Re: [libvirt] [PATCH] fix deadlock when qemu cannot start

Quoting Daniel Veillard (veillard(a)redhat.com): > On Fri, Mar 16, 2012 at 02:37:42PM +0800, Wen Congyang wrote: > > When qemu cannot start, we may call qemuProcessStop() twice. > > We have check whether the vm is running at the beginning of > > qemuProcessStop() to avoid libvirt deadlock. We call > > qemuProcessStop() with driver and vm locked. It seems that > > we can avoid libvirt deadlock. But unfortunately we may > > unlock driver and vm in the function qemuProcessKill() while > > vm->def->id is not -1. So qemuProcessStop() will be run twice, > > and monitor will be freed unexpectedly. So we should set > > vm->def->id to -1 at the beginning of qemuProcessStop(). Oh, uh, Huh. This seems like it could be responsible for what I was reporting a few days ago (*1). I spent most of yesterday trying to track it down, only to finally realize that the QemuProcessStart would silently die at various places. So i was getting ready to send an email postulating that what's happening is that a virsh list starts, then a virsh start starts, and when the virsh list ends it somehow causes the virsh start to be killed. I'll test and see if this patch fixes it.