Any method which intends to invoke a monitor command must have
a check for virDomainObjIsActive() before using the monitor to
ensure that priv->mon != NULL.
There is one subtle edge case in this though. If a method invokes
multiple monitor commands, and calls qemuDomainObjExitMonitor()
in between two of these commands then there is no guarentee that
priv->mon != NULL anymore. This is because the QEMU process may
exit or die at any time, and because qemuDomainObjEnterMonitor()
releases the lock on virDomainObj, it is possible for the background
thread to close the monitor handle and thus qemuDomainObjExitMonitor
will release the last reference allowing priv->mon to become NULL.
This affects several methods, most notably migration but also some
hotplug methods. This patch takes a variety of approaches to solve
the problem, depending on the particular usage scenario. Generally
though it suffices to add an extra virDomainObjIsActive() check
if qemuDomainObjExitMonitor() was called during the method.
* src/qemu/qemu_driver.c: Fix multiple potential NULL pointer flaws
in usage of the monitor
* src/qemu/qemu_driver.c (qemudDomainSetVcpus): Upon look-up failure,
i.e., vm==NULL, goto cleanup, rather than to "endjob", superficially
since the latter would dereference vm, but more fundamentally because
we certainly don't want to call qemuDomainObjEndJob before we've
even attempted qemuDomainObjBeginJob.
(gdb) p/x QEMUD_CMD_FLAG_VNET_HOST
$7 = 0xffffffff80000000
Oops - that meant we were incorrectly setting QEMU_CMD_FLAG_RTC_TD_HACK
for qemu-kvm-0.12.3 (and probably botching a few other settings as well).
Fixes Red Hat BZ#592070
* src/qemu/qemu_conf.h (QEMUD_CMD_FLAG_VNET_HOST): Avoid sign
extension.
* tests/qemuhelpdata/qemu-kvm-0.12.3: New file.
* tests/qemuhelptest.c (mymain): Add another case.
A fedora translator filed:
https://bugzilla.redhat.com/show_bug.cgi?id=580816
Pointing out these two error messages as unclear: "write save" sounds
like a typo without context, and lack of a colon made the second message
difficult to parse.
virFileResolveLink was returning a positive value on error,
thus confusing callers that assumed failure was < 0. The
confusion is further evidenced by callers that would have
ended up calling virReportSystemError with a negative value
instead of a valid errno.
Fixes Red Hat BZ #591363.
* src/util/util.c (virFileResolveLink): Live up to documentation.
* src/qemu/qemu_security_dac.c
(qemuSecurityDACRestoreSecurityFileLabel): Adjust callers.
* src/security/security_selinux.c
(SELinuxRestoreSecurityFileLabel): Likewise.
* src/storage/storage_backend_disk.c
(virStorageBackendDiskDeleteVol): Likewise.
Fix the cygwin regression introduced in commit 48445ccff, but
without repeating the fresh build regression of commit
2d550542e.
* src/Makefile.am (libvirt_test_la_LIBADD): Split out subset of
locally-built libraries...
(libvirt_test_la_BUILT_LIBADD): ...into new variable.
(libvirt_test_la_DEPENDENCIES): Depend only on the subset that
automake would have given us for free if we didn't have to add our
own extra file.
Matthias noted that the line:
virt_aa_helper_LDFLAGS = $(WARN_CFLAGS)
looks inconsistent, so I did an audit.
Currently, the set of compiler warning flags passed to gcc as $CC are
equally permitted as the set of linker flags passed to gcc as $LD, so
there was no problem with that usage. But if we ever get in a
situation where $CC and $LD treat particular flags differently, using
the right variable form will make it easier.
In the process, I spotted a couple of typos that were omitting useful
flags, as well as specifying a -l under the wrong variable.
* acinclude.m4 (LIBVIRT_COMPILE_WARNINGS): Define WARN_LDFLAGS as
an alias for WARN_CFLAGS.
* tools/Makefile.am (virsh_LDFLAGS): Use more canonical spelling.
* proxy/Makefile.am (libvirt_proxy_LDFLAGS): Likewise. Move
library...
(libvirt_proxy_LDADD): ...here.
