Debian's package manager will preserve mtime timestamp on binaries
from the time they are built, rather than installed. So if a
user downgrades their QEMU dpkg, the libvirt capabilities
cache will not refresh. The fix is to use ctime instead of mtime
since it cannot be faked.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Auditing all callers of virCommandRun and virCommandWait that
passed a non-NULL pointer for exit status turned up some
interesting observations. Many callers were merely passing
a pointer to avoid the overall command dying, but without
caring what the exit status was - but these callers would
be better off treating a child death by signal as an abnormal
exit. Other callers were actually acting on the status, but
not all of them remembered to filter by WIFEXITED and convert
with WEXITSTATUS; depending on the platform, this can result
in a status being reported as 256 times too big. And among
those that correctly parse the output, it gets rather verbose.
Finally, there were the callers that explicitly checked that
the status was 0, and gave their own message, but with fewer
details than what virCommand gives for free.
So the best idea is to move the complexity out of callers and
into virCommand - by default, we return the actual exit status
already cleaned through WEXITSTATUS and treat signals as a
failed command; but the few callers that care can ask for raw
status and act on it themselves.
* src/util/vircommand.h (virCommandRawStatus): New prototype.
* src/libvirt_private.syms (util/command.h): Export it.
* docs/internals/command.html.in: Document it.
* src/util/vircommand.c (virCommandRawStatus): New function.
(virCommandWait): Adjust semantics.
* tests/commandtest.c (test1): Test it.
* daemon/remote.c (remoteDispatchAuthPolkit): Adjust callers.
* src/access/viraccessdriverpolkit.c (virAccessDriverPolkitCheck):
Likewise.
* src/fdstream.c (virFDStreamCloseInt): Likewise.
* src/lxc/lxc_process.c (virLXCProcessStart): Likewise.
* src/qemu/qemu_command.c (qemuCreateInBridgePortWithHelper):
Likewise.
* src/xen/xen_driver.c (xenUnifiedXendProbe): Simplify.
* tests/reconnect.c (mymain): Likewise.
* tests/statstest.c (mymain): Likewise.
* src/bhyve/bhyve_process.c (virBhyveProcessStart)
(virBhyveProcessStop): Don't overwrite virCommand error.
* src/libvirt.c (virConnectAuthGainPolkit): Likewise.
* src/openvz/openvz_driver.c (openvzDomainGetBarrierLimit)
(openvzDomainSetBarrierLimit): Likewise.
* src/util/virebtables.c (virEbTablesOnceInit): Likewise.
* src/util/viriptables.c (virIpTablesOnceInit): Likewise.
* src/util/virnetdevveth.c (virNetDevVethCreate): Fix debug
message.
* src/qemu/qemu_capabilities.c (virQEMUCapsInitQMP): Add comment.
* src/storage/storage_backend_iscsi.c
(virStorageBackendISCSINodeUpdate): Likewise.
Signed-off-by: Eric Blake <eblake@redhat.com>
When probing QEMU capabilities fails for a binary generate a
log message with MESSAGE_ID==8ae2f3fb-2dbe-498e-8fbd-012d40afa361.
This can be directly queried from journald based on the UUID
instead of needing string grep. This lets tools like libguestfs'
bug reporting tool trivially do automated sanity tests on the
host they're running on.
$ journalctl MESSAGE_ID=8ae2f3fb-2dbe-498e-8fbd-012d40afa361
Feb 21 17:11:01 localhost.localdomain lt-libvirtd[9196]:
Failed to probe capabilities for /bin/qemu-system-alpha:
internal error: Child process (LC_ALL=C LD_LIBRARY_PATH=
/home/berrange/src/virt/libvirt/src/.libs PATH=/usr/lib64/
ccache:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:
/usr/bin:/root/bin HOME=/root USER=root LOGNAME=root
/bin/qemu-system-alpha -help) unexpected exit status 127:
/bin/qemu-system-alpha: error while loading shared libraries:
libglapi.so.0: cannot open shared object file: No such file
or directory
$ journalctl MESSAGE_ID=8ae2f3fb-2dbe-498e-8fbd-012d40afa361 --output=json
{ ...snip...
