[Pkg-utopia-maintainers] Bug#721303: udisks: breaks LVM and deadlocks LVM related IO to system [SEC=UNCLASSIFIED]

[Tim Connors]

Package: udisks
Version: 1.0.4-7
Severity: critical
Justification: breaks unrelated software

lvm snapshot removal has been broken in debian for a few years now.
lvremove has a good chance at any moment to deadlock IO to a box.  If
you happen to be lucky enough to have dmsetup still in cache, you
might be able to resume the device, but more often than not, you
simply have no choice but to reboot.  Which is kinda bad.

/lib/udev/rules.d/80-udisks.rules has the following line in it:
KERNEL=="dm-*", OPTIONS+="watch"

>From https://www.redhat.com/archives/linux-lvm/2010-August/msg00038.html
https://bugzilla.redhat.com/show_bug.cgi?id=577798#c5

we see that you can remove that line, and have reliable lvm again.  In
fact, rhel6 has a similar kernel to debian wheezy, and has commented
that line out all together:

# Make udevd synthesize a 'change' uevent when last opener of a rw-fd closes the fd - this
# should be part of the device-mapper rules
#
# Disabled as per #738479
# KERNEL=="dm-*", OPTIONS+="watch"

(unfortunately we don't have permission to view rhbz#738479, but I
suspect it's just a clone of the fc13 bug 577798)

Since I believe this bug directly causes debian bugs: 592250 549691
618016 and probably dozens of others, can we just remove that line in
/lib/udev/rules.d/80-udisks.rules like they have in RHEL6 until the
real race condition is discovered?  Marking as critical, because
udisks seems to be pulled in by default on debian, seems to be
unnecessary, and most definitely breaks unrelated parts of the system
(forced reboots on production systems are bad, mmmkay?)





-- System Information:
Debian Release: 7.1
  APT prefers stable-updates
  APT policy: (500, 'stable-updates'), (500, 'stable'), (5, 'testing'), (1, 'unstable')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 3.2.0-4-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_AU.UTF-8, LC_CTYPE=en_AU.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages udisks depends on:
ii  dbus                   1.6.8-1+deb7u1
ii  libatasmart4           0.19-1
ii  libc6                  2.13-38
ii  libdbus-1-3            1.6.8-1+deb7u1
ii  libdbus-glib-1-2       0.100.2-1
ii  libdevmapper1.02.1     2:1.02.74-7
ii  libglib2.0-0           2.33.12+really2.32.4-5
ii  libgudev-1.0-0         175-7.2
ii  liblvm2app2.2          2.02.95-7
ii  libparted0debian1      2.3-12
ii  libpolkit-gobject-1-0  0.105-3
ii  libsgutils2-2          1.33-1
ii  libudev0               175-7.2
ii  udev                   175-7.2

Versions of packages udisks recommends:
ii  cryptsetup-bin  2:1.4.3-4
ii  dosfstools      3.0.13-1
ii  eject           2.1.5+deb1+cvs20081104-13
ii  hdparm          9.39-1+b1
ii  ntfs-3g         1:2012.1.15AR.5-2.1
ii  policykit-1     0.105-3

Versions of packages udisks suggests:
ii  mdadm          3.2.5-5
pn  reiserfsprogs  <none>
pn  xfsprogs       <none>