Peter Krempa [Tue, 18 Jan 2022 15:19:03 +0000 (16:19 +0100)]
qemuBuildDeviceVideoCmd: Always assume support for 'max_outputs' property
Both the QXL video device and 'virtio' video device support
'max_outputs' in all qemu versions libvirt supports. This means we no
longer have to check the QEMU_CAPS_QXL_MAX_OUTPUTS and
QEMU_CAPS_VIRTIO_GPU_MAX_OUTPUTS capabilities.
Signed-off-by: Peter Krempa <pkrempa@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com>
Peter Krempa [Tue, 18 Jan 2022 14:43:42 +0000 (15:43 +0100)]
virDomainDeviceInfoParseXML: Reject '0' value for ACPI index
Value of '0' is treated equivalently to when it's not provided by the
user. Reject an explicit '0' provided by the user as it would get
ignored.
In this rare case we can make the XML parser more strict, as libvirt
would never format the '<acpi/>' element if the index is '0' thus there
are no libvirt-generated XMLs we'd not load back, as of such this is
identical to rejecting it in the validation phase.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2037146 Signed-off-by: Peter Krempa <pkrempa@redhat.com> Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Michal Privoznik [Mon, 10 Jan 2022 11:59:29 +0000 (12:59 +0100)]
virsh-network: Don't check for virshXXXTypeFromString() >= VIR_XXX_LAST
They way our VIR_ENUM_IMPL() and virXXXTypeFromString() work is
that for any string that's not recognized a negative one is
returned. And, since VIR_XXX_LAST is passed to VIR_ENUM_IMPL() we
can be sure that all enum members are covered. Therefore, there
is no way that virXXXTypeFromString() can return a value that's
bigger or equal to VIR_XXX_LAST.
I've noticed two places where such comparison was made, both in
cmdNetworkUpdate(). Drop them.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> Reviewed-by: Andrea Bolognani <abologna@redhat.com>
We're currently passing '0' which leaves the syslog facility
unset. Since we're passing an explicit facility for syslog
when using journald, it makes sense to be explicit when
using syslog directly too.
Reviewed-by: Ján Tomko <jtomko@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
used the LOG_nnn constants from the syslog header without realizing
that these values have a bit-shift applied. While Linux defines a
LOG_FAC() macros to undo the bit-shift this doesn't appear to be
standardized. So the safe thing is to just use the raw value since
these values are fixed by RFC 5424.
Reviewed-by: Ján Tomko <jtomko@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Tim Wiederhake [Thu, 13 Jan 2022 16:53:25 +0000 (17:53 +0100)]
docs: coding-style: One variable declaration per line
This was not mentioned before.
Signed-off-by: Tim Wiederhake <twiederh@redhat.com> Reviewed-by: Peter Krempa <pkrempa@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com> Reviewed-by: Andrea Bolognani <abologna@redhat.com> Reviewed-by: Michal Privoznik <mprivozn@redhat.com> Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
Signed-off-by: Tim Wiederhake <twiederh@redhat.com> Reviewed-by: Peter Krempa <pkrempa@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com> Reviewed-by: Andrea Bolognani <abologna@redhat.com> Reviewed-by: Michal Privoznik <mprivozn@redhat.com> Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
Tim Wiederhake [Wed, 19 Jan 2022 10:08:13 +0000 (11:08 +0100)]
manpages: libvirt-guests: Fix typos
Signed-off-by: Tim Wiederhake <twiederh@redhat.com> Reviewed-by: Andrea Bolognani <abologna@redhat.com> Reviewed-by: Erik Skultety <eskultet@redhat.com>
Ján Tomko [Mon, 17 Jan 2022 16:20:42 +0000 (17:20 +0100)]
util: openvswitch: split out virNetDevOpenvswitchInterfaceSetRxQos
The virNetDevOpenvswitchInterfaceSetQos function is uneven
because setting the Rx Qos is open-coded, while clearing it
is sepearated in another function.
Separate the setting too.
Signed-off-by: Ján Tomko <jtomko@redhat.com> Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Ján Tomko [Mon, 17 Jan 2022 16:13:12 +0000 (17:13 +0100)]
util: openvswitch: split out virNetDevOpenvswitchInterfaceSetTxQos
The virNetDevOpenvswitchInterfaceSetQos function is uneven
because setting the Tx Qos is open-coded, while clearing it
is sepearated in another function.
