This patch implements support for the "cpu-add" QMP command that plugs
CPUs into a live guest. The "cpu-add" command was introduced in QEMU
1.5. For the hotplug to work machine type "pc-i440fx-1.5" is required.
The qemu guest agent allows to online and offline CPUs from the
perspective of the guest. This patch adds helpers that call
'guest-get-vcpus' and 'guest-set-vcpus' guest agent functions and
convert the data for internal libvirt usage.
https://bugzilla.redhat.com/show_bug.cgi?id=964177
Though both libvirt and QEMU's document say RTC_CHANGE returns
the offset from the host UTC, qemu actually returns the offset
from the specified date instead when specific date is provided
(-rtc base=$date).
It's not safe for qemu to fix it in code, it worked like that
for 3 years, changing it now may break other QEMU use cases.
What qemu tries to do is to fix the document:
http://lists.gnu.org/archive/html/qemu-devel/2013-05/msg04782.html
And in libvirt side, instead of replying on the value from qemu,
this converts the offset returned from qemu to the offset from
host UTC, by:
/*
* a: the offset from qemu RTC_CHANGE event
* b: The specified date (-rtc base=$date)
* c: the host date when libvirt gets the RTC_CHANGE event
* offset: What libvirt will report
*/
offset = a + (b - c);
The specified date (-rtc base=$date) is recorded in clock's def as
an internal only member (may be useful to exposed outside?).
Internal only XML tag "basetime" is introduced to not lose the
guest's basetime after libvirt restarting/reloading:
<clock offset='variable' adjustment='304' basis='utc' basetime='1370423588'/>
Currently, a listen address for a SPICE server can be specified. Later,
when the domain is migrated, we need to relocate the graphics which
involves telling new destination to the SPICE server. However, we can't
just assume the listen address is the new location, because the listen
address can be ANYCAST (0.0.0.0 for IPv4, :: for IPv6). In which case,
we want to pass the remote hostname. But there are some troubles with
ANYCAST. In both IPv4 and IPv6 it has many ways for specifying such
address. For instance, in IPv4: 0, 0.0, 0.0.0, 0.0.0.0. The number of
variations gets bigger in IPv6 world. Hence, in order to check for
ANYCAST address sanely, we should take the provided listen address,
parse it and format back in it's full form. Which is exactly what this
patch does.
The work was done at the time of snapshot xmlstring parsing
if (offline && def->memory &&
def->memory != VIR_DOMAIN_SNAPSHOT_LOCATION_NONE) {
virReportError(...);
}
This should resolve:
https://bugzilla.redhat.com/show_bug.cgi?id=959191
The problem was that qemuUpdateActivePciHostdevs was returning 0
(success) when no hostdevs were present, but would otherwise return -1
(failure) even when it completed successfully. It is only called from
qemuProcessReconnect(), and when qemuProcessReconnect got back an
error, it would not only stop reconnecting, but would terminate the
guest qemu process "to remove danger of it ending up running twice if
user tries to start it again later".
(This bug was introduced in commit 011cf7ad, which was pushed between
v1.0.2 and v1.0.3, so all maintenance branches from v1.0.3 up to 1.0.5
will need this one line patch applied.)
A literal IPv6 must be escaped, otherwise migration fails with:
unable to execute QEMU command 'drive-mirror': address resolution failed
for f0::0d:5901: Servname not supported for ai_socktype
since QEMU treats everything after the first ':' as the port.
If snapshot creation failed for example due to invalid use of the
"REUSE_EXTERNAL" flag, libvirt killed access to the original image file
instead of the new image file. On machines with selinux this kills the
whole VM as the selinux context is enforced immediately.
* qemu_driver.c:qemuDomainSnapshotUndoSingleDiskActive():
- Kill access to the new image file instead of the old one.
Partially resolves: https://bugzilla.redhat.com/show_bug.cgi?id=906639
A bug in Cygwin [1] and poor error messages from gcc [2] lead
to this confusing compilation error:
qemu/qemu_monitor.c:418:9: error: passing argument 2 of 'sendmsg' from incmpatible pointer type
/usr/include/sys/socket.h:42:11: note: expected 'const struct msghdr *' but argument is of type 'struct msghdr *'
[1] http://cygwin.com/ml/cygwin/2013-05/msg00451.html
[2] http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57475
* src/qemu/qemu_monitor.c (includes): Include <sys/socket.h>
before <sys/un.h>.
Signed-off-by: Eric Blake <eblake@redhat.com>
This is a recurring problem for cygwin :)
For example, see commit 23a4df88.
qemu/qemu_driver.c: In function 'qemuStateInitialize':
qemu/qemu_driver.c:691:13: error: format '%d' expects type 'int', but argument 8 has type 'uid_t' [-Wformat]
* src/qemu/qemu_driver.c (qemuStateInitialize): Add casts.
* daemon/remote.c (remoteDispatchAuthList): Likewise.
Signed-off-by: Eric Blake <eblake@redhat.com>
A cygwin build of the qemu driver fails with:
qemu/qemu_process.c: In function 'qemuPrepareCpumap':
qemu/qemu_process.c:1803:31: error: 'CPU_SETSIZE' undeclared (first use in this function)
CPU_SETSIZE is a Linux extension in <sched.h>; a bit more portable
is using sysconf if _SC_NPROCESSORS_CONF is defined (several platforms
have it, including Cygwin). Ultimately, I would have preferred to
use gnulib's 'nproc' module, but it is currently under an incompatible
license.
* src/qemu/qemu_conf.h (QEMUD_CPUMASK_LEN): Provide definition on
cygwin.
