Bound APQNs have to be reset before tearing down the secure config via
s390_machine_unprotect(). Otherwise the Ultravisor will return a error
code.
So let's do a subsystem_reset() which includes a AP reset before the
unprotect call. We'll do a full device_reset() afterwards which will
reset some devices twice. That's ok since we can't move the
device_reset() before the unprotect as it includes a CPU clear reset
which the Ultravisor does not expect at that point in time.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Message-ID: <20230901114851.154357-1-frankja@linux.ibm.com>
Tested-by: Viktor Mihajlovski <mihajlov@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
A subsystem reset contains a reset of AP resources which has been
missing. Adding the AP bridge to the list of device types that need
reset fixes this issue.
Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com>
Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Fixes: a51b3153 ("s390x/ap: base Adjunct Processor (AP) object model")
Message-ID: <20230823142219.1046522-2-seiden@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
The check for nd->model being NULL was originally required, but in
commit e11f463295 ("s390x/virtio: use qemu_check_nic_model()")
the corresponding code had been replaced by a call to the function
qemu_check_nic_model() - and this in turn calls qemu_find_nic_model()
which contains the same check for nd->model being NULL again. So we
can remove this from the calling site now.
Message-Id: <20230804073525.11857-1-thuth@redhat.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Protected Virtualization (PV) is not a real hardware device:
it is a feature of the firmware on s390x that is exposed to
userspace via the KVM interface.
Move the pv.c/pv.h files to target/s390x/kvm/ to make this clearer.
Suggested-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230624200644.23931-1-philmd@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Mark the default NIC via the new MachineClass->default_nic setting
so that the machine-defaults code in vl.c can decide whether the
default NIC is usable or not (for example when compiling with the
"--without-default-devices" configure switch).
Message-Id: <20230512124033.502654-7-thuth@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Kernel commit 292a7d6fca33 ("KVM: s390: pv: fix asynchronous teardown
for small VMs") causes the KVM_PV_ASYNC_CLEANUP_PREPARE ioctl to fail
if the VM is not larger than 2GiB. QEMU would attempt it and fail,
print an error message, and then proceed with a normal teardown.
Avoid attempting to use asynchronous teardown altogether when the VM is
not larger than 2 GiB. This will avoid triggering the error message and
also avoid pointless overhead; normal teardown is fast enough for small
VMs.
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Fixes: c3a073c610 ("s390x/pv: Add support for asynchronous teardown for reboot")
Link: https://lore.kernel.org/all/20230421085036.52511-2-imbrenda@linux.ibm.com/
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-Id: <20230510105531.30623-2-imbrenda@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
[thuth: Fix inline function parameter in pv.h]
Signed-off-by: Thomas Huth <thuth@redhat.com>
This patch adds support for the asynchronous teardown for reboot for
protected VMs.
When attempting to tear down a protected VM, try to use the new
asynchronous interface first. If that fails, fall back to the classic
synchronous one.
The asynchronous interface involves invoking the new
KVM_PV_ASYNC_DISABLE_PREPARE command for the KVM_S390_PV_COMMAND ioctl.
This will prepare the current protected VM for asynchronous teardown.
Once the protected VM is prepared for teardown, execution can continue
immediately.
Once the protected VM has been prepared, a new thread is started to
actually perform the teardown. The new thread uses the new
KVM_PV_ASYNC_DISABLE command for the KVM_S390_PV_COMMAND ioctl. The
previously prepared protected VM is torn down in the new thread.
Once KVM_PV_ASYNC_DISABLE is invoked, it is possible to use
KVM_PV_ASYNC_DISABLE_PREPARE again. If a protected VM has already been
prepared and its cleanup has not started, it will not be possible to
prepare a new VM. In that case the classic synchronous teardown has to
be performed.
The synchronous teardown will now also clean up any prepared VMs whose
asynchronous teardown has not been initiated yet.
This considerably speeds up the reboot of a protected VM; for large VMs
especially, it could take a long time to perform a reboot with the
traditional synchronous teardown, while with this patch it is almost
immediate.
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20230214163035.44104-3-imbrenda@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Add 8.0 machine types for arm/i440fx/m68k/q35/s390x/spapr.
Reviewed-by: Cédric Le Goater <clg@kaod.org> [ppc]
Reviewed-by: Thomas Huth <thuth@redhat.com> [s390x]
Reviewed-by: Greg Kurz <groug@kaod.org> [ppc]
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20221212152145.124317-2-cohuck@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
The legacy function qdev_reset_all() performs a recursive reset,
starting from a qdev. However, it does not permit any of the devices
in the tree to use three-phase reset, because device reset goes
through the device_legacy_reset() function that only calls the single
DeviceClass::reset method.
Switch to using the device_cold_reset() function instead. This also
performs a recursive reset, where first the children are reset and
then finally the parent, but it uses the new (...in 2020...)
Resettable mechanism, which supports both the old style single-reset
method and also the new 3-phase reset handling.