Separate the setting too.
Signed-off-by: Ján Tomko <jtomko@redhat.com> Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Andrea Bolognani [Mon, 17 Jan 2022 16:31:52 +0000 (17:31 +0100)]
util: Stop storing dnsmasq version
We don't do anything with it after checking that it satisfies our
requirements and don't provide a way for users of the module to
access it, so carrying it around is pointless.
Signed-off-by: Andrea Bolognani <abologna@redhat.com> Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Andrea Bolognani [Mon, 17 Jan 2022 16:27:52 +0000 (17:27 +0100)]
spec: Drop BuildRequires on dnsmasq
It's been an optional build time dependency for a long time, so
if Meson couldn't find it the only consequence was that libvirt
would look for it at runtime instead, which is what we are doing
for most of our non-library dependencies anyway.
Since 5c98d1cee0be we've stopped even looking for it at build
time, so there's no point in having it installed in the build
environment.
Signed-off-by: Andrea Bolognani <abologna@redhat.com> Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Michal Privoznik [Wed, 12 Jan 2022 04:58:39 +0000 (05:58 +0100)]
virdnsmasq: Join dnsmasqCapsNewEmpty() and dnsmasqCapsNewFromBinary()
After previous cleanups, there's just one caller of
dnsmasqCapsNewEmpty() and it is dnsmasqCapsNewFromBinary().
And the former is pretty short. Therefore, it is not necessary
for the code to live in two separate functions. Dissolve the
former in the latter.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Michal Privoznik [Mon, 17 Jan 2022 12:14:45 +0000 (13:14 +0100)]
networkxml2conftest: Check if capabilities were created successfully
Now that looking up dnsmasq is handled/mocked we can start
checking whether dnsmasq capabilities were built successfully and
error out if that wasn't the case.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Michal Privoznik [Wed, 12 Jan 2022 04:42:41 +0000 (05:42 +0100)]
networkxml2conftest: Use dnsmasqCapsNewFromBinary() to construct caps
DISCLAIMER: dnsmasq capabilities are empty as of v8.0.0-rc1~145.
In a real environment the dnsmasq capabilities are constructed
using dnsmasqCapsNewFromBinary(). We also have
dnsmasqCapsNewFromBuffer() to bypass checks that real code is
doing and just get capabilities object. The latter is used from
test suite.
However, with a little bit of mocking we can test the real life
code. All that's needed is to simulate dnsmasq's output for
--version and --help and mock a stat() that's done in
dnsmasqCapsRefreshInternal().
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Michal Privoznik [Mon, 10 Jan 2022 15:25:18 +0000 (16:25 +0100)]
virdnsmasq: Require non NULL @caps in dnsmasqCapsGetBinaryPath()
First observation: There is no way that caps->binaryPath can be
NULL. Second observation: There is no caller that passes NULL.
Let's drop the ternary operator and access @caps directly.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Michal Privoznik [Mon, 10 Jan 2022 15:19:31 +0000 (16:19 +0100)]
virdnsmasq: Lookup DNSMASQ in PATH
While it's true that our virCommand subsystem is happy with
non-absolute paths, the dnsmasq capability code is not. It stores
the path to dnsmasq within and makes it accessible via
dnsmasqCapsGetBinaryPath(). While strictly speaking no caller
necessarily needs canonicalized path, let's find dnsmasq once and
cache the result.
Therefore, when constructing the capabilities structure look up
the binary path. If DNSMASQ already contains an absolute path
then virFindFileInPath() will simply return a copy.
With this code in place, the virFileIsExecutable() check can be
removed from dnsmasqCapsRefreshInternal() because
virFindFileInPath() already made sure the binary is executable.
But introducing virFindFileInPath() means we have to mock it in
test suite because dnsmasqCaps are created in
networkxml2conftest.