"LIBVIRT_SOURCE" : "file",
"PRIORITY" : "3",
"CODE_FILE" : "qemu/qemu_capabilities.c",
"CODE_LINE" : "2770",
"CODE_FUNC" : "virQEMUCapsLogProbeFailure",
"MESSAGE_ID" : "8ae2f3fb-2dbe-498e-8fbd-012d40afa361",
"LIBVIRT_QEMU_BINARY" : "/bin/qemu-system-xtensa",
"MESSAGE" : "Failed to probe capabilities for /bin/qemu-system-xtensa:
internal error: Child process (LC_ALL=C LD_LIBRARY_PATH=/home/berrange
/src/virt/libvirt/src/.libs PATH=/usr/lib64/ccache:/usr/local/sbin:
/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin HOME=/root
USER=root LOGNAME=root /bin/qemu-system-xtensa -help) unexpected
exit status 127: /bin/qemu-system-xtensa: error while loading shared
libraries: libglapi.so.0: cannot open shared object file: No such
file or directory\n" }
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Add a new backend for any character device. This backend uses channel
in spice connection. This channel is similar to spicevmc, but
all-purpose in contrast to spicevmc.
Apart from spicevmc, spiceport-backed chardev will not be formatted
into the command-line if there is no spice to use (with test for that
as well). For this I moved the def->graphics counting to the start
of the function so its results can be used in rest of the code even in
the future.
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
spice-server offers an API to disable file transfer messages
on the agent channel between the client and the guest.
This is supported in qemu through the disable-agent-file-xfer option.
This patch detects if QEMU supports this option, and add
a capability if does.
Signed-off-by: Francesco Romani <fromani@redhat.com>
This patch fixes a segmentation fault when creating new virtual machines using QEMU.
The segmentation fault is caused by commit f41830680e40d3ec845cefd25419bd87414b9ccf
and commit cbb6ec42e2447d7920b30d66923b2a2b2670133b.
In virQEMUCapsProbeQMPMachineTypes, when copying machines to qemuCaps, "none" is skipped.
Therefore, the value of i and "qemuCaps->nmachineTypes - 1" do not always match.
However, defIdx value (used to call virQEMUCapsSetDefaultMachine) is set using the value in i
when the array elements are in qemuCaps->nmachineTypes - 1.
So, when libvirt tries to create virtual machines using the default machine type,
qemuCaps->machineTypes[defIdx] is accessed and since the defIdx is NULL, it results in segmentation fault.
Signed-off-by: Yudai Yamagishi <yummy@sfc.wide.ad.jp>
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
AArch64 qemu has similar behavior as armv7l, like use of mmio etc.
This patch adds similar bypass checks what we have for armv7l to aarch64.
E.g. we are enabling mmio transport for Nicdev.
Making addDefaultUSB and addDefaultMemballoon to false etc.
V3:
- Adding missing domain rng schema for aarcg64 and test case in
testutilsqemu.c which was causing test suite failure
while running make check.
V2:
- Added testcase to qemuxml2argvtest as suggested
during review comments of V1.
V1:
- Initial patch.
Signed-off-by: Anup Patel <anup.patel@linaro.org>
Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org>
On a system that is enforcing FIPS, most libraries honor the
current mode by default. Qemu, on the other hand, refused to
honor FIPS mode unless you add the '-enable-fips' command
line option; worse, this option is not discoverable via QMP,
and is only present on binaries built for Linux. So, if we
detect FIPS mode, then we unconditionally ask for FIPS; either
qemu is new enough to have the option and then correctly
cripple insecure VNC passwords, or it is so old that we are
correctly avoiding a FIPS violation by preventing qemu from
starting. Meanwhile, if we don't detect FIPS mode, then
omitting the argument is safe whether the qemu has the option
(but it would do nothing because FIPS is disabled) or whether
qemu lacks the option (including in the case where we are not
running on Linux).
The testsuite was a bit interesting: we don't want our test
to depend on whether it is being run in FIPS mode, so I had
to tweak things to set the capability bit outside of our
normal interaction with capability parsing.
