Re: [libvirt] [PATCH 2/5] daemonize qemu processes

On Mon, Dec 15, 2008 at 11:21:20AM +0000, Daniel P. Berrange wrote: > On Fri, Dec 12, 2008 at 07:26:32PM +0100, Guido G?nther wrote: > > + if (kill(vm->pid, SIGTERM) < 0) > > + qemudLog(QEMUD_ERROR, _("Failed to send SIGTERM to %s (%d): %s\n"), > > + vm->def->name, vm->pid, strerror(errno)); > > We should add a guard around all the kill() statements for > > if (vm->pid > 1) > kill.. > > One of the bugs I found when doing the LXC/UML drivers is that when relying > on an external PID file, some things can go wrong in unexpected ways that > just don't happen when getting the PID straight back from fork. This often > ended up with vm->pid being -1, 0 with horrific results - > > "If pid equals -1, then sig is sent to every process for which the calling > process has permission to send signals, except for process 1 (init)" > > Yes, I killed every single process on my dev machine several times before > discovering this isues :-) This call for an utility function int virKillProcess(pid_t pid, int sig) call checking for this, could also help on debugging/logging