Signed-off-by: Eric Blake <eblake@redhat.com>
Currently, if there's an error opening /dev/vhost-net (e.g. because
it doesn't exist) but it's not required we proceed with vhostfd array
filled with -1 and vhostfdSize unchanged. Later, when constructing
the qemu command line only non-negative items within vhostfd array
are taken into account. This means, vhostfdSize may be greater than
the actual count of non-negative items in vhostfd array. This results
in improper command line arguments being generated, e.g.:
-netdev tap,fd=21,id=hostnet0,vhost=on,vhostfd=(null)
If we are just ejecting media, ret == -1 even after the retry loop
determines that the tray is open, as requested. This means media
disconnect always report's error.
Fix it, and fix some other mini issues:
- Don't overwrite the 'eject' error message if the retry loop fails
- Move the retries decrement inside the loop, otherwise the final loop
might succeed, yet retries == 0 and we will raise error
- Setting ret = -1 in the disk->src check is unneeded
- Fix comment typos
cc: mprivozn@redhat.com
Currently qemuDomainReboot() does reboot in two phases:
qemuMonitorSystemPowerdown() and qemuProcessFakeReboot().
qemuMonitorSystemPowerdown() shutdowns the domain and saves domain
state/reason as VIR_DOMAIN_SHUTDOWN_UNKNOWN.
qemuProcessFakeReboot() sets domain state/reason to
VIR_DOMAIN_RESUMED_UNPAUSED but does not save domain state changes.
Subsequent restart of libvirtd leads to restoring domain state/reason to
saved that is VIR_DOMAIN_SHUTDOWN_UNKNOWN and to automatic shutdown of
the domain. This commit adds virDomainSaveStatus() into
qemuProcessFakeReboot() to avoid unexpected shutdowns.
With previous patch, we accept negative value as length of string to
duplicate. So there is no need to pass strlen(src) in case we want to do
duplicate the whole string.
Function qemuDomainSetBlockIoTune() was checking QEMU capabilities
even when !(flags & VIR_DOMAIN_AFFECT_LIVE) and the domain was
shutoff, resulting in the following problem:
virsh # domstate asdf; blkdeviotune asdf vda --write-bytes-sec 100
shut off
error: Unable to change block I/O throttle
error: unsupported configuration: block I/O throttling not supported with this QEMU binary
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=965016
Since f03dcc5 we use [::] as the listening address both on qemu
command line in -incoming and in nbd-server-start QMP command.
However the latter requires just :: without the braces.
In order to learn libvirt multiqueue several things must be done:
1) The '/dev/net/tun' device needs to be opened multiple times with
IFF_MULTI_QUEUE flag passed to ioctl(fd, TUNSETIFF, &ifr);
2) Similarly, '/dev/vhost-net' must be opened as many times as in 1)
in order to keep 1:1 ratio recommended by qemu and kernel folks.
3) The command line construction code needs to switch from 'fd=X' to
'fds=X:Y:...:Z' and from 'vhostfd=X' to 'vhostfds=X:Y:...:Z'.
4) The monitor handling code needs to learn to pass multiple FDs.
In 84c59ffa I've tried to fix changing ejectable media process. The
process should go like this:
1) we need to call 'eject' on the monitor
2) we should wait for 'DEVICE_TRAY_MOVED' event
3) now we can issue 'change' command
However, while waiting in step 2) the domain monitor was locked. So
even if qemu reported the desired event, the proper callback was not
called immediately. The monitor handling code needs to lock the
monitor in order to read the event. So that's the first lock we must
not hold while waiting. The second one is the domain lock. When
monitor handling code reads an event, the appropriate callback is
called then. The first thing that each callback does is locking the
corresponding domain as a domain or its device is about to change
state. So we need to unlock both monitor and VM lock. Well, holding
any lock while sleep()-ing is not the best thing to do anyway.
Since 0d70656afd, it starts to access the sysfs files to build
the qemu command line (by virSCSIDeviceGetSgName, which is to find
out the scsi generic device name by adpater🚌target:unit), there
is no way to work around, qemu wants to see the scsi generic device
like "/dev/sg6" anyway.
And there might be other places which need to access sysfs files
when building qemu command line in future.
Instead of increasing the arguments of qemuBuildCommandLine, this
introduces a new callback for qemuBuildCommandLine, and thus tests
can register their own callbacks for sysfs test input files accessing.
* src/qemu/qemu_command.h: (New callback struct
qemuBuildCommandLineCallbacks;
extern buildCommandLineCallbacks)
* src/qemu/qemu_command.c: (wire up the callback struct)
* src/qemu/qemu_driver.c: (Use the new syntax of qemuBuildCommandLine)
* src/qemu/qemu_hotplug.c: Likewise
* src/qemu/qemu_process.c: Likewise
* tests/testutilsqemu.[ch]: (Helper testSCSIDeviceGetSgName;
callback struct testCallbacks;)
* tests/qemuxml2argvtest.c: (Use testCallbacks)
* src/tests/qemuxmlnstest.c: (Like above)
Resolves:https://bugzilla.redhat.com/show_bug.cgi?id=927620
#kill -STOP `pidof qemu-kvm`
#virsh destroy $guest --graceful
error: Failed to destroy domain testVM
error: An error occurred, but the cause is unknown
With --graceful, SIGTERM always is emitted to kill driver
process, but it won't success till burning out waiting time
in case of process being stopped.
But domain destroy without --graceful can work, SIGKILL will
be emitted to the stopped process after 10 secs which always
kills a process even one that is currently stopped.
So report an error after burning out waiting time in this case.
Change bbe97ae968 caused the
QEMU driver to ignore ENOENT errors from cgroups, in order
to cope with missing /proc/cgroups. This is not good though
because many other things can cause ENOENT and should not
be ignored. The callers expect to see ENXIO when cgroups
are not present, so adjust the code to report that errno
when /proc/cgroups is missing
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