Moreover, we don't need to check for dnsmasq in configure.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Michal Privoznik [Mon, 17 Jan 2022 12:22:09 +0000 (13:22 +0100)]
virdnsmasq: Don't run 'dnsmasq --help'
We don't query any capabilities of dnsmasq. We are only
interested in dnsmasq's version (obtained via 'dnsmasq
--version'). Therefore, there's no point in running 'dnsmasq
--help'. Its output is not processed even.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Michal Privoznik [Mon, 17 Jan 2022 12:20:32 +0000 (13:20 +0100)]
virdnsmasq: Drop noRefresh member from from struct _dnsmasqCaps
The noRefresh member of _dnsmasqCaps struct is set only after it
was checked for and is never checked again. This is needless and
the member can be removed. There is no way that
dnsmasqCapsRefreshInternal() can be called after
dnsmasqCapsSetFromBuffer().
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Michal Privoznik [Mon, 17 Jan 2022 12:19:26 +0000 (13:19 +0100)]
virdnsmasq: Drop mtime member from struct _dnsmasqCaps
The _dnsmasqCaps struct has @mtime member which holds the mtime
of the dnsmasq binary. The idea was that capabilities don't need
to be queried if mtime hasn't changed since the last time.
However, the code that would try to query capabilities again was
removed and now we are left with code that stores mtime but has
no use for it.
Remove the member and code that uses it.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Peter Krempa [Tue, 18 Jan 2022 09:08:03 +0000 (10:08 +0100)]
qemuDomainPinIOThread: Update live definition after process pinning
Otherwise we'll keep using the new pinning value even if it can't be
applied to the thread.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2040555 Signed-off-by: Peter Krempa <pkrempa@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com> Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Olaf Hering [Wed, 12 Jan 2022 10:45:08 +0000 (11:45 +0100)]
remove sysconfig files
sysconfig files are owned by the admin of the host. They have the
liberty to put anything they want into these files. This makes it
difficult to provide different built-in defaults.
Remove the sysconfig file and place the current desired default into
the service file.
Local customizations can now go either into /etc/sysconfig/name
or /etc/systemd/system/name.service.d/my-knobs.conf
Attempt to handle upgrades in libvirt.spec.
Dirty files which are marked as %config will be renamed to file.rpmsave.
To restore them automatically, move stale .rpmsave files away, and
catch any new rpmsave files in %posttrans.
Signed-off-by: Olaf Hering <olaf@aepfle.de> Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Michal Privoznik [Mon, 17 Jan 2022 15:46:46 +0000 (16:46 +0100)]
testutils: Terminate usage string with a new line
If a test binary is executed with an argument then usage
information is printed out (that no arguments are accepted and
what environment variables affect execution). The string is
printed onto stderr but it is not terminated with a newline
character producing not so nice output.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
examples: drop some conditionals checks from macros
We no longer need to worry about GCC version older than 7.4.0. The other
remaining conditionals checks were also overkill for the example code.
In the unlikely event that someone tries to re-use the code in a
scenario where further conditions apply they can figure out.
Reviewed-by: Ján Tomko <jtomko@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
With this list Ubuntu LTS 18.04 / openSUSE Leap 15.2 are the
constraint at 7.5.0.
When QEMU bumped GCC to 7.5.0, however, it was reported that
this is a problem for NetBSD which still ships 7.4.0.
NetBSD is not an officially targetted platform for libvirt.
Given that QEMU saw complaints about this and the feature
difference between GCC 7.4.0 and 7.5.0 is minor, I'm being
friendly and sticking 7.4.0.
Reviewed-by: Ján Tomko <jtomko@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Tim Wiederhake [Thu, 13 Jan 2022 16:01:52 +0000 (17:01 +0100)]
docs: coding-style: Rewrite section on shortening comparisons
The code style showed `bool hasFoos; if (hasFoos == true)` as a
good example in one place, only to warn against comparisons with
`true` a couple of paragraphs further down.
Merge this advice on comparing with `true` into the "Conditional
expressions" section and split the example up for readability.
Signed-off-by: Tim Wiederhake <twiederh@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com>
Michal Privoznik [Fri, 14 Jan 2022 08:51:39 +0000 (09:51 +0100)]
libxl: Allocate @libxldisk in xenParseXLDisk() on stack
In xenParseXLDisk() the @libxldisk variable (which is type of
libxl_device_disk) is allocated on heap. But this is not
necessary as nothing in the function needs that approach.