This fixes https://bugzilla.redhat.com/show_bug.cgi?id=1035474
* src/qemu/qemu_capabilities.h (QEMU_CAPS_ENABLE_FIPS): New bit.
* src/qemu/qemu_capabilities.c (virQEMUCapsInitQMP): Conditionally
set capability according to detection of FIPS mode.
* src/qemu/qemu_command.c (qemuBuildCommandLine): Use it.
* tests/qemucapabilitiestest.c (testQemuCaps): Conditionally set
capability to test expected output.
* tests/qemucapabilitiesdata/caps_1.2.2-1.caps: Update list.
* tests/qemucapabilitiesdata/caps_1.6.0-1.caps: Likewise.
Signed-off-by: Eric Blake <eblake@redhat.com>
The support for <boot rebootTimeout="12345"/> was added before we were
checking for qemu command line options in QMP, so we haven't properly
adapted virQEMUCaps when using it and thus we report unsupported
option with new enough qemu.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1042690
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
Map the new <panic> device in XML to the '-device pvpanic' command
line of qemu. Clients can then couple the <panic> device and the
<on_crash> directive to control behavior when the guest reports
a panic to qemu.
Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
This resolves:
https://bugzilla.redhat.com/show_bug.cgi?id=888635
(which was already closed as CANTFIX because the qemu "-boot strict"
commandline option wasn't available at the time).
Problem: you couldn't have a domain that used PXE to boot, but also
had an un-bootable disk device *even if that disk wasn't listed in the
boot order*, because if PXE timed out (e.g. due to the bridge
forwarding delay), the BIOS would move on to the next target, which
would be the unbootable disk device (again - even though it wasn't
given a boot order), and get stuck at a "BOOT DISK FAILURE, PRESS ANY
KEY" message until a user intervened.
The solution available since sometime around QEMU 1.5, is to add
"-boot strict=on" to *every* qemu command. When this is done, if any
devices have a boot order specified, then QEMU will *only* attempt to
boot from those devices that have an explicit boot order, ignoring the
rest.
The 'none' machine type is something only intended for use
by libvirt probing capabilities. It isn't something that
is useful for running real VM instances. As such it should
not be exposed to users in the capabilities.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The virQEMUCapsProbeQMPMachineTypes method iterates over machine
types copying them into the qemuCapsPtr object. It only updates
the qemuCaps->nmachinetypes value at the end though. So if OOM
occurs in the middle, the destructor of qemuCapsPtr will not
free the partially initialized machine types.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
I've noticed a SIGSEGV-ing libvirtd on the destination when the qemu
died too quickly = in Prepare phase. What is happening here is:
1) [Thread 3493] We are in qemuMigrationPrepareAny() and calling
qemuProcessStart() which subsequently calls qemuProcessWaitForMonitor()
and qemuConnectMonitor(). So far so good. The qemuMonitorOpen()
succeeds, however switching monitor to QMP mode fails as qemu died
meanwhile. That is qemuMonitorSetCapabilities() returns -1.
2013-10-08 15:54:10.629+0000: 3493: debug : qemuMonitorSetCapabilities:1356 : mon=0x14a53da0
2013-10-08 15:54:10.630+0000: 3493: debug : qemuMonitorJSONCommandWithFd:262 : Send command '{"execute":"qmp_capabilities","id":"libvirt-1"}' for write with FD -1
2013-10-08 15:54:10.630+0000: 3493: debug : virEventPollUpdateHandle:147 : EVENT_POLL_UPDATE_HANDLE: watch=17 events=13
...
2013-10-08 15:54:10.631+0000: 3493: debug : qemuMonitorSend:956 : QEMU_MONITOR_SEND_MSG: mon=0x14a53da0 msg={"execute":"qmp_capabilities","id":"libvirt-1"}
fd=-1
2013-10-08 15:54:10.631+0000: 3262: debug : virEventPollRunOnce:641 : Poll got 1 event(s)
2) [Thread 3262] The event loop is trying to do the talking to monitor.
However, qemu is dead already, remember?
