Commit Graph

3 Commits

Author SHA1 Message Date
Peter Krempa
1a691fe1c8 qemu: capabilities: Re-enable JSON syntax for -device
Now that qemu fixed device unplug when JSON syntax is used with -device
we can re-enable the feature.

Since the old capability string representation is condemned by
suggesting filtering it as a workaround we must introduce a new string.
To achieve this the original capability position is renamed to
X_QEMU_CAPS_DEVICE_JSON_BROKEN_HOTPLUG and a new position with the
original name QEMU_CAPS_DEVICE_JSON is introduced to prevent us having
to change the rest of the code.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2022-01-17 09:26:17 +01:00
Peter Krempa
bd3d00babc qemu: Revert to using non-JSON commandline for -device
When -device is configured via JSON a bug [1] is triggered in qemu were
the DEVICE_DELETED event for the removal of the device frontend is no
longer delivered to libvirt. Without the DEVICE_DELETED event we don't
remove the corresponding entries in the VM XML.

Until qemu will be fixed we must stop using the JSON syntax for -device.

This patch removes the detection of the capability. The capability is
used only during startup of a fresh VM so we don't need to consider any
compaitibility steps for existing VMs.

For users who wish to use 'libvirt-7.9' and 'libvirt-7.10' with
'qemu-6.2' there are two possible workarounds:

 - filter out the 'device.json' qemu capability '/etc/libvirt/qemu.conf':

   capability_filters = [ "device.json" ]

 - filter out the 'device.json' qemu capability via qemu namespace XML:

   <domain type='kvm' xmlns:qemu='http://libvirt.org/schemas/domain/qemu/1.0'>
     [...]
     <qemu:capabilities>
       <qemu:del capability='device.json'/>
     </qemu:capabilities>
   </domain>

We must never again use the same capability name as we are now
instructing users to filter it as a workaround so once qemu is fixed
we'll need to pick a new capability value for it.

[1] https://bugzilla.redhat.com/show_bug.cgi?id=2036669

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2035237
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ani Sinha <ani@anisinha.ca>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2022-01-10 09:35:00 +01:00
Daniel P. Berrangé
e4e873e9b6 qemu: format sev-guest.kernel-hashes property
Set the kernel-hashes property on the sev-guest object if the config
asked for it explicitly. While QEMU machine types currently default to
having this setting off, it is not guaranteed to remain this way.

We can't assume that the QEMU capabilities were generated on an AMD host
with SEV, so we must force set the QEMU_CAPS_SEV_GUEST. This also means
that the 'sev' info in the qemuCaps struct might be NULL, but this is
harmless from POV of testing the CLI generator.

Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2021-12-16 18:10:33 +00:00