virDomainSaveConfig calls virDomainDefFormat which was setting the caps
to NULL, thus keeping the old behaviour (i.e. not looking at
netprefix). This patch adds the virCapsPtr to the function and allows
the configuration to be saved and skipping interface names that were
registered with virCapabilitiesSetNetPrefix().
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
This patch creates two bitmaps, one for macvlan device names and one
for macvtap. The bitmap position is used to indicate that libvirt is
currently using a device with the name macvtap%d/macvlan%d, where %d
is the position in the bitmap. When requested to create a new
macvtap/macvlan device, libvirt will now look for the first clear bit
in the appropriate bitmap and derive the device name from that rather
than just starting at 0 and counting up until one works.
When libvirtd is restarted, the qemu driver code that reattaches to
active domains calls the appropriate function to "re-reserve" the
device names as it is scanning the status of running domains.
Note that it may seem strange that the retry counter now starts at
8191 instead of 5. This is because we now don't do a "pre-check" for
the existence of a device once we've reserved it in the bitmap - we
move straight to creating it; although very unlikely, it's possible
that someone has a running system where they have a large number of
network devices *created outside libvirt* named "macvtap%d" or
"macvlan%d" - such a setup would still allow creating more devices
with the old code, while a low retry max in the new code would cause a
failure. Since the objective of the retry max is just to prevent an
infinite loop, and it's highly unlikely to do more than 1 iteration
anyway, having a high max is a reasonable concession in order to
prevent lots of new failures.
So I can observe this crasher that with freshly started daemon
(and virtlogd enabled) I am trying to startup a domain that
immediately dies (because it's said to use huge pages but I
haven't allocated a single one in the pool). Hardly reproducible
with -O0 or under valgrind. But I just got lucky:
==20469== Invalid write of size 8
==20469== at 0x4C2E99B: memcpy@GLIBC_2.2.5 (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==20469== by 0x217EDD07: qemuProcessReadLog (qemu_process.c:1670)
==20469== by 0x217EDE1D: qemuProcessReportLogError (qemu_process.c:1696)
==20469== by 0x217EE8C1: qemuProcessWaitForMonitor (qemu_process.c:1957)
==20469== by 0x217F6636: qemuProcessLaunch (qemu_process.c:4955)
==20469== by 0x217F71A4: qemuProcessStart (qemu_process.c:5152)
==20469== by 0x21846582: qemuDomainObjStart (qemu_driver.c:7396)
==20469== by 0x218467DE: qemuDomainCreateWithFlags (qemu_driver.c:7450)
==20469== by 0x21846845: qemuDomainCreate (qemu_driver.c:7468)
==20469== by 0x5611CD0: virDomainCreate (libvirt-domain.c:6753)
==20469== by 0x125D9A: remoteDispatchDomainCreate (remote_dispatch.h:3613)
==20469== by 0x125CB7: remoteDispatchDomainCreateHelper (remote_dispatch.h:3589)
==20469== Address 0x27a52ad0 is 0 bytes after a block of size 5,584 alloc'd
==20469== at 0x4C29F80: malloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==20469== by 0x9B8D1DB: xdr_string (in /lib64/libc-2.21.so)
==20469== by 0x563B39C: xdr_virLogManagerProtocolNonNullString (log_protocol.c:24)
==20469== by 0x563B6B7: xdr_virLogManagerProtocolDomainReadLogFileRet (log_protocol.c:123)
==20469== by 0x164B34: virNetMessageDecodePayload (virnetmessage.c:407)
==20469== by 0x5682360: virNetClientProgramCall (virnetclientprogram.c:379)
==20469== by 0x563B30E: virLogManagerDomainReadLogFile (log_manager.c:272)
==20469== by 0x217CD613: qemuDomainLogContextRead (qemu_domain.c:2485)
==20469== by 0x217EDC76: qemuProcessReadLog (qemu_process.c:1660)
==20469== by 0x217EDE1D: qemuProcessReportLogError (qemu_process.c:1696)
==20469== by 0x217EE8C1: qemuProcessWaitForMonitor (qemu_process.c:1957)
==20469== by 0x217F6636: qemuProcessLaunch (qemu_process.c:4955)
This points to memmove() in qemuProcessReadLog(). Imagine we just
read the following string from qemu:
"abc\n2016-01-18T09:40:44.022744Z qemu-system-x86_64: Error\n"
After the first pass of the while() loop in the
qemuProcessReadLog() (in which we have taken the false branch in
the if) @buf still points to the beginning of the string,
@filter_next points to the beginning of the second line. So we
start second iteration because there is yet another newline
character at the end. In this iteration @eol points to it
actually. Now, the control gets inside true branch of if(). Just
to remind you:
got = 58
filter_next = buf + 5,
eol = buf + 58.