* src/Makefile.am (virt_aa_helper_LDFLAGS): Use more canonical
spelling of WARN_LDFLAGS.
(libvirt_parthelper_LDFLAGS, libvirt_lxc_LDFLAGS): Likewise. Use
correct spelling of COVERAGE_LDFLAGS.
Reported by Matthias Bolte.
* configure.ac: Check for <linux/magic.h>.
* src/util/storage_file.c: Include <linux/magic.h> only if present.
Linux kernels prior to 2.6.19 lacked it.
[__linux__] (NFS_SUPER_MAGIC): Define if not already defined.
qemuReadLogOutput early VM death detection is racy and won't always work.
Startup then errors when connecting to the VM monitor. This won't report
the emulator cmdline output which is typically the most useful diagnostic.
Check if the VM has died at the very end of the monitor connection step,
and if so, report the cmdline output.
See also: https://bugzilla.redhat.com/show_bug.cgi?id=581381
* src/qemu/qemu_driver.c (qemudDomainSetVcpus): Avoid NULL-deref
upon unknown UUID. Call qemuDomainObjBeginJob(vm) only after
ensuring that vm != NULL, not before. This potential NULL-deref
was introduced by commit 2c555d87b0.
This reverts commit 2d550542ee.
The patch worked for incremental builds, but broke fresh
builds, because it interfered with automake's automatic
dependency generation. Until I figure out how to make
automake do what we want, I'd rather leave cygwin broken
but fresh Linux builds working.
make[3]: *** No rule to make target `-lxml2', needed by `libvirt.la'. Stop.
Due to treating the wrong string as a dependency.
* src/Makefile.am (libvirt_la_DEPENDENCIES): Depend only on
locally-built file, not on strings that might resolve as '-lxml2'.
The code specifies driver->cacheDir as the format string,
but it usually doesn't contain '%s', so the subsequent
argument, "/qemu.mem.XXXXXX", is always ignored.
The patch fixes the misuse.
Setting dynamic_ownership=0 in /etc/libvirt/qemu.conf prevents
libvirt's DAC security driver from setting uid/gid on disk
files when starting/stopping QEMU, allowing the admin to manage
this manually. As a side effect it also stopped setting of
uid/gid when saving guests to a file, which completely breaks
save when QEMU is running non-root. Thus saved state labelling
code must ignore the dynamic_ownership parameter
* src/qemu/qemu_security_dac.c: Ignore dynamic_ownership=0 when
doing save/restore image labelling
When QEMU runs with its disk on NFS, and as a non-root user, the
disk is chownd to that non-root user. When migration completes
the last step is shutting down the QEMU on the source host. THis
normally resets user/group/security label. This is bad when the
VM was just migrated because the file is still in use on the dest
host. It is thus neccessary to skip the reset step for any files
found to be on a shared filesystem
* src/libvirt_private.syms: Export virStorageFileIsSharedFS
* src/util/storage_file.c, src/util/storage_file.h: Add a new
method virStorageFileIsSharedFS() to determine if a file is
on a shared filesystem (NFS, GFS, OCFS2, etc)
* src/qemu/qemu_driver.c: Tell security driver not to reset
disk labels on migration completion
* src/qemu/qemu_security_dac.c, src/qemu/qemu_security_stacked.c,
src/security/security_selinux.c, src/security/security_driver.h,
src/security/security_apparmor.c: Add ability to skip disk
restore step for files on shared filesystems.
The cgroups ACL code was only allowing the primary disk image.
