Commit Graph

8881 Commits

Author SHA1 Message Date
Michal Privoznik
3b94239ffb qemu_driver: Try KVM_CAP_MAX_VCPUS only if defined
With our recent patch (1715c83b5f) we thrive to get the correct
number of maximal VCPUs. However, we are using a constant from
linux/kvm.h which may be not defined in every distro. Hence, we
should guard usage of the constant with ifdef preprocessor
directive. This was introduced in kernel:

    commit 8c3ba334f8588e1d5099f8602cf01897720e0eca
    Author: Sasha Levin <levinsasha928@gmail.com>
    Date:   Mon Jul 18 17:17:15 2011 +0300

    KVM: x86: Raise the hard VCPU count limit

    The patch raises the hard limit of VCPU count to 254.

    This will allow developers to easily work on scalability
    and will allow users to test high VCPU setups easily without
    patching the kernel.

    To prevent possible issues with current setups, KVM_CAP_NR_VCPUS
    now returns the recommended VCPU limit (which is still 64) - this
    should be a safe value for everybody, while a new KVM_CAP_MAX_VCPUS
    returns the hard limit which is now 254.

$ git desc 8c3ba334f
v3.1-rc7-48-g8c3ba33
2013-03-13 14:31:29 +01:00
Peter Krempa
27cf98e2d1 virCaps: conf: start splitting out irrelevat data
The virCaps structure gathered a ton of irrelevant data over time that.
The original reason is that it was propagated to the XML parser
functions.

This patch aims to create a new data structure virDomainXMLConf that
will contain immutable data that are used by the XML parser. This will
allow two things we need:

1) Get rid of the stuff from virCaps

2) Allow us to add callbacks to check and add driver specific stuff
after domain XML is parsed.

This first attempt removes pointers to private data allocation functions
to this new structure and update all callers and function that require
them.
2013-03-13 09:27:14 +01:00
Daniel P. Berrange
be27de6e8d Remove hack using existance of an 'identity' string to disable auth
Currently the server determines whether authentication of clients
is complete, by checking whether an identity is set. This patch
removes that lame hack and replaces it with an explicit method
for changing the client auth code

* daemon/remote.c: Update for new APis
* src/libvirt_private.syms, src/rpc/virnetserverclient.c,
  src/rpc/virnetserverclient.h: Remove virNetServerClientGetIdentity
  and virNetServerClientSetIdentity, adding a new method
  virNetServerClientSetAuth.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-03-12 18:07:17 +00:00
Daniel P. Berrange
a299714295 Add API for thread cancellation
Add a virThreadCancel function. This functional is inherently
dangerous and not something we want to use in general, but
integration with SELinux requires that we provide this stub.
We leave out any Win32 impl to discourage further use and
because obviously SELinux isn't enabled on Win32

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-03-12 18:07:11 +00:00
Daniel P. Berrange
32b7e92db6 Add missing break in LXC loop device setup
When setting up disks with loop devices for LXC, one of the
switch cases was missing a 'break' causing it to fallthrough
to an error condition.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-03-12 11:52:52 +00:00
Jiri Denemark
57bb725aca qemu: Avoid NULL dereference in qemuSharedDiskEntryFree
At least one caller may call qemuSharedDiskEntryFree with NULL as the
first argument. Let's make the function similar to other *Free functions
and do nothing in such case.
2013-03-12 09:10:41 +01:00
Peter Krempa
1715c83b5f qemu: Fix retrieval of maximum number of vCPUs on KVM hosts
The detection of the maximum number of cpus used incorrect ioctl
argument value. This flaw caused that on kvm hosts this returns always
"160" as the maximum. This is just a recommended maximum value. The real
value is higher than that.

