On Wed, Mar 16, 2011 at 02:54:28PM +0800, Wen Congyang wrote: > Steps to reproduce this bug: > # virsh qemu-monitor-command domain 'cpu_set 2 online' --hmp > The domain has 2 cpus, and we try to set the third cpu online. > The qemu crashes, and this command will hang. > > The reason is that the refs is not 1 when we unwatch the monitor. > We lock the monitor, but we do not unlock it. So virCondWait() > will be blocked. > > Signed-off-by: Wen Congyang <wency@xxxxxxxxxxxxxx> > > --- > src/qemu/qemu_monitor.c | 3 ++- > 1 files changed, 2 insertions(+), 1 deletions(-) > > diff --git a/src/qemu/qemu_monitor.c b/src/qemu/qemu_monitor.c > index da38096..dc08594 100644 > --- a/src/qemu/qemu_monitor.c > +++ b/src/qemu/qemu_monitor.c > @@ -239,7 +239,8 @@ qemuMonitorUnwatch(void *monitor) > qemuMonitorPtr mon = monitor; > > qemuMonitorLock(mon); > - qemuMonitorUnref(mon); > + if (qemuMonitorUnref(mon) > 0) > + qemuMonitorUnlock(mon); > } ACK We should probably annotate qemuMonitorUnref() (and similar functions) with ATTRIBUTE_RETURN_CHECK too Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :| -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list