It is possible to chain images together, so we need to search
for backing stores and add them to the ACL too. Since the ACL
only handles block devices, we ignore the EINVAL we get from
plain files. In addition it was missing code to teardown the
cgroup when hot-unplugging a disk
* src/qemu/qemu_driver.c: Allow backing stores in cgroup ACLs
and add missing teardown code in unplug path
If the IO error event does not include a reason, then there
is a possible crash dispatching the event
* src/conf/domain_event.c: Missing check for a NULL reason before
strduping allows for a crash
QEMU is gaining a new monitor command netdev_add for hotplugging
NICs using the netdev backend code. We already support this on
the command this, though it is disabled. This adds support for
hotplug too, also to remain disabled until 0.13 QEMU is released
* src/qemu/qemu_driver.c: Support netdev hotplug for NICs
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h,
src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h: Add
support for netdev_add and netdev_remove commands
When closing a monitor using qemuMonitorClose(), we are aware of
the possibility the monitor is still being used somewhere:
/* NB: ordinarily one might immediately set mon->watch to -1
* and mon->fd to -1, but there may be a callback active
* that is still relying on these fields being valid. So
* we merely close them, but not clear their values and
* use this explicit 'closed' flag to track this state */
but since we call virEventAddHandle() on that monitor without increasing
its ref counter, the monitor is still freed which makes possible users
of it quite unhappy. The unhappiness can lead to a hang if qemuMonitorIO
tries to lock mutex which no longer exists.
First calling REMOTE_PROC_CLOSE and then removing watches might lead to
a hang as HANGUP event can be triggered before the watches are actually
removed but after virConnectPtr is already freed. As a result of that
remoteDomainEventFired() would try to lock uninitialized mutex, which
would hang for ever.
Allow debugging of GNUTLS interactions by setting
LIBVIRT_GNUTLS_DEBUG=10 LIBVIRT_DEBUG=1 virsh
* src/remote/remote_driver.c: Use LIBVIRT_GNUTLS_DEBUG to
enable gnutls debugging
Some shells warn about missing programs before redirection;
the idiomatic way to silence them is to run the program check
inside a subshell, with the redirections outside the subshell.
But a subshell is only needed in places where it is reasonable
to expect the use of such a noisy shell in the first place.
* src/Makefile.am (remote_protocol-structs): Use subshell, for
FreeBSD 8.0 /bin/sh.
* cfg.mk (sc_preprocessor_indentation): Avoid subshell, since the
only users running cfg.mk can be assumed to have decent tools.
For printf("%*s",foo,bar), clang complains if foo is not int:
warning: field width should have type 'int', but argument has
type 'unsigned int' [-Wformat]
* src/conf/storage_encryption_conf.c
(virStorageEncryptionSecretFormat, virStorageEncryptionFormat):
Use correct type.
* src/conf/storage_encryption_conf.h (virStorageEncryptionFormat):
Likewise.
Now, if you update remote_protocol.x without also updating
remote_protocol-structs to match, then "make check" will fail.
* src/Makefile.am (remote_protocol-structs): Extract list of
structs and member names from remote_protocol.o.
(check-local): Depend on it.
* src/remote_protocol-structs: New file.
This reverts commit b5b8a6db69.
That commit was not necessary. The problem is fixed by commit
0e9b3a269b, but I didn't rebuild
it properly after pulling in the commit and didn't notice it.
Per automake, LDFLAGS is used early in the line, and LIBADD
(libraries) or LDADD (programs) is used late. On platforms like
cygwin, without lazy linking, this order matters. Therefore, libtool
commands, -L, and similar should be in LDFLAGS, but -l should be in
L*ADD.
* src/Makefile.am (*_LDFLAGS): Move libraries...
(*_LIBADD): ...to their LIBADD counterpart.
Change 965466c1 added a new field to struct remote_error, which broke
the RPC protocol. Fortunately the new field is unused, so this change
simply removes it again.
* src/remote/remote_protocol.(c|h|x): Remove remote_nwfilter from struct
remote_error
With the introduction of the generic qemu device model, unplugging
SCSI disks works like a charm, so support it in libvirt.
* src/qemu/qemu_driver.c: Add qemudDomainDetachSCSIDiskDevice() to do the
unplugging, extend qemudDomainDetachDeviceAdd().
Signed-off-by: Wolfgang Mauerer <wolfgang.mauerer@siemens.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Gnulib can guarantee that pthread.h exists, but for now, it is a dummy
header with no support for most pthread_* functions. Modify our
use of pthread to use function checks, rather than header checks,
to determine how much pthread support is present.
* bootstrap.conf (gnulib_modules): Add pthread.
* configure.ac: Drop all pthread.h checks. Optimize function
checks. Add check for pthread functions.
