Commit Graph

6 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
Michal Privoznik
c1355849e4 qemu_command: do use host-nodes for system memory
After previous commit, it's no longer possible to change nodeset
for strict numatune. Therefore, we can start generating
host-nodes onto command line again.

This partially reverts d73265af6e.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
2021-12-17 13:21:55 +01:00
Michal Privoznik
d20ebdda28 qemu: Switch to -accel
We currently use -machine accel=XXX which is just a syntax sugar
for -accel XXX. The former doesn't allow specifying arguments for
accelerator, because all arguments passed to -machine are
treated as arguments of machine itself.

The -accel argument was introduced in QEMU commit
v2.9.0-rc0~70^2~19 and since our minimum required version is
newer (2.11.0) we can safely assume its existence and use it
without any capability.

Resolves: https://gitlab.com/libvirt/libvirt/-/issues/233
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Tested-by: Kashyap Chamarthy <kchamart@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
2021-11-22 13:06:54 +01:00
Peter Krempa
279c64dccb qemu: command: Use JSON for parameters of -audiodev
'-audiodev' as a modern implementation based on QAPI already takes JSON
as the argument. Convert our code to use it directly.

The declaration of the QAPI types can be found in
'qemu.git/qapi/audio.json'.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2021-11-17 12:04:11 +01:00
Pavel Hrdina
d73265af6e qemu_command: do not use host-nodes for system memory
Commit 88957116c9 switched to use
memory-backend-* for regular VM memory as well. That change indirectly
started using 'host-nodes' for system memory which results in QEMU
calling mbind() to bind the system memory to specific NUMA node if the
VM XML contains the configuration similar to this:

  ...
  <numatune>
    <memory mode='strict' nodeset='0'/>
  </numatune>
  ...

Once the VM was started with that configuration it was no longer
possible to change the memory NUMA nodeset.

Fixes: 677c90cc1d
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2021-11-10 11:17:44 +01:00