This commit changes the five remaining uses of this function.
Commit created with:
sed -i -e 's/qdev_reset_all/device_cold_reset/g' hw/i386/xen/xen_platform.c hw/input/adb.c hw/remote/vfio-user-obj.c hw/s390x/s390-virtio-ccw.c hw/usb/dev-uas.c
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Fix typos (discovered with the 'codespell' utility).
Note: Though "migrateable" still seems to be a valid spelling, we change
it to "migratable" since this is the way more common spelling here.
Message-Id: <20221111182828.282251-1-thuth@redhat.com>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
zPCI enhancement features (interpretation and forward assist) were
recently introduced to improve performance on PCI passthrough devices.
To maintain the same behaviour on older Z machines, deactivate the
features with the associated properties.
Signed-off-by: Cédric Le Goater <clg@redhat.com>
Message-Id: <20221107161349.1032730-3-clg@kaod.org>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
This reverts commit 59d1ce4439.
The "zpcii-disable" machine property is redundant with the "interpret"
zPCI device property. Remove it for clarification.
Signed-off-by: Cédric Le Goater <clg@redhat.com>
Message-Id: <20221107161349.1032730-2-clg@kaod.org>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
The S390 CPU topology accepts the smp.threads argument while
in reality it does not effectively allow multthreading.
Let's keep this behavior for machines older than 7.2 and
refuse to use threads in newer machines until multithreading
is really exposed to the guest by the machine.
Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Message-Id: <20221103170150.20789-3-pmorel@linux.ibm.com>
[thuth: Small fixes to the commit description]
Signed-off-by: Thomas Huth <thuth@redhat.com>
Currently, when running 'qemu-system-s390x -M s390-ccw-virtio,help'
the s390x-specific properties are not listed anymore. This happens
because since commit d8fb7d0969 ("vl: switch -M parsing to keyval")
the properties have to be defined at the class level and not at the
instance level anymore. Fix it on s390x now, too, by moving the
registration of the properties to the class level"
Fixes: d8fb7d0969 ("vl: switch -M parsing to keyval")
Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Message-Id: <20221103170150.20789-2-pmorel@linux.ibm.com>
[thuth: Add patch description]
Signed-off-by: Thomas Huth <thuth@redhat.com>
Snapshot loading only expects to call deterministic handlers, not
non-deterministic ones. So introduce a way of registering handlers that
won't be called when reseting for snapshots.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Message-id: 20221025004327.568476-2-Jason@zx2c4.com
[PMM: updated json doc comment with Markus' text; fixed
checkpatch style nit]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Introduce an interface over which we can get information about UV data.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Steffen Eiden <seiden@linux.ibm.com>
Reviewed-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
Acked-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20221017083822.43118-8-frankja@linux.ibm.com>
The zpcii-disable machine property can be used to force-disable the use
of zPCI interpretation facilities for a VM. By default, this setting
will be off for machine 7.2 and newer.
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Message-Id: <20220902172737.170349-9-mjrosato@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
[thuth: Fix contextual conflict in ccw_machine_7_1_instance_options()]
Signed-off-by: Thomas Huth <thuth@redhat.com>
In order to fully support MSA_EXT_5, we have to support the SHA-512
special instructions. So implement those.
The implementation began as something TweetNacl-like, and then was
adjusted to be useful here. It's not very beautiful, but it is quite
short and compact, which is what we're going for.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
[ restructure, add missing exception, add comments, fixup CPU model ]
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20220922153820.221811-1-david@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Add stfle 197 (processor-activity-instrumentation extension 1) to the
gen16 default model and fence it off for 7.1 and older.
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20220727135120.12784-1-borntraeger@linux.ibm.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
The machine name already contains the words "ccw" and "virtio", so
using "VirtIO-ccw" in the description likely does not really help
the average user to get an idea what this machine type is about.
Thus let's switch to "Virtual s390x machine" now, since "virtual
machine" should be a familiar term, and "s390x" signals that this
is about 64-bit guests (unlike S390 which could mean that it is
31-bit only).
Also expand "v" to "version", since this makes it easier to use
this macro also with non-numeric machine names in downstream.
Message-Id: <20220506065026.513590-1-thuth@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
[ dh: take care of compat machines ]
Signed-off-by: David Miller <dmiller423@gmail.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20220428094708.84835-13-david@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
TCG implements everything we need to run basic z15 OS+software
Signed-off-by: David Miller <dmiller423@gmail.com>
Message-Id: <20220223223117.66660-3-dmiller423@gmail.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Add 7.0 machine types for arm/i440fx/q35/s390x/spapr.
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20211217143948.289995-1-cohuck@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Now we have a common structure SMPCompatProps used to store information
about SMP compatibility stuff, so we can also move smp_prefer_sockets
there for cleaner code.
No functional change intended.
Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210929025816.21076-15-wangyanan55@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In the real SMP hardware topology world, it's much more likely that
we have high cores-per-socket counts and few sockets totally. While
the current preference of sockets over cores in smp parsing results
in a virtual cpu topology with low cores-per-sockets counts and a
large number of sockets, which is just contrary to the real world.