2013-10-08 15:54:13.436+0000: 3262: error : qemuMonitorIORead:551 : Unable to read from monitor: Connection reset by peer
2013-10-08 15:54:13.516+0000: 3262: debug : virFileClose:90 : Closed fd 25
...
2013-10-08 15:54:13.533+0000: 3493: debug : qemuMonitorSend:968 : Send command resulted in error internal error: early end of file from monitor: possible problem:
3) [Thread 3493] qemuProcessStart() failed. No big deal. Go to the
'endjob' label and subsequently to the 'cleanup'. Since the domain is
not persistent and ret is -1, the qemuDomainRemoveInactive() is called.
This has an (unpleasant) effect of virObjectUnref()-in the @vm object.
Unpleasant because the event loop which is about to trigger EOF callback
still holds a pointer to the @vm (not the reference). See the valgrind
output below.
4) [Thread 3262] So the event loop starts triggering EOF:
2013-10-08 15:54:13.542+0000: 3262: debug : qemuMonitorIO:729 : Triggering EOF callback
2013-10-08 15:54:13.543+0000: 3262: debug : qemuProcessHandleMonitorEOF:294 : Received EOF on 0x14549110 'migt10'
And the monitor is cleaned up. This results in calling
qemuProcessHandleMonitorEOF with the @vm pointer passed. The pointer is
kept in qemuMonitor struct.
==3262== Thread 1:
==3262== Invalid read of size 4
==3262== at 0x77ECCAA: pthread_mutex_lock (in /lib64/libpthread-2.15.so)
==3262== by 0x52FAA06: virMutexLock (virthreadpthread.c:85)
==3262== by 0x52E3891: virObjectLock (virobject.c:320)
==3262== by 0x11626743: qemuProcessHandleMonitorEOF (qemu_process.c:296)
==3262== by 0x11642593: qemuMonitorIO (qemu_monitor.c:730)
==3262== by 0x52BD526: virEventPollDispatchHandles (vireventpoll.c:501)
==3262== by 0x52BDD49: virEventPollRunOnce (vireventpoll.c:648)
==3262== by 0x52BBC68: virEventRunDefaultImpl (virevent.c:274)
==3262== by 0x542D3D9: virNetServerRun (virnetserver.c:1112)
==3262== by 0x11F368: main (libvirtd.c:1513)
==3262== Address 0x14549128 is 24 bytes inside a block of size 136 free'd
==3262== at 0x4C2AF5C: free (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==3262== by 0x529B1FF: virFree (viralloc.c:580)
==3262== by 0x52E3703: virObjectUnref (virobject.c:270)
==3262== by 0x531557E: virDomainObjListRemove (domain_conf.c:2355)
==3262== by 0x1160E899: qemuDomainRemoveInactive (qemu_domain.c:2061)
==3262== by 0x1163A0C6: qemuMigrationPrepareAny (qemu_migration.c:2450)
==3262== by 0x1163A923: qemuMigrationPrepareDirect (qemu_migration.c:2626)
==3262== by 0x11682D71: qemuDomainMigratePrepare3Params (qemu_driver.c:10309)
==3262== by 0x53B0976: virDomainMigratePrepare3Params (libvirt.c:7266)
==3262== by 0x1502D3: remoteDispatchDomainMigratePrepare3Params (remote.c:4797)
==3262== by 0x12DECA: remoteDispatchDomainMigratePrepare3ParamsHelper (remote_dispatch.h:5741)
==3262== by 0x54322EB: virNetServerProgramDispatchCall (virnetserverprogram.c:435)
The mon->vm is set in qemuMonitorOpenInternal() which is the correct
place to increase @vm ref counter. The correct place to decrease the ref
counter is then qemuMonitorDispose().
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
This basically covers the talking-to-monitor part of
virQEMUCapsInitQMP. The patch itself has no real value,
but it creates an entity to be tested in the next patches.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
This resolves one of the issues in:
https://bugzilla.redhat.com/show_bug.cgi?id=1003983
This device is identical to qemu's "intel-hda" device (known as "ich6"
in libvirt), but has a different PCI device ID (which matches the ID
of the hda audio built into the ich9 chipset, of course). It's not
supported in earlier versions of qemu, so it requires a capability
bit.