Allocate the variable on the stack and drop corresponding
VIR_FREE() call.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com>
Michal Privoznik [Fri, 14 Jan 2022 08:36:21 +0000 (09:36 +0100)]
libxl: Don't use a static buffer in xenParseXLVnuma()
The xenParseXLVnuma() function is responsible for parsing 'vnuma'
part of XL config and setting corresponding values in
virDomainDef. While doing so it uses a static buffer which is set
to data we are interested in and then parsing the buffer further
(e.g. string to integer conversion, bitmap parsing, and so on).
Well, the data we are interested in are already in a string
(@data) which can be used directly rendering this intermediary
buffer needless.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com>
Michal Privoznik [Fri, 14 Jan 2022 09:11:42 +0000 (10:11 +0100)]
virconf: Make virConfSetValue() clear consumed pointer
The way that virConfSetValue() works (and the way it is even
documented) is that the @value pointer is always consumed.
However, since the first order pointer is passed it leaves
callers in a pickle situation - they always have to set pointer
to NULL after calling virConfSetValue() to avoid touching it.
Let's switch @value to a double pointer and clear it inside the
function.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com>
Michal Privoznik [Fri, 14 Jan 2022 09:28:52 +0000 (10:28 +0100)]
src: Declare and use g_autoptr(virConfValue)
This commit declares g_autoptr() function for virConfValue type.
At the same time, it switches variable declarations to use it.
Also, in a few places we might have freed a variable twice, for
instance in xenFormatXLDomainNamespaceData(). This is because
virConfSetValue() consumes passed pointer (@value) even in case
of failure and thus any code that uses virConfSetValue() must
refrain from touching @value and it must not call
virConfFreeValue().
This semantic is not obvious and will be addressed in one of
future commits.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com>
Michal Privoznik [Fri, 14 Jan 2022 09:35:17 +0000 (10:35 +0100)]
virconf: Report an error in when virConfSetValue() fails
Callers of virConfSetValue() don't report any error, they just
pass the error blindly. Therefore, report an error when
virConfSetValue() is about to fail.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com>
storage_file: Declare virStorageSourceParseRBDColonString only in one header
The virStorageSourceParseRBDColonString() function is declared in
src/storage_file/storage_source.h and
src/storage_file/storage_source_backingstore.h but implemented
only in the .c that corresponds to the latter header file.
Therefore, drop declaration from storage_source.h as the function
is not implemented in its corresponding .c file.
Peter Krempa [Thu, 13 Jan 2022 15:59:56 +0000 (16:59 +0100)]
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>
Notable changes are:
- added flag noting that use of JSON syntax for -device was fixed
- 'dbus' backend for graphics and character devices added
- virtio-mem added 'node' property
- 'clusters' added to CPU topology
- 'open-timeout' property for NBD protocol backend
- 'wheel-left' and 'wheel-right' event types for 'input-send-event'
- increased default resolution to '1280x800' on 'virtio-gpu'
- SGX property 'section-size' changed to 'sections' incompatibly
(unused luckily)
Signed-off-by: Peter Krempa <pkrempa@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com>
Michal Privoznik [Tue, 30 Nov 2021 17:16:32 +0000 (18:16 +0100)]
tests: Report expected monitor command for simulated commands
There are two tests currently that simulate QMP talk:
qemucapabilitiestest and qemuhotplugtest. In both cases they
check whether currently executed command is the one for which
reply was provided. If not an error message is reported. However,
the error message contains only the actual command and not the
expected one. This makes it harder to navigate through .replies
files.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com>
qemu_firmware: Accept int in qemuFirmwareOSInterfaceTypeFromOsDefFirmware()
This is still rather confusing to humans reading the
code. It is clearer to just define a separate helper
method for the virDomainLoader type conversion.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The docs illustration for the <os> schema contains a mixture of
incompatible configuration options. This is rather confusing and
misleading to users. Splitting the illustration into four separate
examples clarifies the situation.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Peter Krempa [Wed, 12 Jan 2022 16:00:22 +0000 (17:00 +0100)]
virDomainSnapshotRedefinePrep: Don't do partial redefine
'virDomainSnapshotRedefinePrep' does everything needed for a redefine
when the snapshot exists but not when we are defining metadata for a new
snapshot. This gives us weird semantics.
Extract the code for replacing the definition of an existing snapshot
into a new helper 'virDomainSnapshotReplaceDef' and refactor all
callers.
