[Buildd-tools-devel] Bug#520713: Bug#520713: init script start hangs

[Roger Leigh]

On Sun, Mar 22, 2009 at 10:54:52AM +0100, Peter Palfrader wrote:
> 
> Since the init script is run in rcS/75, before there is an sshd or
> anything else useful this breaks the system completely, requiring remote
> hands from a local person if no OOB access is available.
> 
> goetz:~# sh -x /etc/init.d/schroot start
> ...
> Recovering schroot sessions:+ return
> ++ /usr/bin/schroot --all-sessions --list --quiet
> + for chroot in '`$SCHROOT --all-sessions --list --quiet`'
> + /usr/bin/schroot --chroot=sid-alpha-sbuild-7855514e-e68e-40e3-8198-61366cd44074 --recover-session
> [just hangs here]
> 
> It appears to be stuck in some kind of futex thing:
> 
> weasel at goetz:~$ sudo strace -p 11214 2>&1 | head
> Process 11214 attached - interrupt to quit
> futex(0x120140158, FUTEX_WAIT_PRIVATE, 2, NULL) = -1 EAGAIN (Resource temporarily unavailable)

Are there any other child processes around on the system?

In the schroot code, we don't use futexes directly.  The code is
single-threaded.  The only remotely related thing we use are
fcntl file locks and signals, which have short timeouts.

It could be waiting on a child process such as a setup script to
complete.  Knowing exactly what's stuck would help greatly.


Regards,
Roger

-- 
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