Given that it is better to make the virtual cpu topology be more
reflective of the real world and also for the sake of compatibility,
we start to prefer cores over sockets over threads in smp parsing
since machine type 6.2 for different arches.
In this patch, a boolean "smp_prefer_sockets" is added, and we only
enable the old preference on older machines and enable the new one
since type 6.2 for all arches by using the machine compat mechanism.
Suggested-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta@ionos.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210929025816.21076-10-wangyanan55@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add the new gen16 features to the default model and fence them for
machine version 6.1 and earlier.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210907101017.27126-1-borntraeger@de.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Add 6.2 machine types for arm/i440fx/q35/s390x/spapr.
Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta@ionos.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
TCG implements everything we need to run basic z14 OS+software.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210608092337.12221-27-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Stop including exec/address-spaces.h in files that don't need it.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210416171314.2074665-5-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Stop including cpu.h in files that don't need it.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210416171314.2074665-4-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Stop including hw/boards.h in files that don't need it.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210416171314.2074665-3-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
At least some s390 cpu models support "Protected Virtualization" (PV),
a mechanism to protect guests from eavesdropping by a compromised
hypervisor.
This is similar in function to other mechanisms like AMD's SEV and
POWER's PEF, which are controlled by the "confidential-guest-support"
machine option. s390 is a slightly special case, because we already
supported PV, simply by using a CPU model with the required feature
(S390_FEAT_UNPACK).
To integrate this with the option used by other platforms, we
implement the following compromise:
- When the confidential-guest-support option is set, s390 will
recognize it, verify that the CPU can support PV (failing if not)
and set virtio default options necessary for encrypted or protected
guests, as on other platforms. i.e. if confidential-guest-support
is set, we will either create a guest capable of entering PV mode,
or fail outright.
- If confidential-guest-support is not set, guests might still be
able to enter PV mode, if the CPU has the right model. This may be
a little surprising, but shouldn't actually be harmful.
To start a guest supporting Protected Virtualization using the new
option use the command line arguments:
-object s390-pv-guest,id=pv0 -machine confidential-guest-support=pv0
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20201026143028.3034018-13-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add 6.0 machine types for arm/i440fx/q35/s390x/spapr.
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20201109173928.1001764-1-cohuck@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The Control Program Name Code (CPNC) portion of the diag318
info must be set within the SIE block of each VCPU in the
configuration. The handler will iterate through each VCPU
and dirty the diag318_info reg to be synced with KVM on a
subsequent sync_regs call.
Additionally, the diag318 info resets must be handled via
userspace. As such, QEMU will reset this value for each
VCPU during a modified clear, load normal, and load clear
reset event.
Fixes: fabdada935 ("s390: guest support for diagnose 0x318")
Signed-off-by: Collin Walling <walling@linux.ibm.com>
Message-Id: <20201113221022.257054-1-walling@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Janosch Frank <frankja@de.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Seems a more appropriate location for them.
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Currently, a subsystem reset event leaves PCI devices enabled, causing
issues post-reset in the guest (an example would be after a kexec). These
devices need to be reset during a subsystem reset, allowing them to be
properly re-enabled afterwards. Add the S390 PCI host bridge to the list
of qdevs to be reset during subsystem reset.
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Acked-by: Halil Pasic <pasic@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: qemu-stable@nongnu.org
Message-Id: <1602767767-32713-1-git-send-email-mjrosato@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
These were deprecated since 4.0, remove both HMP and QMP variants.
Users should use device_add command instead. To get list of
possible CPUs and options, use 'info hotpluggable-cpus' HMP
or query-hotpluggable-cpus QMP command.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20200915120403.1074579-1-imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Rename it to be consistent with S390_CCW_MACHINE and
TYPE_S390_CCW_MACHINE.
This will make future conversion to OBJECT_DECLARE* easier.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Tested-By: Roman Bolshakov <r.bolshakov@yadro.com>
Message-Id: <20200825192110.3528606-49-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Add 5.2 machine types for arm/i440fx/q35/s390x/spapr.
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20200819144016.281156-1-cohuck@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
As pointed out by Peter, g_memdup(ms->loadparm, sizeof(ms->loadparm) + 1)
reads one past of the end of ms->loadparm, so g_memdup() can not be used
here.
Let's use g_strndup instead!
Fixes: d664548328 ("s390x/s390-virtio-ccw: fix loadparm property getter")
Fixes: Coverity CID 1431058
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20200730130156.35063-1-pasic@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
The function machine_get_loadparm() is supposed to produce a C-string,
that is a NUL-terminated one, but it does not. ElectricFence can detect
this problem if the loadparm machine property is used.
Let us make the returned string a NUL-terminated one.
Fixes: 7104bae9de ("hw/s390x: provide loadparm property for the machine")
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20200723162717.88485-1-pasic@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>