Therefore skip = 54 which is correct. The message we want to skip
is 54 bytes long. However:
memmove(filter_next, eol + 1, (got - skip) +1);
which is
memmove(filter_next, eol + 1, 5)
is obviously wrong as there is only one byte we can access, not 5!
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
This reverts commit a41c00b472.
After much testing and upstream discussion this has been deemed to be
the incorrect operation since it means we no longer have any guarantee
about which resource controllers the QEMU processes in general are in.
So, you try to start a domain, but before we even get to the part
where chardev part of qemu command line is generated (and
possibly missing path to unix sockets is made up) an error occurs
which results in calling qemuProcessStop. This will then try to
clean up the mess and possibly ends up calling unlink(NULL).
==8085== Thread 3:
==8085== Syscall param unlink(pathname) points to unaddressable byte(s)
==8085== at 0xA85EA57: unlink (in /lib64/libc-2.21.so)
==8085== by 0x213D3C24: qemuProcessCleanupChardevDevice (qemu_process.c:2866)
==8085== by 0x558D6B1: virDomainChrDefForeach (domain_conf.c:22924)
==8085== by 0x213DA9AE: qemuProcessStop (qemu_process.c:5326)
==8085== by 0x213DA2F2: qemuProcessStart (qemu_process.c:5190)
==8085== by 0x2142957F: qemuDomainObjStart (qemu_driver.c:7396)
==8085== by 0x214297DB: qemuDomainCreateWithFlags (qemu_driver.c:7450)
==8085== by 0x21429842: qemuDomainCreate (qemu_driver.c:7468)
==8085== by 0x5611B95: virDomainCreate (libvirt-domain.c:6753)
==8085== by 0x125D9A: remoteDispatchDomainCreate (remote_dispatch.h:3613)
==8085== by 0x125CB7: remoteDispatchDomainCreateHelper (remote_dispatch.h:3589)
==8085== by 0x568BF41: virNetServerProgramDispatchCall (virnetserverprogram.c:437)
==8085== Address 0x0 is not stack'd, malloc'd or (recently) free'd
==8085==
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
While this is no functional change, whole channel definition is
going to be needed very soon. Moreover, while touching this obey
const correctness rule in qemuAgentOpen() - so far it was passed
regular pointer to channel config even though the function is
expected to not change pointee at all. Pass const pointer
instead.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
The structure actually contains migration statistics rather than just
the status as the name suggests. Renaming it as
qemuMonitorMigrationStats removes the confusion.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
My commit 674afcb09e moved computing the
default listen address from qemuMigrationPrepareAny to
qemuMigrationPrepareIncoming. However, I didn't notice listenAddress was
later passed to qemuMigrationStartNBDServer. Thus, it would be called
with the original value of listenAddress (NULL).
Let's add the updated listen address to qemuProcessIncomingDef and use
it when starting NBD servers.
Reported-by: Michael Chapman <mike@very.puzzling.org>
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
In commit 686eb7a24f, the break was not considered part of the
condition, hence breaking after first node when searching.