Signed-off-by: Peter Krempa <pkrempa@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com>
Peter Krempa [Wed, 12 Jan 2022 15:35:01 +0000 (16:35 +0100)]
qemuSnapshotCreate: Standardize handling of the reference on @snapdef
As with qemuSnapshotRedefine, make an extra reference in a temporary
autocleaned variable and use that instead of refing the definition after
it's stolen.
Signed-off-by: Peter Krempa <pkrempa@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com>
Peter Krempa [Wed, 12 Jan 2022 14:08:25 +0000 (15:08 +0100)]
virDomainSnapshotRedefineValidate: Don't modify the snapshot definition
It is not expected that a function with 'Validate' in the name actually
modifies the validated object, even worse when it even modifies another
object and the ultimatively worst bit is that it doesn't undo the mess
if the validation fails midway.
Move the stealing of the domain definition from the definition of a
snapshot being redefined into the caller along with the call to
virDomainSnapshotAlignDisks.
Signed-off-by: Peter Krempa <pkrempa@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com>
Peter Krempa [Wed, 12 Jan 2022 13:20:04 +0000 (14:20 +0100)]
virDomainSnapshotAlignDisks: Allow alternate domain definition when redefining
Due to historical reasons we allow users to redefine an existing
snapshot without providing the domain definition which would correspond
to it. In such case we'd use the domain definition from the snapshot
that is being redefined.
To prevent callers from doing complex moving of the domain definition
object back and forth between the snapshot definitions we can add an
argument to virDomainSnapshotAlignDisks which will allow us to pass in
the alternate definition if the one from the snapshot is missing.
Signed-off-by: Peter Krempa <pkrempa@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com>
'require_match' set to true is only needed for internal snapshots taken
by hypervisors (qemu) which don't have a way to control which disks take
part in the snapshot (savevm).
To de-clutter callers we can change the argument to mean 'this code path
requires uniform snapshot for internal snapshots'.
Change the argument and fix the callers. For now all callers pass 'true'
but any new hypervisor or even usage in qemu is not going to share the
limitation.
Signed-off-by: Peter Krempa <pkrempa@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com>
Peter Krempa [Wed, 12 Jan 2022 10:02:49 +0000 (11:02 +0100)]
virDomainSnapshotRedefineValidate: Fix validation of VIR_DOMAIN_SNAPSHOT_CREATE_DISK_ONLY flag
External snapshot with memory is created without using the
VIR_DOMAIN_SNAPSHOT_CREATE_DISK_ONLY flag, but rather with properly
configuring the XML. When redefining the code should be checking the
same thing as by definition an external snapshot with memory is not a
disk-only snapshot.
Signed-off-by: Peter Krempa <pkrempa@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com>
Peter Krempa [Wed, 12 Jan 2022 09:28:23 +0000 (10:28 +0100)]
virDomainMomentAssignDef: Simplify error handling
Remove error handling from the call to 'virDomainMomentObjNew' as it
can't return NULL and replace 'virHashAddEntry' by 'g_hash_table_insert'
as we've already checked that snapshot with such name doesn't exist in
the hash table. This removes handling for two impossible errors.
Signed-off-by: Peter Krempa <pkrempa@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com>
Divya Garg [Thu, 13 Jan 2022 07:33:40 +0000 (23:33 -0800)]
Add the port allocation logic for isa-serial devices.
This commit takes care of following cases:
-> Check availability of requested ports.
->The total number of requested ports should not be more than
VIR_MAX_ISA_SERIAL_PORTS.
->The ports requested should be less than VIR_MAX_ISA_SERIAL_PORTS.
->VIR_MAX_ISA_SERIAL_PORTS should correspond to MAX_ISA_SERIAL_PORTS
specified in QEMU code commit def337ffda34d331404bd7f1a42726b71500df22.
-> Prevent duplicate device assignments to the same port.
-> In case no ports are provided in the XML, this patch scans the list of unused
isa-serial indices to automatically assign available ports for this VM.
Signed-off-by: Divya Garg <divya.garg@nutanix.com> Signed-off-by: Michal Privoznik <mprivozn@redhat.com> Reviewed-by: Michal Privoznik <mprivozn@redhat.com>