Originally most of libvirt domain-specific calls were blocking
during a migration.
A new mechanism to allow specific calls (blkstat/blkinfo) to be
executed in such condition has been implemented.
In the long term it'd be desirable to get a more general
solution to mark further APIs as migration safe, without needing
special case code.
* src/qemu/qemu_migration.c: add some additional job signal
flags for doing blkstat/blkinfo during a migration
* src/qemu/qemu_domain.c: add a condition variable that can be
used to efficiently wait for the migration code to clear the
signal flag
* src/qemu/qemu_driver.c: execute blkstat/blkinfo using the
job signal flags during migration
When modifying the disk devices of a live domain and the domain
configuration, the function qemuDomainAttachDeviceConfig
first sets dev->data->disk to NULL. Later qemuDomainAttachDeviceLive
accesses dev->data.disk and causes a segfault.
* src/qemu/qemu_driver.c: fix qemuDomainModifyDeviceFlags() accordingly
The current virDomainMigrateFinish3 method signature attempts to
distinguish two types of errors, by allowing return with ret== 0,
but ddomain == NULL, to indicate a failure to start the guest.
This is flawed, because when ret == 0, there is no way for the
virErrorPtr details to be sent back to the client.
Change the signature of virDomainMigrateFinish3 so it simply
returns a virDomainPtr, in the same way as virDomainMigrateFinish2
The disk locking code will protect against the only possible
failure mode this doesn't account for (loosing conenctivity to
libvirtd after Finish3 starts the CPUs, but before the client
sees the reply for Finish3).
* src/driver.h, src/libvirt.c, src/libvirt_internal.h: Change
virDomainMigrateFinish3 to return a virDomainPtr instead of int
* src/remote/remote_driver.c, src/remote/remote_protocol.x,
daemon/remote.c, src/qemu/qemu_driver.c, src/qemu/qemu_migration.c:
Update for API change
When doing migration, if an error occurs in Perform, it must not
be overwritten during Finish/Confirm steps. If an error occurs
in Finish, it must not be overwritten in Confirm.
Previous commit a9d12c2444e43a0d3e5135eb15b4b62a7c011427 added
code to qemudDomainMigrateFinish2 to preserve the error. This
is not the right place, because it is not applicable in non-p2p
migration. The src/libvirt.c virDomainMigrateV2/3 methods need
code to preserve errors for non-p2p migration, while the
doPeer2PeerMigrate2 and doPeer2PeerMigrate3 methods contain
code to preverse errors for p2p migration.
Remove the bogus error preservation from qemudDomainMigrateFinish2
and qemudDomainMigrateFinish3.
Fix virDomainMigrateV3 and doPeer2PeerMigrate3 so that they
preserve any error hit during the Finish3 step, before invoking
Confirm3.
Finally if qemuMigrationFinish fails to resume the CPUs, it must
preserve the error before tearing down the VM, so that VM cleanup
doesn't overwrite it.
* src/libvirt.c: Preserve error before invoking Confirm3
* src/qemu/qemu_driver.c: Remove bogus error preservation
code in qemudDomainMigrateFinish2/qemudDomainMigrateFinish3
* src/qemu/qemu_migration.c: Preserve error before invoking Confirm3
and after resume fails in qemuMigrationFinish.
Even when failing to start CPUs, the finish method was returning
a success result. Fix this so that the QEMU process is killed
off when finish fails under v3 protocol. Also rename the
killOnFinish boolean to 'v3proto' to make it clearer that this
is a tunable based on the migration protocol version
* src/qemu/qemu_driver.c: Update for API change
* src/qemu/qemu_migration.c, src/qemu/qemu_migration.h: Kill
VM in qemuMigrationFinish if failing to start CPUs
The virDomainMigratePerform3 currently has a single URI parameter
whose meaning varies. It is either
- A QEMU migration URI (normal migration)
- A libvirtd connection URI (peer2peer migration)
Unfortunately when using peer2peer migration, without also
using tunnelled migration, it is possible that both URIs are
required.
This adds a second URI parameter to the virDomainMigratePerform3
method, to cope with this scenario. Each parameter how has a fixed
meaning.
