For me it's the mtab entry for tracefs on a non-existing mount point in /var/lib/ureadahead/debugfs/tracing that is causing problems. It does affect VMware snapshots when quiescing is required too.
Since it's a different entry then in this post I opened a new bug report in #1659684 -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to mountall in Ubuntu. https://bugs.launchpad.net/bugs/499773 Title: Race with ureadahead can mean that /var/lib/ureadahead/debugfs appears in /etc/mtab Status in mountall package in Ubuntu: Triaged Bug description: When the system is booted, the mountall process may notice a temporarily-mounted file system at /var/lib/ureadahead/debugfs and record that fact in /etc/mtab. Later in the boot process, this file system is unmounted, but mountall doesn't record unmounts, so it never "forgets" this path when it's unmounted. Mountall should if necessary remove this mount from mtab. To confirm on your system that it is indeed not really mounted, look for it in /proc/self/mountinfo Otherwise this may be due to a crash of the ureadahead process during boot. ---- original report ---- Binary package hint: ureadahead $ mount /dev/sda1 on / type ext3 (rw,relatime,errors=remount-ro) proc on /proc type proc (rw) none on /sys type sysfs (rw,noexec,nosuid,nodev) none on /sys/fs/fuse/connections type fusectl (rw) none on /sys/kernel/debug type debugfs (rw) none on /sys/kernel/security type securityfs (rw) udev on /dev type tmpfs (rw,mode=0755) none on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=0620) none on /dev/shm type tmpfs (rw,nosuid,nodev) none on /var/run type tmpfs (rw,nosuid,mode=0755) none on /var/lock type tmpfs (rw,noexec,nosuid,nodev) none on /lib/init/rw type tmpfs (rw,nosuid,mode=0755) none on /var/lib/ureadahead/debugfs type debugfs (rw) /dev/sda6 on /home type ext4 (rw,relatime) binfmt_misc on /proc/sys/fs/binfmt_misc type binfmt_misc (rw,noexec,nosuid,nodev) gvfs-fuse-daemon on /home/hildeb/.gvfs type fuse.gvfs-fuse-daemon (rw,nosuid,nodev,user=hildeb) /var/lib/ureadahead/debugfs is left lingering around. It's use is somewhat limited, since most Ubuntu users are not kernel developers -- if it's used as intended: http://kerneltrap.org/node/4394 ProblemType: Bug Architecture: amd64 Date: Wed Dec 23 11:04:11 2009 DistroRelease: Ubuntu 9.10 NonfreeKernelModules: nvidia Package: ureadahead 0.90.3-2 ProcEnviron: LANG=en_US.UTF-8 SHELL=/bin/bash ProcVersionSignature: Ubuntu 2.6.31-17.54-generic SourcePackage: ureadahead Uname: Linux 2.6.31-17-generic x86_64 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/mountall/+bug/499773/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
