Commit Graph

13 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
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
Peter Krempa
c9b13e0557 qemu: Use JSON directly for '-device'
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>
2021-10-18 14:00:58 +02:00
Peter Krempa
0046e0b1c2 qemuxml2argvtest: Use internal wrapping of command line arguments
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>
2021-04-12 15:55:10 +02:00
Peter Krempa
f763b6e439 qemu: capabilities: Enable detection of QEMU_CAPS_OBJECT_QAPIFIED
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>
2021-03-23 14:06:31 +01:00
Daniel P. Berrangé
d96fb5cb31 qemu: add support for generating -audiodev arguments
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>
2021-03-09 22:58:36 +00:00
Daniel P. Berrangé
43c9c0859f qemu: use long on|off syntax for -chardev boolean option values
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>
2021-02-16 12:38:20 +00:00
Jiri Denemark
4901314d0d cpu_map: Remove intel-pt from x86 CPU models
As explained in QEMU commit 4c257911dcc7c4189768e9651755c849ce9db4e8
intel-pt features should never be included in the CPU models as it was
not supported by KVM back then and even once it started to be supported,
users have to enable it by passing pt_mode=1 parameter to kvm_intel
module. The Icelake-* CPU models with intel-pt included were added to
QEMU 3.1.0 and removed right in the following 4.0.0 release (and even in
3.1.1 maintenance release).

In libvirt 6.10.0 I introduced 'removed' attribute for features included
in our CPU model definitions which we can use to drop intel-pt from
Icelake-* CPU models. Back then I explained we can safely do so only for
features which could never be enabled, which is not the case of intel-pt.

Theoretically, it could be possible to create an environment in which
QEMU would enable intel-pt without asking for it explicitly: it would
need to use a new enough kernel (not available at the time of QEMU
3.1.0) and pt_mode KVM parameter in combination with QEMU 3.1.0 running
a domain with q35 machine type and all that on a CPU which didn't really
exist at that time.

Migrating such domain to a host with newer SW stack including libvirt
with this patch applied would result in incompatible guest ABI (the
virtual CPU would lose intel-pt). However, QEMU changed its CPU models
unconditionally and thus migration would not work even without this
patch. That said, it is safe to follow QEMU and remove the feature from
Icelake-* CPU models in our cpu_map.

https://bugzilla.redhat.com/show_bug.cgi?id=1853972

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Tim Wiederhake <twiederh@redhat.com>
2021-01-26 15:44:50 +01:00
Michal Privoznik
88957116c9 qemu: Use memory-backend-* for regular guest memory
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>
2020-10-01 12:06:22 +02:00
Jiri Denemark
ac34e14159 qemu: Drop disabled CPU features unknown to QEMU
When a CPU definition wants to explicitly disable some features that are
unknown to QEMU, we can safely drop them from the definition before
starting QEMU. Naturally QEMU won't enable such features implicitly.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2019-11-12 20:14:16 +01:00
Jiri Denemark
ae793ecbcb qemuxml2*test: Add tests for Icelake-Server,-pconfig
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2019-11-12 20:14:15 +01:00