NB, there is no way to actually take advantage of this yet,
since virDomainMigrate/virDomainMigrateToURI do not have any
way to provide the 2 separate URIs
* daemon/remote.c, src/remote/remote_driver.c,
src/remote/remote_protocol.x, src/remote_protocol-structs: Add
the second URI parameter to perform3 message
* src/driver.h, src/libvirt.c, src/libvirt_internal.h: Add
the second URI parameter to Perform3 method
* src/libvirt_internal.h, src/qemu/qemu_migration.c,
src/qemu/qemu_migration.h: Update to handle URIs correctly
This extends the v3 migration protocol such that the
virDomainMigrateBegin3 and virDomainMigratePerform3
methods accept an application supplied XML config for
the target VM.
If the 'xmlin' parameter is NULL, then Begin3 uses the
current guest XML as normal. A driver implementing the
Begin3 method should either reject all non-NULL 'xmlin'
parameters, or strictly validate that the app supplied
XML does not change guest ABI.
The Perform3 method also needed the xmlin parameter to
cope with the Peer2Peer migration sequence.
NB it is not yet possible to use this capability since
neither of the public virDomainMigrate/virDomainMigrateToURI
methods have a way to pass in XML.
* daemon/remote.c, src/remote/remote_driver.c,
src/remote/remote_protocol.x, src/remote_protocol-structs:
Add 'remote_string xmlin' parameter to begin3/perform3
RPC messages
* src/libvirt.c, src/driver.h, src/libvirt_internal.h: Add
'const char *xmlin' parameter to Begin3/Perform3 methods
* src/qemu/qemu_driver.c, src/qemu/qemu_migration.c,
src/qemu/qemu_migration.h: Pass xmlin parameter around
migration methods
Saving domain to previously created file changes also its ownership.
This is certainly not what users want if some conditions are met:
it is a regular, local file and dynamic_ownership is off.
The qemuMigrationConfirm method shouldn't deal with final VM
cleanup, since it can be called from the peer2peer migration,
which expects to still use the 'vm' object afterwards.
Push the cleanup code out of qemuMigrationConfirm, into its
caller, qemuDomainMigrateConfirm3
* src/qemu/qemu_driver.c: Add VM cleanup code to
qemuDomainMigrateConfirm3
* src/qemu/qemu_migration.c, src/qemu/qemu_migration.h: Remove
job handling cleanup from qemuMigrationConfirm
Otherwise qemu is unable to write to it, with the error:
libvir: QEMU error : internal error unable to execute QEMU command 'memsave': Could not open '/var/cache/libvirt/qemu/qemu.mem.RRNvLv'
The v2 migration protocol had a limit on cookie length that was
too small to be useful for QEMU. Avoid generating cookies with
v2 protocol, so that old libvirtd can still reliably migrate a
guest to new libvirtd uses v2 protocol.
* src/qemu/qemu_driver.c: Avoid migration cookies with v2
migration
Improve invalid argument checks in the size query case. The drivers already
relied on this unchecked behavior.
Relax the implementation of virDomainGet(Memory|Blkio)MemoryParameters
in the drivers and allow to pass more memory than necessary for all
parameters.
params and nparams are essential and cannot be NULL. Check this in
libvirt.c and remove redundant checks from the drivers (e.g. xend).
Instead of enforcing that nparams must point to exact same value as
returned by virDomainGetSchedulerType relax this to a lower bound
check. This is what some drivers (e.g. xen hypervisor and esx)
already did. Other drivers (e.g. xend) didn't check nparams at all
and assumed that there is enough space in params.
Unify the behavior in all drivers to a lower bound check and update
nparams to the number of valid values in params on success.
Implement the v3 migration protocol, which has two extra
steps, 'begin' on the source host and 'confirm' on the
source host. All other methods also gain both input and
output cookies to allow bi-directional data passing at
all stages.
The QEMU peer2peer migration method gains another impl
to provide the v3 migration. This finally allows migration
cookies to work with tunnelled migration, which is required
for Spice seamless migration & the lock manager transfer
* src/qemu/qemu_driver.c: Wire up migrate v3 APIs
* src/qemu/qemu_migration.c, src/qemu/qemu_migration.h: Add
begin & confirm methods, and peer2peer impl of v3
The migration protocol has support for a 'cookie' parameter which
is an opaque array of bytes as far as libvirt is concerned. Drivers
may use this for passing around arbitrary extra data they might
need during migration. The QEMU driver needs to do a few things:
- Pass hostname/uuid to allow strict protection against localhost
migration attempts
- Pass SPICE/VNC server port from the target back to the source to
allow seamless relocation of client sessions
- Pass lock driver state from source to destination
This patch introduces the basic glue for handling cookies
but only includes the host/guest UUID & name.
