[Pkg-libvirt-maintainers] Bug#961575: Regression with QEMU 5.0: Host does not support any virtualization options

[Martin Pitt]

Package: libvirt-daemon-driver-qemu
Version: 6.0.0-6

In our latest Cockpit CI image refresh of debian-testing [1], all libvirt/QEMU
tests are broken:

| > warning: error: failed to get emulator capabilities
| error: invalid argument: unable to find any emulator to serve 'x86_64' architecture
| ERROR    Host does not support any virtualization options 

libvirt version did not change (6.0.0-6), but QEMU updated from 4.2 to 5.0.
libvirt does not seem to get along with this:

| admin at debian:~$ virt-install -n test1 --memory 1024 --disk none --pxe --debug
| [Tue, 26 May 2020 08:35:51 virt-install 33417] DEBUG (cli:208) Launched with command line: /usr/share/virt-manager/virt-install -n test1 --memory 1024 --disk none --pxe --debug
| [Tue, 26 May 2020 08:35:51 virt-install 33417] DEBUG (virt-install:207) Distilled --network options: ['default']
| [Tue, 26 May 2020 08:35:51 virt-install 33417] DEBUG (virt-install:139) Distilled --disk options: ['none']
| [Tue, 26 May 2020 08:35:51 virt-install 33417] DEBUG (cli:224) Requesting libvirt URI default
| [Tue, 26 May 2020 08:35:51 virt-install 33417] DEBUG (cli:227) Received libvirt URI qemu:///session
| [Tue, 26 May 2020 08:35:52 virt-install 33417] DEBUG (cli:263)   File "/usr/share/virt-manager/virt-install", line 1012, in <module>
|     fail(main_e)
|   File "/usr/share/virt-manager/virtinst/cli.py", line 263, in fail
|     log.debug("".join(traceback.format_stack()))
| 
| [Tue, 26 May 2020 08:35:52 virt-install 33417] ERROR (cli:264) Host does not support any virtualization options
| [Tue, 26 May 2020 08:35:52 virt-install 33417] DEBUG (cli:266)
| Traceback (most recent call last):
|   File "/usr/share/virt-manager/virt-install", line 1005, in <module>
|     sys.exit(main())
|   File "/usr/share/virt-manager/virt-install", line 993, in main
|     guest, installer = build_guest_instance(conn, options)
|   File "/usr/share/virt-manager/virt-install", line 547, in build_guest_instance
|     guest.set_capabilities_defaults()
|   File "/usr/share/virt-manager/virtinst/guest.py", line 681, in set_capabilities_defaults
|     capsinfo = self.lookup_capsinfo()
|   File "/usr/share/virt-manager/virtinst/guest.py", line 670, in lookup_capsinfo
|     self._capsinfo = self.conn.caps.guest_lookup(
|   File "/usr/share/virt-manager/virtinst/capabilities.py", line 300, in guest_lookup
|     raise ValueError(_("Host does not support %(virttype)s %(arch)s") %
| ValueError: Host does not support any virtualization options

Note that this is not specific to --pxe, it's just the absolutely cheapest way
that I know of to create a domain and start QEMU.


This may be related to a regression in QEMU itself:

| $ admin at debian:~$ qemu-system-x86_64 -nographic
| Could not allocate dynamic translator buffer

I filed that as https://bugs.debian.org/961574

Thanks,

Martin

[1] https://github.com/cockpit-project/bots/pull/890