Starting with qemu 1.6, the qemu-system-arm vexpress-a9 model has a
hardcoded virtio-mmio transport which enables attaching all virtio
devices.
On the command line, we have to use virtio-XXX-device rather than
virtio-XXX-pci, thankfully s390 already set the precedent here so
it's fairly straight forward.
At the XML level, this adds a new device address type virtio-mmio.
The controller and addressing don't have any subelements at the
moment because we they aren't needed for this usecase, but could
be added later if needed.
Add a test case for an ARM guest with one of every virtio device
enabled.
QEMU ARM boards don't give us any way to explicitly wire in
a -chardev, so use the old style -serial options.
Unfortunately this isn't as simple as just turning off the CHARDEV flag
for qemu-system-arm, as upcoming virtio support _will_ use device/chardev.
Add an attribute named 'removable' to the 'target' element of disks,
which controls the removable flag. For instance, on a Linux guest it
controls the value of /sys/block/$dev/removable. This option is only
valid for USB disks (i.e. bus='usb'), and its default value is 'off',
which is the same behaviour as before.
To achieve this, 'removable=on' (or 'off') is appended to the '-device
usb-storage' parameter sent to qemu when adding a USB disk via
'-disk'. A capability flag QEMU_CAPS_USB_STORAGE_REMOVABLE was added
to keep track if this option is supported by the qemu version used.
Bug: https://bugzilla.redhat.com/show_bug.cgi?id=922495
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Allow use of the usb-storage device only if the new capability flag
QEMU_CAPS_DEVICE_USB_STORAGE is set, which it is for qemu(-kvm)
versions >= 0.12.1.2-rhel62-beta.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
QEMU commit 3984890 introduced the "pci-hole64-size" property,
to i440FX-pcihost and q35-pcihost with a default setting of 2 GB.
Translate <pcihole64>x<pcihole64/> to:
-global q35-pcihost.pci-hole64-size=x for q35 machines and
-global i440FX-pcihost.pci-hole64-size=x for i440FX-based machines.
Error out on other machine types or if the size was specified
but the pcihost device lacks 'pci-hole64-size' property.
https://bugzilla.redhat.com/show_bug.cgi?id=990418
This PCI controller, named "dmi-to-pci-bridge" in the libvirt config,
and implemented with qemu's "i82801b11-bridge" device, connects to a
PCI Express slot (e.g. one of the slots provided by the pcie-root
controller, aka "pcie.0" on the qemu commandline), and provides 31
*non-hot-pluggable* PCI (*not* PCIe) slots, numbered 1-31.
Any time a machine is defined which has a pcie-root controller
(i.e. any q35-based machinetype), libvirt will automatically add a
dmi-to-pci-bridge controller if one doesn't exist, and also add a
pci-bridge controller. The reasoning here is that any useful domain
will have either an immediate (startup time) or eventual (subsequent
hot-plug) need for a standard PCI slot; since the pcie-root controller
only provides PCIe slots, we need to connect a dmi-to-pci-bridge
controller to it in order to get a non-hot-plug PCI slot that we can
then use to connect a pci-bridge - the slots provided by the
pci-bridge will be both standard PCI and hot-pluggable.
Since pci-bridge devices themselves can not be hot-plugged into a
running system (although you can hot-plug other devices into a
pci-bridge's slots), any new pci-bridge controller that is added can
(and will) be plugged into the dmi-to-pci-bridge as long as it has
empty slots available.
This patch is also changing the qemuxml2xml-pcie test from a "DO_TEST"
to a "DO_DIFFERENT_TEST". This is so that the "before" xml can omit
the automatically added dmi-to-pci-bridge and pci-bridge devices, and
the "after" xml can include it - this way we are testing if libvirt is
properly adding these devices.
https://bugzilla.redhat.com/show_bug.cgi?id=981094
The commit 0ad9025ef introduce qemu flag QEMU_CAPS_DEVICE_VIDEO_PRIMARY
for using -device VGA, -device cirrus-vga, -device vmware-svga and
-device qxl-vga. In use, for -device qxl-vga, mouse doesn't display
in guest window like the desciption in above bug.