* src/libvirt_private.syms: Export virXMLParseStrHelper
* src/qemu/qemu_migration.c, src/qemu/qemu_migration.h: Parsing
and formatting of migration cookies
* src/qemu/qemu_driver.c: Pass in cookie parameters where possible
* src/remote/remote_protocol.h, src/remote/remote_protocol.x: Change
cookie max length to 16384 bytes
Change all the driver struct initializers to use the
C99 style, leaving out unused fields. This will make
it possible to add new APIs without changing every
driver. eg change:
qemudDomainResume, /* domainResume */
qemudDomainShutdown, /* domainShutdown */
NULL, /* domainReboot */
qemudDomainDestroy, /* domainDestroy */
to
.domainResume = qemudDomainResume,
.domainShutdown = qemudDomainShutdown,
.domainDestroy = qemudDomainDestroy,
And get rid of any existing C99 style initializersr which
set NULL, eg change
.listPools = vboxStorageListPools,
.numOfDefinedPools = NULL,
.listDefinedPools = NULL,
.findPoolSources = NULL,
.poolLookupByName = vboxStoragePoolLookupByName,
to
.listPools = vboxStorageListPools,
.poolLookupByName = vboxStoragePoolLookupByName,
Fix some driver names:
s/virDrvCPUCompare/virDrvCompareCPU/
s/virDrvCPUBaseline/virDrvBaselineCPU/
s/virDrvQemuDomainMonitorCommand/virDrvDomainQemuMonitorCommand/
s/virDrvSecretNumOfSecrets/virDrvNumOfSecrets/
s/virDrvSecretListSecrets/virDrvListSecrets/
And some driver struct field names:
s/getFreeMemory/nodeGetFreeMemory/
Only in drivers which use virDomainObj, drivers that query hypervisor
for domain status need to be updated separately in case their hypervisor
supports this functionality.
The reason is also saved into domain state XML so if a domain is not
running (i.e., no state XML exists) the reason will be lost by libvirtd
restart. I think this is an acceptable limitation.
This is needed if we want to transfer a temporary file. If the
transfer is done with iohelper, we might run into a race condition,
where we unlink() file before iohelper is executed.
* src/fdstream.c, src/fdstream.h,
src/util/iohelper.c: Add new option
* src/lxc/lxc_driver.c, src/qemu/qemu_driver.c,
src/storage/storage_driver.c, src/uml/uml_driver.c,
src/xen/xen_driver.c: Expand existing function calls
We were 31/73 on whether to translate; since less than 50% translated
and since VIR_INFO is less than VIR_WARN which also doesn't translate,
this makes sense.
* cfg.mk (sc_prohibit_gettext_markup): Add VIR_INFO, since it
falls between WARN and DEBUG.
* daemon/libvirtd.c (qemudDispatchSignalEvent, remoteCheckAccess)
(qemudDispatchServer): Adjust offenders.
* daemon/remote.c (remoteDispatchAuthPolkit): Likewise.
* src/network/bridge_driver.c (networkReloadIptablesRules)
(networkStartNetworkDaemon, networkShutdownNetworkDaemon)
(networkCreate, networkDefine, networkUndefine): Likewise.
* src/qemu/qemu_driver.c (qemudDomainDefine)
(qemudDomainUndefine): Likewise.
* src/storage/storage_driver.c (storagePoolCreate)
(storagePoolDefine, storagePoolUndefine, storagePoolStart)
(storagePoolDestroy, storagePoolDelete, storageVolumeCreateXML)
(storageVolumeCreateXMLFrom, storageVolumeDelete): Likewise.
* src/util/bridge.c (brProbeVnetHdr): Likewise.
* po/POTFILES.in: Drop src/util/bridge.c.
These VIR_XXXX0 APIs make us confused, use the non-0-suffix APIs instead.
How do these coversions works? The magic is using the gcc extension of ##.
When __VA_ARGS__ is empty, "##" will swallow the "," in "fmt," to
avoid compile error.
example: origin after CPP
high_level_api("%d", a_int) low_level_api("%d", a_int)
high_level_api("a string") low_level_api("a string")
About 400 conversions.