* src/Makefile.am (libvirt_lxc_LDADD): Ensure proper link.
* src/remote/remote_driver.c (remoteIOEventLoop): Depend on
pthread_sigmask, now that gnulib guarantees pthread.h.
* src/util/util.c (virFork): Likewise.
* src/util/threads.c (threads-pthread.c): Depend on
pthread_mutexattr_init, as a witness of full pthread support.
* src/util/threads.h (threads-pthread.h): Likewise.
Detected by clang. POSIX requires that the second argument to
va_start be the name of the last variable; and in some implementations,
passing *path instead of path would dereference bogus memory instead
of pulling arguments off the stack.
* src/util/util.c (virBuildPathInternal): Use correct argument to
va_start.
Support for live migration between hosts that do not share storage was
added to qemu-kvm release 0.12.1.
It supports two flags:
-b migration without shared storage with full disk copy
-i migration without shared storage with incremental copy (same base image
shared between source and destination).
I tested the live migration without shared storage (both flags) for native
and p2p with and without tunnelling. I also verified that the fix doesn't
affect normal migration with shared storage.
Add an empty body for virCondWaitUntil and move virPipeReadUntilEOF
out of the '#ifndef WIN32' block, because it compiles fine with MinGW
in combination with gnulib.
Necessary on cygwin, where uid_t and gid_t are 4-byte long rather
than int, causing gcc -Wformat warnings.
* src/util/util.c (virFileOperationNoFork, virDirCreateNoFork)
(virFileOperation, virDirCreate, virGetUserEnt): Cast uid_t and
gid_t before passing to printf.
* .gitignore: Ignore Windows executables.
When a filter is updated, only those interfaces must have their old
rules cleared that either reference the filter directly or indirectly
through another filter. Remember between the different steps of the
instantiation of the filters which interfaces must be skipped. I am
using a hash map to remember the names of the interfaces and store a
bogus pointer to ~0 into it that need not be freed.
For the decision on whether to instantiate the rules, the check for a
pending IP address learn request is not sufficient since then only the
thread could instantiate the rules. So, a boolean needs to be passed
when the thread instantiates the filter rules late and the IP address
learn request is still pending in order to override the check for the
pending learn request. If the rules are to be updated while the thread
is active, this will not be done immediately but the thread will do that
later on.
WIN32 is always defined when __MINGW32__ is defined, but the
converse is not true. WIN32 is more generic, if someone were
to ever attempt porting to a microsoft compiler. This does
not affect Cygwin, which intentionally does not define WIN32.
* src/qemu/qemu_driver.c (qemuDomainGetBlockInfo): Use more
generic flag macro.
* src/storage/storage_backend.c
(virStorageBackendUpdateVolTargetInfoFD)
(virStorageBackendRunProgRegex): Likewise.
* tools/console.h (vshRunConsole): Likewise.
[Error message]
error: Failed to start domain lxc_test1
error: internal error Failed to create veth device pair: 512
The reason of the failure is that lxc driver unexpectedly re-uses
an auto-assigned veth name and tries to create the created veth
again. The failure will happen when a domain has multiple network
interfaces and the names of those are not specified in XML.
The patch fixes the problem by resetting buffers of veth names
in every iteration of creating veth.
* src/lxc/lxc_driver.c: prevent re-using auto-assigned veth name
Reported by Kumar L Srikanth-B22348.
<hostdev> address parsing previously attempted to detect the number
base: currently it is hardcoded to base 16, which can break PCI
assignment via virt-manager. Revert to the previous behavior.
* src/conf/domain_conf.c: virDomainDevicePCIAddressParseXML, switch to
virStrToLong_ui(bus, NULL, 0, ...) to autodetect base
This introduces a new event type
VIR_DOMAIN_EVENT_ID_IO_ERROR_REASON
This event is the same as the previous VIR_DOMAIN_ID_IO_ERROR
event, but also includes a string describing the cause of
the event.