This patch try to use -device for primary video when qemu >=1.6 which
contains the bug fix patch
Convert the type of loop iterators named 'i', 'j', k',
'ii', 'jj', 'kk', to be 'size_t' instead of 'int' or
'unsigned int', also santizing 'ii', 'jj', 'kk' to use
the normal 'i', 'j', 'k' naming
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Implement check whether (maximum) vCPUs doesn't exceed machine
type's cpu-max settings.
On older versions of QEMU the check is disabled.
Signed-off-by: Michal Novotny <minovotn@redhat.com>
When qemu >= 1.20, it is safe to use -device for primary video
device as described in 4c993d8ab.
So, we are missing the cap flag in QMP capabilities detection, this
flag can be initialized safely in virQEMUCapsInitQMPBasic.
QEMU introduced "discard" option for drive since commit a9384aff53,
<...>
@var{discard} is one of "ignore" (or "off") or "unmap" (or "on") and
controls whether @dfn{discard} (also known as @dfn{trim} or @dfn{unmap})
requests are ignored or passed to the filesystem. Some machine types
may not support discard requests.
</...>
This patch exposes the support in libvirt.
QEMU supported "discard" for "-drive" since v1.5.0-rc0:
% git tag --contains a9384aff53
contains
v1.5.0-rc0
v1.5.0-rc1
So this only detects the capability bit using virQEMUCapsProbeQMPCommandLine.
Adding a VNC WebSocket support for QEMU driver. This functionality is
in upstream qemu from commit described as v1.3.0-982-g7536ee4, so the
capability is being recognized based on QEMU version for now.
* src/qemu/qemu_capabilities.h: New capability bit.
* src/qemu/qemu_capabilities.c (virQEMUCapsProbeQMPCommandLine): New
function, based on qemuMonitorGetCommandLineOptionParameters, which was
introduced by commit bd56d0d813; use it to set new capability bit.
(virQEMUCapsInitQMP): Use new function.
Adding two cap flags for scsi-generic:
QEMU_CAPS_SCSI_GENERIC
QEMU_CAPS_SCSI_GENERIC_BOOTINDEX
Signed-off-by: Han Cheng <hanc.fnst@cn.fujitsu.com>
Signed-off-by: Osier Yang <jyang@redhat.com>
The individual hypervisor drivers were directly referencing
APIs in src/nodeinfo.c in their virDriverPtr struct. Separate
these methods, so there is always a wrapper in the hypervisor
driver. This allows the unused virConnectPtr args to be
removed from the nodeinfo.c file. Again this will ensure that
ACL checks will only be performed on invocations that are
directly associated with public API usage.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
On architectures not supporting the Intel specific programmable interval
timer, like e.g. S390, starting a domain with a clock definition containing
a pit timer results in the error "Option no-kvm-pit-reinjection not supported
for this target".
By moving the capability enablement for -no-kvm-pit-reinjection from the
InitQMPBasic section into the x86_64 and i686 only enablement section all
other architectures are no longer automatically enabled. In addition
architecture related capabilities enablements have refactored into a new
architecture bound capabilities initialization function.
Signed-off-by: Boris Fiuczynski <fiuczy@linux.vnet.ibm.com>
Signed-off-by: Viktor Mihajlovski <mihajlov@linux.vnet.ibm.com>
The source code base needs to be adapted as well. Some files
include virutil.h just for the string related functions (here,
the include is substituted to match the new file), some include
virutil.h without any need (here, the include is removed), and
some require both.
QEMU_CAPS_DEVICE_VFIO_PCI is set if the device named "vfio-pci" is
supported in the qemu binary.
QEMU_CAPS_VFIO_PCI_BOOTINDEX is set if the vfio-pci device supports
the "bootindex" parameter; for some reason, the bootindex parameter
wasn't included in early versions of vfio support (qemu 1.4) so we
have to check for it separately from vfio itself.