8 special conversions:
VIR_XXXX0("") -> VIR_XXXX("msg") (avoid empty format) 2 conversions
VIR_XXXX0(string_literal_with_%) -> VIR_XXXX(%->%%) 0 conversions
VIR_XXXX0(non_string_literal) -> VIR_XXXX("%s", non_string_literal)
(for security) 6 conversions
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Introduce a virProcessKill function that can be safely called
even when the job mutex is held. This allows virDomainDestroy
to kill any VM even if it is asleep in a monitor job. The PID
will die and the thread asleep on the monitor will then wake
up releasing the job mutex.
* src/qemu/qemu_driver.c: Kill process before using qemuProcessStop
to ensure job is released
* src/qemu/qemu_process.c: Add virProcessKill for killing off
QEMU processes
This matches the public API and helps to get rid of some special
case code in the remote generator.
Rename driver API functions and XDR protocol structs.
No functional change included outside of the remote generator.
As well as taint warnings going to the main libvirt log,
add taint warnings to the per-domain logfile
Domain id=3 is tainted: high-privileges
Domain id=3 is tainted: disk-probing
Domain id=3 is tainted: shell-scripts
Domain id=3 is tainted: custom-monitor
* src/qemu/qemu_domain.c, src/qemu/qemu_domain.h: Enhance
qemuDomainTaint to also log to the domain logfile
* src/qemu/qemu_driver.c: Pass -1 for logFD to taint methods to
auto-append to logfile
* src/qemu/qemu_process.c: Pass open logFD at startup for taint
methods
Wire up logging of VM tainting to the QEMU driver
- If running QEMU as root user/group or without capabilities
being cleared
- If passing custom QEMU command line args
- If issuing custom QEMU monitor commands
- If using a network interface config with an associated
shell script
- If using a disk config relying on format probing
The warnings, per-VM appear in the main libvirtd logs
11:56:17.571: 10832: warning : qemuDomainObjTaint:712 : Domain id=1 name='l2' uuid=c7a3edbd-edaf-9455-926a-d65c16db1802 is tainted: high-privileges
11:56:17.571: 10832: warning : qemuDomainObjTaint:712 : Domain id=1 name='l2' uuid=c7a3edbd-edaf-9455-926a-d65c16db1802 is tainted: disk-probing
The taint flags are reset when the VM is stopped.
* src/qemu/qemu_domain.c, src/qemu/qemu_domain.h: Helper APIs
for logging taint warnings
* src/qemu/qemu_driver.c: Log tainting with custom QEMU monitor
commands and disk/net hotplug with unsupported configs
* src/qemu/qemu_process.c: Log tainting at startup based on
unsupported configs
Clang 2.8 wasn't quite able to follow that persistentDef was
assigned earlier if (flags & VIR_DOMAIN_MEM_CONFIG) is true.
Silence this false positive, to make clang analysis easier to use.
* src/qemu/qemu_driver.c (qemudDomainSetMemoryFlags): Add an
annotation to silence clang's claim of a NULL dereference.
This code has had problems historically. As originally
written, in commit 6bcf2501 (Jun 08), it could call unlink
on a random string, nuking an unrelated file.
Then commit 182a80b9 (Sep 09), the code was rewritten to
allocate tmp, with both a use-after-free bug and a chance to
call unlink(NULL).
Commit e206946 (Mar 11) fixed the use-after-free, but not the
NULL dereference. Thanks to clang for catching this!
* src/qemu/qemu_driver.c (qemudDomainMemoryPeek): Don't call
unlink on NULL.
This commit fixes
qemu/qemu_driver.c: In function 'qemuDomainModifyDeviceFlags':
qemu/qemu_driver.c:4041:8: warning: 'ret' may be used uninitialized in this
function [-Wuninitialized]
qemu/qemu_driver.c:4013:9: note: 'ret' was declared here
The variable is set to -1 so that the error paths are taken when the code
to set it didn't get a chance to run. Without initializing it, we could
return some an undefined value from this function.
While I was at it, I made a trivial whitespace change in the same function
to improve readability.
Support update of disks by MODIFY_CONFIG
This patch includes changes for qemu's disk to support
virDomainUpdateDeviceFlags() with VIR_DOMAIN_DEVICE_MODIFY_CONFIG.
This patch adds support for CDROM/foppy disk types.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
* src/qemu/qemu_driver.c
(qemuDomainUpdateDeviceConfig): support cdrom/floppy.
Support changes of disks by MODIFY_CONFIG for qemu.
This patch includes patches for qemu's disk to support
virDomainAt(De)tachDeviceFlags with VIR_DOMAIN_DEVICE_MODIFY_CONFIG.