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
The machine cgroup is a superset, a parent to the emulator and vcpuX
cgroups. The parent cgroup should never have any tasks directly in it.
In fact the parent cpuset might contain way more cpus than the sum of
emulatorpin and vcpupins. So putting tasks in the superset will allow
them to run outside of <cputune>.
Signed-off-by: Henning Schild <henning.schild@siemens.com>
When user configures vhost-user interface and forgets to also configure
any shared memory, the search for the root cause of non-operational
interface might take unpleasantly long time. Let's enhance user
experience by emitting a warning in the logs.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1266982
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
Add qemuDomainHasVCpuPids to do the checking and replace in place checks
with it.
We no longer need checking whether the thread contains fake data
(vcpupids[0] == vm->pid) as in b07f3d821d
and 65686e5a81 this was removed.
Often when debugging bug reports one is given a copy of the file
from /var/log/libvirt/qemu/$NAME.log along with other supporting
files. In a number of cases I've been given sets of files which
were from different machines. Including the hostname in the QEMU
log file will help identify when the bug reporter is providing
bad information.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
If VM A is shutdown a by qemu agent at appoximately the same time
an agent EOF of VM A happened, there's a chance that deadlock may occur:
qemuProcessHandleAgentEOF in main thread
A) priv->agent = NULL; //A happened before B
//deadlock when we get agent lock which's held by worker thread
qemuAgentClose(agent);
qemuDomainObjExitAgent called by qemuDomainShutdownFlags in worker thread
B) hasRefs = virObjectUnref(priv->agent); // priv->agent is NULL,
// return false
if (hasRefs)
virObjectUnlock(priv->agent); //agent lock will not be released here
In order to resolve, during EOF close the agent first, then set priv->agent
to NULL to fix the deadlock.
This essentially reverts commit id '1020a504'. It's also of note that commit
id '362d0477' notes a possible/rare deadlock similar to what was seen in
the monitor in commit id '25f582e3'. However, it seems interceding changes
including commit id 'd960d06f' should remove the deadlock issue.
With this change, if EOF is called:
Get VM lock
Check if !priv->agent || priv->beingDestroyed, then unlock VM
Call qemuAgentClose
Unlock VM
When qemuAgentClose is called
Get Agent lock
If Agent->fd open, close it
Unlock Agent
Unref Agent
qemuDomainObjEnterAgent
Enter with VM lock
Get Agent lock
Increase Agent refcnt
Unlock VM
After running agent command, calling qemuDomainObjExitAgent
Enter with Agent lock
Unref Agent
If not last reference, unlock Agent
Get VM lock
If we were in the middle of an EnterAgent, call Agent command, and
ExitAgent sequence and the EOF code is triggered, then the EOF code
can get the VM lock, make it's checks against !priv->agent ||
priv->beingDestroyed, and call qemuAgentClose. The CloseAgent
would wait to get agent lock. The other thread then will eventually
call ExitAgent, release the Agent lock and unref the Agent. Once
ExitAgent releases the Agent lock, AgentClose will get the Agent
Agent lock, close the fd, unlock the agent, and unref the agent.
The final unref would cause deletion of the agent.
Signed-off-by: Wang Yufei <james.wangyufei@huawei.com>
Reviewed-by: Ren Guannan <renguannan@huawei.com>
Currently the QEMU monitor is given an FD to the logfile. This
won't work in the future with virtlogd, so it needs to use the
qemuDomainLogContextPtr instead, but it shouldn't directly
access that object either. So define a callback that the
monitor can use for reporting errors from the log file.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
When the qemuProcessAttach/Stop methods write a marker into
the log file, they can use qemuDomainLogContextWrite to
write a formatted message.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Instead of writing directly to a log file descriptor, change
qemuLogOperation to use qemuDomainLogContextWrite().
