In case libvirtd is asked to unplug a device but the device is actually
unplugged later when libvirtd is not running, we need to detect that and
remove such device when libvirtd starts again and reconnects to running
domains.

In all qemu APIs we tend to prefer qemuDomObjFromDomain over
virDomainObjListFindByUUID. But somehow the
qemuDomainGetSchedulerType left unattended.

Implement the new API that will handle setting the balloon driver statistics
collection period in order to enable or disable the collection dynamically.

If users haven't configured guest agent then qemuAgentCommand() will
dereference a NULL 'mon' pointer, which causes crash of libvirtd when
using agent based cpu (un)plug.

With the patch, when the qemu-ga service isn't running in the guest,
a expected error "error: Guest agent is not responding: Guest agent
not available for now" will be raised, and the error "error: argument
unsupported: QEMU guest agent is not configured" is raised when the
guest hasn't configured guest agent.

GDB backtrace:

 (gdb) bt
 #0  virNetServerFatalSignal (sig=11, siginfo=<value optimized out>, context=<value optimized out>) at rpc/virnetserver.c:326
 #1  <signal handler called>
 #2  qemuAgentCommand (mon=0x0, cmd=0x7f39300017b0, reply=0x7f394b090910, seconds=-2) at qemu/qemu_agent.c:975
 #3  0x00007f39429507f6 in qemuAgentGetVCPUs (mon=0x0, info=0x7f394b0909b8) at qemu/qemu_agent.c:1475
 #4  0x00007f39429d9857 in qemuDomainGetVcpusFlags (dom=<value optimized out>, flags=9) at qemu/qemu_driver.c:4849
 #5  0x00007f3957dffd8d in virDomainGetVcpusFlags (domain=0x7f39300009c0, flags=8) at libvirt.c:9843

How to reproduce?

 # To start a guest without guest agent configuration
 # then run the following cmdline

 # virsh vcpucount foobar --guest
 error: End of file while reading data: Input/output error
 error: One or more references were leaked after disconnect from the hypervisor
 error: Failed to reconnect to the hypervisor

RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=984821Signed-off-by: NAlex Jia <ajia@redhat.com>
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

Since previous patches has prepared everything for us, we may now
implement live hotplug of a character device.

There are two levels on which a device may be hotplugged: config
and live. The config level requires just an insert or remove from
internal domain definition structure, which is exactly what this
patch does. There is currently no implementation for a chardev
update action, as there's not much to be updated. But more
importantly, the only thing that can be updated is path or socket
address by which chardevs are distinguished. So the update action
is currently not supported.

With current code, error reporting for unsupported devices for hot plug,
unplug and update is total mess. The VIR_ERR_CONFIG_UNSUPPORTED error
code is reported instead of VIR_ERR_OPERATION_UNSUPPORTED. Moreover, the
error messages are not helping to find the root cause (lack of
implementation).

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: NDaniel P. Berrange <berrange@redhat.com>

CVE-2013-2230

Don't overwrite the callback ID returned by
virDomainEventStateRegisterID in ret by 0.

Introduced by abf75aea.

Introduced in commit d47eff88.

* src/qemu/qemu_driver.c (qemuDomainSetVcpusFlags): Fix spelling.
Signed-off-by: NEric Blake <eblake@redhat.com>

Caused by 76397360.

Ensure that all APIs which list domain objects filter
them against the access control system.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Add doDumpCoreToAutoPath to implement
'coredump-destroy' and 'coredump-restart' events of the 'on_crash'
in the XML when domain crashed.

Add monitor callback API domainGuestPanic, that implements
'destroy', 'restart' and 'preserve' events of the 'on_crash'
in the XML when domain crashed.

Split the code to make the driver workpool more generalized

After abf75aea the compiler screams:

qemu/qemu_driver.c: In function 'qemuNodeDeviceDetachFlags':
qemu/qemu_driver.c:10693:9: error: 'domain' may be used uninitialized in this function [-Werror=maybe-uninitialized]
     pci = virPCIDeviceNew(domain, bus, slot, function);
         ^
qemu/qemu_driver.c:10693:9: error: 'bus' may be used uninitialized in this function [-Werror=maybe-uninitialized]
qemu/qemu_driver.c:10693:9: error: 'slot' may be used uninitialized in this function [-Werror=maybe-uninitialized]
qemu/qemu_driver.c:10693:9: error: 'function' may be used uninitialized in this function [-Werror=maybe-uninitialized]

Since the other functions qemuNodeDeviceReAttach and qemuNodeDeviceReset
looks exactly the same, I've initialized the variables there as well.
However, I am still wondering why those functions don't matter to gcc
while the first one does.

