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>
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>
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>
When guest has NUMA nodes and QEMU is new enough to report
default RAM ID then ideally we would use -numa memdev= combined
with memory-backend-* combo becasue -mem-path/-mem-prealloc/-numa
mem are deprecated. Well, there is one problem - the .memdev=
attribute is machine type dependent (just look at arguments of
virQEMUCapsGetMachineNumaMemSupported()) and to ensure backwards
compatibility we prefer -numa mem= over -numa memdev=.
But there was one corner case when -mem-prealloc was requested
but not generated on the cmd line. It all starts with
qemuBuildMemCommandLine() which generates just '-m XXX' and
because it sees defaultRAMid and guest NUMA nodes greater than
zero it does nothing more.
Then, qemuBuildNumaCommandLine() sees that -numa mem= is still
supported for given machine type and nothing else set
@needBackend thus qemuBuildMemPathStr() is called which output
-mem-prealloc only in a few cases assuming it was outputted
earlier.
Reported-by: Jing Qi <jinqi@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
This test shows a bug we have: even though the XML says:
<allocation mode='immediate'/>
there is no -mem-prealloc nor .prealloc=yes anywhere on the cmd
line. This will be fixed in the next commit.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