Thus there is a new callback definition for this event type
typedef void (*virConnectDomainEventIOErrorReasonCallback)(virConnectPtr conn,
virDomainPtr dom,
const char *srcPath,
const char *devAlias,
int action,
const char *reason,
void *opaque);
This is currently wired up to the QEMU block IO error events
* daemon/remote.c: Dispatch IO error events to client
* examples/domain-events/events-c/event-test.c: Watch for
IO error events
* include/libvirt/libvirt.h.in: Define new IO error event ID
and callback signature
* src/conf/domain_event.c, src/conf/domain_event.h,
src/libvirt_private.syms: Extend API to handle IO error events
* src/qemu/qemu_driver.c: Connect to the QEMU monitor event
for block IO errors and emit a libvirt IO error event
* src/remote/remote_driver.c: Receive and dispatch IO error
events to application
* src/remote/remote_protocol.x: Wire protocol definition for
IO error events
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c: Watch for BLOCK_IO_ERROR event
from QEMU monitor
Introduce a function to notify the IP address learning
thread to terminate and thus release the lock on the interface.
Notify the thread before grabbing the lock on the interface
and tearing down the rules. This prevents a 'virsh destroy' to
tear down the rules that the IP address learning thread has
applied.
The functions invoked by the IP address learning thread
that apply some basic filtering rules did not clean up
any previous filtering rules that may still be there
(due to a libvirt restart for example). With the
patch below all the rules are cleaned up first.
Also, I am introducing a function to drop all traffic
in case the IP address learning thread could not apply
the rules.
The local DHCP server on virtbr0 sends DHCP ACK messages when a VM is
started and requests an IP address while the initial DHCP lease on the
VM's MAC address hasn't expired. So, also pick the IP address of the VM
if that type of message is seen.
Thanks to Gerhard Stenzel for providing a test case for this.
Changes from V1 to V2:
- cleanup: replacing DHCP option numbers through constants
When using -device syntax, the IO event will have a different
prefix, 'drive-' that needs to be skipped over before matching
against the libvirt disk alias
* src/qemu/qemu_driver.c: Skip QEMU_DRIVE_HOST_PREFIX in IO event
* daemon/remote.c: Server side dispatcher
* daemon/remote_dispatch_args.h, daemon/remote_dispatch_prototypes.h,
daemon/remote_dispatch_ret.h, daemon/remote_dispatch_table.h: Update
with new API
* src/remote/remote_driver.c: Client side dispatcher
* src/remote/remote_protocol.c, src/remote/remote_protocol.h: Update
* src/remote/remote_protocol.x: Define new wire protocol
This defines the internal driver API and stubs out each driver
* src/driver.h: Define virDrvDomainGetBlockInfo signature
* src/libvirt.c, src/libvirt_public.syms: Glue public API to drivers
* src/esx/esx_driver.c, src/lxc/lxc_driver.c, src/opennebula/one_driver.c,
src/openvz/openvz_driver.c, src/phyp/phyp_driver.c,
src/test/test_driver.c, src/uml/uml_driver.c, src/vbox/vbox_tmpl.c,
src/xen/xen_driver.c, src/xenapi/xenapi_driver.c: Stub out driver
qemuDomainPCIAddressSetFree was freeing up the hash
table for the pci addresses, but not freeing up the addr
structure. Looking over the callers of this function, it
seems like they expect it to also free up the structure,
so do that here.
Signed-off-by: Chris Lalancette <clalance@redhat.com>
We were over-writing a pointer without freeing it in
case of a disk device, leading to a memory leak.
Signed-off-by: Chris Lalancette <clalance@redhat.com>
When building on Ubuntu with make -j3 (or more), it would always
fail when trying to build virt-aa-helper. I'm not an expert in
automake by any means, but I think the entry for virt-aa-helper
is mis-using LDADD; it shouldn't be putting direct paths to
libvirt_conf.la and libvirt_util.la, but instead referencing those
names. With this patch in place, I'm able to successfully build
on Ubuntu 9.04 with make -j3.
Signed-off-by: Chris Lalancette <clalance@redhat.com>
The previous commit changes a goto from 'endjob' to 'cleanup',
leaving the endjob label unused. Remove it to avoid compile
warning.
* src/qemu/qemu_driver.c: Remove 'endjob' label
* src/qemu/qemu_driver.c (qemuDomainSnapshotCreateXML): When setting
"vm" to NULL, jump over vm-dereferencing code to "cleanup".
