[Bug 1696970] Re: softlockup DoS causes systemd-journald.service to abort with SIGABORT

[Dimitri John Ledkov]

I see more chatter about journald aborting upstream and on the mailing
lists. Imho, just because journald was not scheduled to run kind of
means that maybe it has too low of a priority, or the system is
overloaded. It does not show that journald is actually at fault here,
and/or failing. Imho, one shouldn't be killing journald, when it is
otherwise obviously operating fine (aka waiting to be run).

I'm concerned as to why there is a watchdog on journald now. It should
be rocksolid, and either work or crash, there is no need to crash it on
a fixed schedule just because.

** Also affects: systemd (Ubuntu Bionic)
   Importance: High
     Assignee: Balint Reczey (rbalint)
       Status: Opinion

** Changed in: systemd (Ubuntu Bionic)
       Status: Opinion => Confirmed

** Changed in: systemd (Ubuntu Bionic)
     Assignee: Balint Reczey (rbalint) => (unassigned)

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to systemd in Ubuntu.
https://bugs.launchpad.net/bugs/1696970

Title:
  softlockup DoS causes systemd-journald.service to abort with SIGABORT

Status in systemd package in Ubuntu:
  Confirmed
Status in systemd source package in Artful:
  Opinion
Status in systemd source package in Bionic:
  Confirmed

Bug description:
  I was running the new stress-ng softlockup stressor and observed that
  systemd-journald gets killed with an abort and this corrupts the
  systemd journal.

  How to reproduce:

  git clone git://kernel.ubuntu.com/cking/stress-ng
  cd stress-ng
  make clean; make

  sudo ./stress-ng --softlockup 0 -t 360 -v

  ..and wait for 360 seconds.  dmesg shows the following, 100%
  reproduceable:

  
  [  875.310331] systemd[1]: systemd-timesyncd.service: Watchdog timeout (limit 3min)!
  [  875.310740] systemd[1]: systemd-timesyncd.service: Killing process 574 (systemd-timesyn) with signal SIGABRT.
  [  875.327289] systemd[1]: systemd-timesyncd.service: Main process exited, code=killed, status=6/ABRT
  [  875.327666] systemd[1]: systemd-timesyncd.service: Unit entered failed state.
  [  875.327686] systemd[1]: systemd-timesyncd.service: Failed with result 'watchdog'.
  [  875.327917] systemd[1]: systemd-timesyncd.service: Service has no hold-off time, scheduling restart.
  [  875.327954] systemd[1]: Stopped Network Time Synchronization.
  [  875.328845] systemd[1]: Starting Network Time Synchronization...
  [  875.525071] systemd[1]: Started Network Time Synchronization.
  [  875.539619] systemd[1]: systemd-journald.service: Main process exited, code=dumped, status=6/ABRT
  [  875.544257] systemd-journald[5214]: File /run/log/journal/440e485e550040e3b93b66b2faae8525/system.journal corrupted or uncleanly shut down, renaming and replacing.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1696970/+subscriptions