Other devices can be added incrementally.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
* /src/conf/domain_conf.c
(virDomainDiskIndexByName): returns array index of disk in vmdef.
(virDomainDiskRemoveByName): removes a disk which has the name in vmdef.
* src/qemu/qemu_driver.c
(qemuDomainAttachDeviceConfig): add support for Disks.
(qemuDomainDetachDeviceConfig): add support for Disks.
This patch adds functions for modify domain's persistent definition.
To do error recovery in easy way, we use a copy of vmdef and update it.
The whole sequence will be:
make a copy of domain definition.
if (flags & MODIFY_CONFIG)
update copied domain definition
if (flags & MODIF_LIVE)
do hotplug.
if (no error)
save copied one to the file and update cached definition.
else
discard copied definition.
This patch is mixuture of Eric Blake's work and mine.
From: Eric Blake <eblake@redhat.com>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
(virDomainObjCopyPersistentDef): make a copy of persistent vm definition
(qemuDomainAttach/Detach/UpdateDeviceConfig) : callbacks. now empty
(qemuDomainModifyDeviceFlags): add support for MODIFY_CONFIG and MODIFY_CURRENT
This patch strips reusable part of qemuDomainUpdateDeviceFlags()
and consolidate it to qemuDomainModifyDeviceFlags().
No functional changes.
* src/qemu/qemu_driver.c
(qemuDomainChangeDiskMediaLive) : pulled out code for updating disks.
(qemuDomainUpdateDeviceLive) : core of UpdateDevice, extracted from
UpdateDeviceFlags()
(qemuDomainModifyDeviceFlags): add support for updating device in live domain.
(qemuDomainUpdateDeviceFlags): reworked as a wrapper function of
qemuDomainModifyDeviceFlags()
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
clean up At(De)tachDeviceFlags() for consolidation.
qemuDomainAttachDeviceFlags()/qemuDomainDetachFlags()/
qemuDomainUpdateDeviceFlags() has similar logics and copied codes.
This patch series tries to unify them to use shared code when it can.
At first, clean up At(De)tachDeviceFlags() and devide it into functions.
By this, this patch pulls out shared components between functions.
Based on patch series by Eric Blake, I added some modification as
switch-case with QEMU_DEVICE_ATTACH, QEMU_DEVICE_DETACH, QEMU_DEVICE_UPDATE
* src/qemu/qemu_driver.c
(qemuDomainAt(De)tachDeviceFlags) : pulled out to qemuDomainModifyDeviceFlags()
(qemuDomainModifyDeviceFlags) : implements generic code for modifying domain.
(qemuDomainAt(De)tachDeviceFlagsLive) : code for at(de)taching devices to
domain in line. no changes in logic from old code.
(qemuDomainAt(De)tachDeviceDiskLive) : for at(de)taching Disks.
(qemuDomainAt(De)tachDeviceControllerLive) : for at(de)taching Controllers
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Centralize device modification in the more flexible APIs, to allow future
honoring of additional flags. Explicitly reject the
VIR_DOMAIN_DEVICE_MODIFY_FORCE flag on attach/detach.
Based on Eric Blake<eblake@redhat.com>'s work.
* src/qemu/qemu_driver.c
(qemudDomainAttachDevice)(qemudDomainAttachDeviceFlags): Swap bodies,rename...
(qemudDomainDetachDevice, qemudDomainDetachDeviceFlags): Likewise.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
This patch does the following two things:
1. hold an extra reference while handling watchdog event
If the domain is not persistent, and qemu quits unexpectedly before
calling processWatchdogEvent(), vm will be freed and the function
processWatchdogEvent() will be dangerous.
2. unlock qemu driver and vm before returning from processWatchdogEvent()
When the function processWatchdogEvent() failed, we only free wdEvent,
but forget to unlock qemu driver and vm, free dumpfile.
We do not lock qemu_driver when calling virThreadPoolNew(). If it failed,
we will unlock qemu_driver. It is dangerous.
We may use this pool during auto starting domains. So we must create it before
calling qemuAutostartDomains(). Otherwise, libvirtd will crash.
This patch enables the migration of Qemu VMs between hosts of different endianess. I tested this by migrating a i686 VM between a x86 and ppc64 host.
I am converting the 'int's in the VM's state header to uint32_t assuming this doesn't break compatibility with existing deployments other than Linux.