(qemuDomainRevertToSnapshot): Likewise.
use /var/lib/libvirt/dnsmasq since /var/lib/libvirt/network is
unreadable by the dnsmasq binary
* src/network/bridge_driver.c: update DNSMASQ_STATE_DIR
* src/Makefile.am: create it on make install
* libvirt.spec.in: take the new directory into account
In cases where the security driver failed to restore a label after a
guest has saved, we mistakenly jumped to the error cleanup paths.
This is not good, because the operation has in fact completed and
cannot be rolled back completely. Label restore is non-critical, so
just log the problem instead. Also add a missing restore call in
the error cleanup path
* src/qemu/qemu_driver.c: Fix handling of security driver
restore failures in QEMU domain save
When cgroups is enabled, access to block devices is likely to be
restricted to a whitelist. Prior to saving a guest to a block device,
it is necessary to add the block device to the whitelist. This is
not required upon restore, since QEMU reads from stdin
* src/qemu/qemu_driver.c: Add block device to cgroups whitelist
if neccessary during domain save.
The save process was relying on use of the shell >> append
operator to ensure the save data was placed after the libvirt
header + XML. This doesn't work for block devices though.
Replace this code with use of 'dd' and its 'seek' parameter.
This means that we need to pad the header + XML out to a
multiple of dd block size (in this case we choose 512).
The qemuMonitorMigateToCommand() monitor API is used for both
save/coredump, and migration via UNIX socket. We can't simply
switch this to use 'dd' since this causes problems with the
migration usage. Thus, create a dedicated qemuMonitorMigateToFile
which can accept an filename + offset, and remove the filename
from the current qemuMonitorMigateToCommand() API
* src/qemu/qemu_driver.c: Switch to qemuMonitorMigateToFile
for save and core dump
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h,
src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h: Create
a new qemuMonitorMigateToFile, separate from the existing
qemuMonitorMigateToCommand to allow handling file offsets
It is possible to use block devices with domain save/restore. Upon
failure QEMU unlinks the path being saved to. This isn't good when
it is a block device !
* src/qemu/qemu_driver.c: Don't unlink block devices if save fails
If a transient QEMU crashes during save attempt, then the virDomainPtr
object may be freed. If a persistent QEMU crashes during save, then
the 'priv->mon' field is no longer valid since it will be inactive.
* src/qemu/qemu_driver.c: Fix two crashes when QEMU exits
during a save attempt
In particular I was forgetting to take the qemuMonitorPrivatePtr
lock (via qemuDomainObjBeginJob), which would cause problems
if two users tried to access the same domain at the same time.
This patch also fixes a problem where I was forgetting to remove
a transient domain from the list of domains.
Thanks to Stephen Shaw for pointing out the problem and testing
out the initial patch.
Signed-off-by: Chris Lalancette <clalance@redhat.com>
This patch adds support for the RARP protocol. This may be needed due to
qemu sending out a RARP packet (at least that's what it seems to want to
do even though the protocol id is wrong) when migration finishes and
we'd need a rule to let the packets pass.
Unfortunately my installation of ebtables does not understand -p RARP
and also seems to otherwise depend on strings in /etc/ethertype
translated to protocol identifiers. Therefore I need to pass -p 0x8035
for RARP. To generally get rid of the dependency of that file I switch
all so far supported protocols to use their protocol identifier in the
-p parameter rather than the string.
I am also extending the schema and added a test case.
changes from v1 to v2:
- added test case into patch
With JSON qemu monitor, we get a STOP event from qemu whenever qemu
stops guests CPUs. The downside of it is that vm->state is changed to
PAUSED and a new generic paused event is send to applications. However,
when we ask qemu to stop the CPUs we are not really interested in qemu
event and we usually want to issue a more specific event.
By setting vm->status to PAUSED before actually sending the request to
qemu (and resetting it back if the request fails) we can ignore the
event since the event handler does nothing when the guest is already
paused. This solution is quite hacky but unfortunately it's the best
solution which I was able to come up with and it doesn't introduce a
race condition.
