So this is interesting. Debian's /lib/systemd/systemd works, but the hang happens under upstart too (where that binary isn't being used!). So it must be something which we change in Ubuntu's systemd, but conceptually also do for upstart/cgmanager. The first candidate that I see is to put processes into all cgroups for session LXC, I'll verify that.
-- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to systemd in Ubuntu. https://bugs.launchpad.net/bugs/1398859 Title: unmounting NTFS causes mount.ntfs process to get stuck in eternal kernel deep sleep Status in systemd package in Ubuntu: Triaged Bug description: Since Mid-November the udisks2 test (https://jenkins.qa.ubuntu.com/job /vivid-adt-udisks2/? shows it happened between Nov 13 and 19) exhibits a regression with NTFS: Unmounting causes the ntfs-3g process to go into kernel deep sleep and umount hangs forever. This can be reproduced with sudo apt install ntfs-3g sudo modprobe scsi_debug # check dmesg which drive this created; e. g. /dev/sda sudo mkntfs -F /dev/sda sudo mount /dev/sda /mnt Now you have a process which is happy: root 12821 0.0 0.0 15272 1948 ? Ss 15:49 0:00 /sbin/mount.ntfs /dev/sda /mnt -o rw You can work with /mnt, edit files, etc. But now unmount: sudo umount /mnt This never returns, and the process goes into uninterruptible kernel sleep ("D"): root 12928 0.0 0.0 15272 1948 ? Ds 15:55 0:00 /sbin/mount.ntfs /dev/sda /mnt -o rw The strace for the umount until the hang is ubuntu@autopkgtest:~$ sudo strace -vvtts1024 -p 12928 Process 12928 attached 15:56:17.938299 read(4, "0\0\0\0\2\0\0\0\2\0\0\0\0\0\0\0\1\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\1\0\0\0\0\0\0\0", 135168) = 48 15:56:22.338931 read(4, "(\0\0\0&\0\0\0\3\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", 135168) = 40 15:56:22.339637 sendto(5, "<29>Dec 3 15:56:22 ntfs-3g[12928]: Unmounting /dev/sda ()\n", 59, MSG_NOSIGNAL, NULL, 0) = 59 15:56:22.340509 fsync(3) = 0 15:56:22.341188 fcntl(3, F_SETLK, {type=F_UNLCK, whence=SEEK_SET, start=0, len=0}) = 0 15:56:22.341759 close(3 ProblemType: Bug DistroRelease: Ubuntu 15.04 Package: ntfs-3g 1:2013.1.13AR.1-2ubuntu3 ProcVersionSignature: Ubuntu 3.16.0-25.33-generic 3.16.7 Uname: Linux 3.16.0-25-generic x86_64 ApportVersion: 2.15-0ubuntu1 Architecture: amd64 CurrentDesktop: Unity Date: Wed Dec 3 15:48:12 2014 EcryptfsInUse: Yes InstallationDate: Installed on 2014-11-20 (13 days ago) InstallationMedia: Ubuntu 15.04 "Vivid Vervet" - Alpha amd64 (20141119) SourcePackage: ntfs-3g UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1398859/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
