -n test -L10G virt mkfs.xfs /dev/virt/test mount /dev/virt/test /opt/test cd /opt/test/ mkdir upper lower file_system touch lower/bla.dat mount -t overlayfs -o lowerdir=/opt/test/lower,upperdir=/opt/test/upper overlayfs /opt/test/file_system lvcreate -s -L 5G /dev/virt/opt -n vm_backup Snapshot created even through the overlayfs is in use (but on a different volume). So the work around for the moment is to use two types of logical volumes : 1 one type for use with overlayfs where one has to make sure that no one ever takes a snapshot of (at least until this bug is fixed.) 2. one type where overlayfs never gets used but where snapshots can be taken from. May be this helps someone running into this issue. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1328595 Title: lvcreate -s hangs when overlayfs is in use Status in “linux” package in Ubuntu: Confirmed Bug description: I am using xbuntu 14.04 LTS in combination with KVM, lxc, logical volumes and overlayfs. After I started using overlayfs i realized that my backup based on LVM snapshots made the system "go mad". As described in the manual I tried the kernel from 13.10 (3.11.0-xx) with the same result. A test against main line does not help, since it does not include the overlayfs support. I tested the behaviour on a server as well as in a VirtualBox environment with the same result: lvcreate -s -n backup -L512M /dev/VG/NAME hangs and does not come back. This issue is easy reproducable: sudo mkdir /mnt/test /mnt/delta sudo mount -t overlayfs -o lowerdir=/usr,upperdir=/mnt/delta overlayfs /mnt/test sudo lvcreate -s -n backup -L512M /dev/xubuntu-vg/root -> Hang df@feretti-virt:~$ uname -r 3.13.0-29-generic df@feretti-virt:~$ cat /proc/version_signature Ubuntu 3.13.0-29.53-generic 3.13.11.2 ProblemType: Bug DistroRelease: Ubuntu 14.04 Package: linux-image-3.13.0-29-generic 3.13.0-29.53 ProcVersionSignature: Ubuntu 3.13.0-29.53-generic 3.13.11.2 Uname: Linux 3.13.0-29-generic x86_64 ApportVersion: 2.14.1-0ubuntu3.2 Architecture: amd64 AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/by-path', '/dev/snd/controlC0', '/dev/snd/pcmC0D0c', '/dev/snd/pcmC0D0p', '/dev/snd/pcmC0D1c', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1: Date: Tue Jun 10 18:02:13 2014 HibernationDevice: RESUME=UUID=6e68761a-6768-4e19-9c4e-f188538d6068 InstallationDate: Installed on 2014-02-18 (112 days ago) InstallationMedia: Xubuntu 13.10 "Saucy Salamander" - Release amd64 (20131016) Lsusb: Bus 001 Device 002: ID 80ee:0021 VirtualBox USB Tablet Bus 001 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub MachineType: innotek GmbH VirtualBox ProcEnviron: TERM=xterm PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=de_DE.UTF-8 SHELL=/bin/bash ProcFB: 0 VESA VGA ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-3.13.0-29-generic root=/dev/mapper/xubuntu--vg-root ro quiet splash vt.handoff=7 PulseList: Error: command ['pacmd', 'list'] failed with exit code 1: No PulseAudio daemon running, or not running as session daemon. RelatedPackageVersions: linux-restricted-modules-3.13.0-29-generic N/A linux-backports-modules-3.13.0-29-generic N/A linux-firmware 1.127.2 RfKill: SourcePackage: linux UpgradeStatus: Upgraded to trusty on 2014-04-22 (49 days ago) dmi.bios.date: 12/01/2006 dmi.bios.vendor: innotek GmbH dmi.bios.version: VirtualBox dmi.board.name: VirtualBox dmi.board.vendor: Oracle Corporation dmi.board.version: 1.2 dmi.chassis.type: 1 dmi.chassis.vendor: Oracle Corporation dmi.modalias: dmi:bvninnotekGmbH:bvrVirtualBox:bd12/01/2006:svninnotekGmbH:pnVirtualBox:pvr1.2:rvnOracleCorporation:rnVirtualBox:rvr1.2:cvnOracleCorporation:ct1:cvr: dmi.product.name: VirtualBox dmi.product.version: 1.2 dmi.sys.vendor: innotek GmbH To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1328595/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
