Olivier Langlois <olivier@xxxxxxxxxxxxxx> writes: > On Mon, 2022-01-10 at 15:11 -0600, Eric W. Biederman wrote: >> >> >> I have been able to confirm that changing wait_event_interruptible to >> wait_event_killable was the culprit. Something about the way >> systemd-coredump handles coredumps is not compatible with >> wait_event_killable. > > This is my experience too that systemd-coredump is doing something > unexpected. When I tested the patch: > https://lore.kernel.org/lkml/cover.1629655338.git.olivier@xxxxxxxxxxxxxx/ > > to make sure that the patch worked, sending coredumps to systemd- > coredump was making systemd-coredump, well, core dump... Not very > useful... Oh. Wow.... > Sending the dumps through a pipe to anything else than systemd-coredump > was working fine. Interesting. I need to read through the pipe code and see how all of that works. For writing directly to disk only ignoring killable interruptions are the usual semantics. Ordinary pipe code has different semantics, and I suspect that is what is tripping things up. As for systemd-coredump it does whatever it does and I suspect some versions of systemd-coredump are simply not robust if a coredump stops unexpectedly. The good news is the pipe code is simple enough, it will be possible to completely read through that code. Eric