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The qemuDomainTaint APIs currently expect to be passed a log file
descriptor. Change them to instead use a qemuDomainLogContextPtr
to hide the implementation details.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Convert the places which create/open log files to use the new
qemuDomainLogContextPtr object instead.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
There are two pretty similar functions qemuProcessReadLog and
qemuProcessReadChildErrors. Both read from the QEMU log file
and try to strip out libvirt messages. The latter then reports
an error, while the former lets the callers report an error.
Re-write qemuProcessReadLog so that it uses a single read
into a dynamically allocated buffer. Then introduce a new
qemuProcessReportLogError that calls qemuProcessReadLog
and reports an error.
Convert all callers to use qemuProcessReportLogError.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Once qemuProcessInit was called, qemuProcessLaunch will launch a new
QEMU process with stopped virtual CPUs.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
qemuProcessStart is going to be split in three parts: qemuProcessInit,
qemuProcessLaunch, and qemuProcessFinish so that migration Prepare phase
can insert additional code in the process. qemuProcessStart will be a
small wrapper for all other callers.
qemuProcessInit prepares the domain up to the point when priv->qemuCaps
is initialized.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Now that new domains are started inside a QEMU_ASYNC_JOB_START job,
we need to pass it down to qemuProcessStartCPUs too.
This removes the warning:
qemuDomainObjEnterMonitorInternal:1750 : This thread seems to be the
async job owner; entering monitor without asking for a nested job is
dangerous
Introduced by commit 04c721f, before that this code path was only
executed with QEMU_ASYNC_JOB_NONE.
(This code is not executed on migration, because qemuMigrationPrepareAny
sets the VIR_QEMU_PROCESS_START_PAUSED flag.)
Remembering to call qemuMonitorSetDomainLog in the right paths before
calling qemuProcessStop is annoying and easy to forget. And I already
forgot to do so in commit v1.2.8-52-g0389060: logfd may be leaked if
QEMU process dies between Prepare and Finish migration phases.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
qemuProcessStart is so big that any nontrivial code should be moved to
dedicated functions to make the code easier to read and maintain.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
qemuProcessStart is so big that any nontrivial code should be moved to
dedicated functions to make the code easier to read and maintain.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
qemuProcessStart is so big that any nontrivial code should be moved to
dedicated functions to make the code easier to read and maintain.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
qemuProcessStart is so big that any nontrivial code should be moved to
dedicated functions to make the code easier to read and maintain.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Traditionally, we pass incoming migration URI on QEMU command line,
which has some drawbacks. Depending on the URI QEMU may initialize its
migration state immediately without giving us a chance to set any
additional migration parameters (this applies mainly for fd: URIs). For
some URIs the monitor may be completely blocked from the beginning until
migration is finished, which means we may be stuck in qmp_capabilities
command without being able to send any QMP commands.
QEMU solved this by introducing "defer" parameter for -incoming command
line option. This will tell QEMU to prepare for an incoming migration
while the actual incoming URI is sent using migrate-incoming QMP
command. Before calling this command we can normally talk to the
monitor and even set any migration parameters which will be honored by
the incoming migration.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
We only started an async job for incoming migration from another host.
When we were starting a domain from scratch or restoring from a saved
state (migration from file) we didn't set any async job. Let's introduce
a new QEMU_ASYNC_JOB_START for these cases.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Incoming migration may require quite a few parameters (URI, fd, path) to
be considered while starting QEMU and we will soon add another one.
Let's group all of them in a single struct.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Make callers of qemuBuildCommandLine responsible for providing the URI
which should be passed as a parameter for -incoming.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
As of QEMU 0.11.0 the 'info chardev' monitor command can be
used to report on allocated chardev paths, so we can drop
support for parsing QEMU stderr to locate the PTY paths.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
nodeset should be freed in both success and failure paths.
While tmppath is freed immediately after it's consumed, moving it from
error to cleanup label is a bit more consistent and robust.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