Mention the domain name that is being saved and remove the unneeded
variable that only stores a constant.

If qemuMonitorBlockJob returned 0, qemuDomainBlockPivot
might return 0 even if an error occured.

https://bugzilla.redhat.com/show_bug.cgi?id=977678

The driver arg to virPCIDeviceDetach is no longer used (the name of the stub driver is now set in the virPCIDevice object, and virPCIDeviceDetach retrieves it from there). Remove it.

virPCIDeviceDetach would previously sometimes consume the input device
object (to put it on the inactive list) and sometimes not. Avoiding
memory leaks required checking beforehand to see if the device was
already on the list, and freeing the device object in the caller only
if there wasn't already an identical object on the inactive list.

This patch makes it consistent - virPCIDeviceDetach will *never*
consume the input virPCIDevice object; if it needs to put one on the
inactive list, it will create a copy and put *that* on the list. This
way the caller knows that it is always their responsibility to free
the device object they created.

Previously stubDriver was always set from a string literal, so it was
okay to use a const char * that wasn't freed when the virPCIDevice was
freed. This will not be the case in the near future, so it is now a
char* that is allocated in virPCIDeviceSetStubDriver() and freed
during virPCIDeviceFree().

Insert calls to the ACL checking APIs in all QEMU driver
entrypoints.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

We can only pass values up to LLONG_MAX through JSON
and QEMU checks if the int64_t number is not negative
at startup since 1.5.0.

https://bugzilla.redhat.com/show_bug.cgi?id=974010

As a consequence of the cgroup layout changes from commit '632f78ca', the
qemuDomainGetSchedulerParameters[Flags]()' and qemuGetSchedulerType() APIs
failed to return data for a non running domain.  This can be seen through
a 'virsh schedinfo <domain>' command which returns:

Scheduler      : Unknown
error: Requested operation is not valid: cgroup CPU controller is not mounted

Prior to that change a non running domain would return:

Scheduler      : posix
cpu_shares     : 0
vcpu_period    : 0
vcpu_quota     : 0
emulator_period: 0
emulator_quota : 0

This patch will restore the capability to return configuration only data
for a non running domain regardless of whether cgroups are available.

Paolo Bonzini pointed out that it's actually possible to migrate a qemu
instance that was paused due to I/O error and it will be able to work on
the destination if the storage is accessible.

This patch introduces flag VIR_MIGRATE_ABORT_ON_ERROR that cancels the
migration in case an I/O error happens while it's being performed and
allows migration without this flag. This flag can be possibly used for
other error reasons that may be introduced in the future.

Convert input XML to migratable before using it in
qemuDomainSaveImageOpen.

XML in the save image is migratable, i.e. doesn't contain implicit
controllers. If these controllers were in a non-default order in the
input XML, the ABI check would fail. Removing and re-adding these
controllers fixes it.

https://bugzilla.redhat.com/show_bug.cgi?id=834196

Avoid leaking virDomainDef if Prepare phase fails before it gets to
qemuMigrationPrepareAny.

This patch fixes changes done in commit 29c1e913
that was pushed without implementing review feedback.

The flag introduced by the patch is changed to VIR_DOMAIN_VCPU_GUEST and
documentation makes the difference between regular hotplug and this new
functionality more explicit.

The virsh options that enable the use of the new flag are changed to
"--guest" and the documentation is fixed too.

Currently, there's a path to use the ncpuinfo variable uninitialized,
which leads to a compiler warning:

    qemu/qemu_driver.c: In function 'qemuDomainGetVcpusFlags':
    qemu/qemu_driver.c:4573:9: error: 'ncpuinfo' may be used
    uninitialized in this function [-Werror=maybe-uninitialized]
             for (i = 0; i < ncpuinfo; i++) {
             ^

This patch adds support for agent-based cpu disabling and enabling to
qemuDomainSetVcpusFlags() API.

This patch implements the VIR_DOMAIN_VCPU_AGENT flag for the
qemuDomainGetVcpusFlags() libvirt API implementation.