On Tue, May 12, 2009 at 11:36:50AM +0200, Chris Lalancette wrote:
All, Even with Guido/Pritesh's recent changes to the vbox open routine, the auto-detection in libvirt is currently broken. What happens is that in src/libvirt.c:do_open(), at the start of the loop to auto-detect drivers, ret->uri is NULL. As each driver declines, it remains NULL. However, the very first thing the vboxOpen() routine does is:
if (conn->uri == NULL) { conn->uri = xmlParseURI(uid ? "vbox:///session" : "vbox:///system"); if (conn->uri == NULL) { return VIR_DRV_OPEN_ERROR; }
So, any driver that is trying to auto-probe after vboxOpen sees a conn->uri with a scheme of vbox and a path of system/session, and they all fail (including Qemu, which is what I'm mostly concerned with at the moment).
Please re-test with the patch I posted yesterday http://www.redhat.com/archives/libvir-list/2009-May/msg00198.html
In point of fact, this whole auto-detection thing is fragile. We got away with it before because the qemuOpen() routine bombs out before doing the whole conn->uri == NULL check, but in general, it's very easy for one buggy driver to mess up auto-detection for all drivers.
The general rule is that a driver should not set conn->uri to non-NULL until *after* it has determined that it can handle it. The problem here was that virtualbox driver was setting the uri to non-NULL, and only then seeing if virtalbox was available. My patch fixes that logic ordering bug Daniel -- |: Red Hat, Engineering, London -o- http://people.redhat.com/berrange/ :| |: http://libvirt.org -o- http://virt-manager.org -o- http://ovirt.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: GnuPG: 7D3B9505 -o- F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :|