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>
'-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>
Starting with QEMU-6.2 started accepting a JSON object as argument for
'-device' which will also become the only syntax considered stable by
qemu in the future.
Since libvirt was recently converted to generate the properties via JSON
to begin wit we can start using it on the commandline as well, by simply
enabling the QEMU_CAPS_DEVICE_JSON capability, which we do by probing
for the 'json-cli' feature flag of 'device_add'.
Normally a change which changes a commandline output should be happening
only after the impacted real-caps test files are forked in the version
preceding the change, but in this case it's not necessary as the logic
for generating the device properties stays identical and we just change
the output format (avoid conversion). Additionally we still have a lot
of tests validating the conversion to the old commandline options.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
virCommandToString has the possibility to return an already wrapped
string with better format than what we get from the test wrapper script.
The main advantage is that arguments for an option are always on the
same line which makes it more easy to see what changed in a diff and
prevents re-wrapping of the line if a wrapping point moves over the
threshold.
Additionally the used output is the same we have in the VM log file when
a VM is starting.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Base the detection on the presence of the 'secret' qom-type entry, which
isn't conditionally compiled in qemu.
All caps-based test now switch to using JSON for -object.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
The -audiodev argument is replacing the QEMU_AUDIO_DRV env variable (and
its relations).
Sadly we still have to use the SDL_AUDIODRIVER env variable because that
wasn't mapped into QAPI schema.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The preferred syntax for boolean options is to set the value "on" or
"off". QEMU 7.1.0 will deprecate the short format we currently use.
The long format has been supported with -chardev since at least 1.5.3,
so we don't need to check for it.
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
So far, Libvirt configures memory-backend-* for memory hotplug,
possibly NUMA nodes and in a few other cases. This patch
switches to constructing the memory-backend-* command line for
all cases. To keep ability to migrate guests a little hack is
used: the ID of the object is set to the one that QEMU uses
internally anyways. These IDs are stable (first started to appear
somewhere around v0.13.0-rc0~96) and can't change.
In fact, this patch does exactly what QEMU does internally. The
reason for moving the logic into Libvirt is that QEMU wants to
deprecate the old style of specifying memory.
So far, only x84_64 test cases are changed, because tests for
other architectures use older capabilities, which still lack the
QEMU_CAPS_MACHINE_MEMORY_BACKEND capability and they don't report
the RAM ID.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1836043
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
When starting a domain without a CPU model specified in the domain XML,
QEMU will choose a default one. Which is fine unless the domain gets
migrated to another host because libvirt doesn't perform any CPU ABI
checks and the virtual CPU provided by QEMU on the destination host can
differ from the one on the source host.
With QEMU 4.2.0 we can probe for the default CPU model used by QEMU for
a particular machine type and store it in the domain XML. This way the
chosen CPU model is more visible to users and libvirt will make sure
the guest will see the exact same CPU after migration.
Architecture specific notes
- aarch64: We only set the default CPU for TCG domains as KVM requires
explicit "-cpu host" to work.
- ppc64: The default CPU for KVM is "host" thanks to some hacks in QEMU,
we will translate the default model to the model corresponding to the
host CPU ("POWER8" on a Power8 host, "POWER9" on Power9 host, etc.).
This is not a problem as the corresponding CPU model is in fact an
alias for "host". This is probably not ideal, but it's not wrong and
the default virtual CPU configured by libvirt is the same QEMU would
use. TCG uses various CPU models depending on machine type and its
version.
- s390x: The default CPU for KVM is "host" while TCG defaults to "qemu".
- x86_64: The default CPU model (qemu64) is not runnable on any host
with KVM, but QEMU just disables unavailable features and starts
happily.
https://bugzilla.redhat.com/show_bug.cgi?id=1598151https://bugzilla.redhat.com/show_bug.cgi?id=1598162
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The latter is deprecated and will be removed soon. The advised
replacement is '-overcommit mem-lock=on|off'.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
By default, qemu user's home dir points to '/' which shouldn't be used
at all. We therefore pass the HOME variable from the current variable
iff not running as SUID, which means that for systemd we never set it.
This patch makes sure, that for system QEMU this is always set to
libDir/<driver>, session mode is left untouched.
Signed-off-by: Erik Skultety <eskultet@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
For session mode, only XDG_CACHE_HOME is set, because we want to remain
integrating with services in user session, but for system mode, this
would have become reading/writing to '/' which carries the obvious issue
with permissions (also, '/' is the wrong location in 99.9% cases anyway).
Signed-off-by: Erik Skultety <eskultet@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
There is a race condition when spawning QEMU where libvirt has spawned
QEMU but the monitor socket is not yet open. Libvirt has to repeatedly
try to connect() to QEMU's monitor until eventually it succeeds, or
times out. We use kill() to check if QEMU is still alive so we avoid
waiting a long time if QEMU exited, but having a timeout at all is still
unpleasant.
With QEMU 2.12 we can pass in a pre-opened FD for UNIX domain or TCP
sockets. If libvirt has called bind() and listen() on this FD, then we
have a guarantee that libvirt can immediately call connect() and
succeed without any race.
Although we only really care about this for the monitor socket and agent
socket, this patch does FD passing for all UNIX socket based character
devices since there appears to be no downside to it.
We don't do FD passing for TCP sockets, however, because it is only
possible to pass a single FD, while some hostnames may require listening
on multiple FDs to cover IPv4 and IPv6 concurrently.
Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Create a new vsock endpoint by opening /dev/vhost-vsock,
set the requested CID via ioctl (or assign a free one if auto='yes'),
pass the file descriptor to QEMU and build the command line.
https://bugzilla.redhat.com/show_bug.cgi?id=1291851
Signed-off-by: Ján Tomko <jtomko@redhat.com>