This patch tweaks the detection function to behave as described by the
kernel docs:

https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Documentation/virtual/kvm/api.txt?id=refs/tags/v3.9-rc2#n199
2013-03-11 18:01:55 +01:00
Hu Tao
5c86ace1e7 nodeinfo: don't define nodeGetCellMemory if it isn't ever used
Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
2013-03-11 09:55:37 -06:00
Guido Günther
531b4fe8d0 Convert HAVE_SELINUX to WITH_SELINUX
these were missed by 63f18f3786
2013-03-11 11:42:21 +01:00
Guido Günther
6082bc27d0 lxc: Init activeUsbHostdevs
otherwise we crash with

 #0  virUSBDeviceListFind (list=0x0, dev=dev@entry=0x8193d70) at util/virusb.c:526
 #1  0xb1a4995b in virLXCPrepareHostdevUSBDevices (driver=driver@entry=0x815d9a0, name=0x815dbf8 "debian-700267", list=list@entry=0x81d8f08) at lxc/lxc_hostdev.c:88
 #2  0xb1a49fce in virLXCPrepareHostUSBDevices (def=0x8193af8, driver=0x815d9a0) at lxc/lxc_hostdev.c:261
 #3  virLXCPrepareHostDevices (driver=driver@entry=0x815d9a0, def=0x8193af8) at lxc/lxc_hostdev.c:328
 #4  0xb1a4c5b1 in virLXCProcessStart (conn=0x817d3f8, driver=driver@entry=0x815d9a0, vm=vm@entry=0x8190908, autoDestroy=autoDestroy@entry=false, reason=reason@entry=VIR_DOMAIN_RUNNING_BOOTED)
     at lxc/lxc_process.c:1068
 #5  0xb1a57e00 in lxcDomainStartWithFlags (dom=dom@entry=0x815e460, flags=flags@entry=0) at lxc/lxc_driver.c:1014
 #6  0xb1a57fc3 in lxcDomainStart (dom=0x815e460) at lxc/lxc_driver.c:1046
 #7  0xb79c8375 in virDomainCreate (domain=domain@entry=0x815e460) at libvirt.c:8450
 #8  0x08078959 in remoteDispatchDomainCreate (args=0x81920a0, rerr=0xb65c21d0, client=0xb0d00490, server=<optimized out>, msg=<optimized out>) at remote_dispatch.h:1066
 #9  remoteDispatchDomainCreateHelper (server=0x80c4928, client=0xb0d00490, msg=0xb0d005b0, rerr=0xb65c21d0, args=0x81920a0, ret=0x815d208) at remote_dispatch.h:1044
 #10 0xb7a36901 in virNetServerProgramDispatchCall (msg=0xb0d005b0, client=0xb0d00490, server=0x80c4928, prog=0x80c6438) at rpc/virnetserverprogram.c:432
 #11 virNetServerProgramDispatch (prog=0x80c6438, server=server@entry=0x80c4928, client=0xb0d00490, msg=0xb0d005b0) at rpc/virnetserverprogram.c:305
 #12 0xb7a300a7 in virNetServerProcessMsg (msg=<optimized out>, prog=<optimized out>, client=<optimized out>, srv=0x80c4928) at rpc/virnetserver.c:162
 #13 virNetServerHandleJob (jobOpaque=0xb0d00510, opaque=0x80c4928) at rpc/virnetserver.c:183
 #14 0xb7924f98 in virThreadPoolWorker (opaque=opaque@entry=0x80a94b0) at util/virthreadpool.c:144
 #15 0xb7924515 in virThreadHelper (data=0x80a9440) at util/virthreadpthread.c:161
 #16 0xb7887c39 in start_thread (arg=0xb65c2b70) at pthread_create.c:304
 #17 0xb77eb78e in clone () at ../sysdeps/unix/sysv/linux/i386/clone.S:130

when adding a domain with a usb device. This is Debian bug

    http://bugs.debian.org/700267
2013-03-11 11:41:58 +01:00
Michal Privoznik
f3fb916de9 bandwidth: Require network QoS if interface uses 'floor'
By current implementation, network inbound is required in order
to use 'floor' for guaranteeing  minimal throughput. This is so,
because we want user to tell us the maximal throughput of the
network instead of finding out ourselves (and detect bogus values
in case of virtual interfaces). However, we are nowadays
requiring this only on documentation level. So if user starts a
domain with 'floor' set on one its interfaces, we silently ignore
the setting. We should error out instead.
2013-03-11 10:51:32 +01:00
Dusty Mabe
d3092c60f7 capabilities: add NUMA memory information
'virsh capabilities' will now include a new <memory> element
per <cell> of the topology, as in:

    <topology>
      <cells num='2'>
        <cell id='0'>
          <memory unit='KiB'>12572412</memory>
          <cpus num='12'>
          ...
        </cell>

Signed-off-by: Eric Blake <eblake@redhat.com>
2013-03-08 11:51:00 -07:00
Guido Günther
c8871d8fbd lxc: include sys/stat.h
This fixes the build on Debian Wheezy which otherwise fails with:

  CC     libvirt_driver_lxc_impl_la-lxc_process.lo
  lxc/lxc_process.c: In function 'virLXCProcessGetNsInode':
  lxc/lxc_process.c:648:5: error: implicit declaration of function 'stat' [-Werror=implicit-function-declaration]
  lxc/lxc_process.c:648:5: error: nested extern declaration of 'stat' [-Werror=nested-externs]
  cc1: all warnings being treated as errors
2013-03-08 19:11:32 +01:00
Michal Privoznik
5a791c8995 qemuDomainBlockStatsFlags: Guard disk lookup with a domain job
When there are two concurrent threads, we may dereference a NULL
pointer, even though it has been checked before:

1. Thread1: starts executing qemuDomainBlockStatsFlags() with nparams != 0.
            It finds given disk and successfully pass check for disk->info.alias
            not being NULL.
2. Thread2: starts executing qemuDomainDetachDeviceFlags() on the very same
            disk as Thread1 is working on.
3. Thread1: gets to qemuDomainObjBeginJob() where it sets a job on a
            domain.
4. Thread2: also tries to set a job. However, we are not guaranteed which
            thread wins. So assume it's Thread2 who can continue.
5. Thread2: does the actual detach and frees disk->info.alias
6. Thread2: quits the job
7. Thread1: now successfully acquires the job, and accesses a NULL pointer.
2013-03-08 13:09:32 +01:00
Guannan Ren
ce4557c3ab apparmor: use AppArmorSetFDLabel for both imageFD and tapFD
Rename AppArmorSetImageFDLabel to AppArmorSetFDLabel which could
be used as a common function for *ALL* fd relabelling in Linux.

In apparmor profile for specific vm with uuid cdbebdfa-1d6d-65c3-be0f-fd74b978a773
Path: /etc/apparmor.d/libvirt/libvirt-cdbebdfa-1d6d-65c3-be0f-fd74b978a773.files
The last line is for the tapfd relabelling.

 # DO NOT EDIT THIS FILE DIRECTLY. IT IS MANAGED BY LIBVIRT.
  "/var/log/libvirt/**/rhel6qcow2.log" w,
  "/var/lib/libvirt/**/rhel6qcow2.monitor" rw,
  "/var/run/libvirt/**/rhel6qcow2.pid" rwk,
  "/run/libvirt/**/rhel6qcow2.pid" rwk,
  "/var/run/libvirt/**/*.tunnelmigrate.dest.rhel6qcow2" rw,
  "/run/libvirt/**/*.tunnelmigrate.dest.rhel6qcow2" rw,
  "/var/lib/libvirt/images/rhel6u3qcow2.img" rw,
  "/dev/tap45" rw,
2013-03-08 10:56:07 +08:00
Daniel P. Berrange
ab1ef3bc6c Include pid namespace inode in LXC audit messages
To allow the efficient correlation of container audit messages
with host hosts, include the pid namespace inode in audit
messages.
2013-03-07 19:43:53 +00:00
Daniel P. Berrange
eaf7d4ddff Add support for disks backed by plain files in LXC
By using a loopback device, disks backed by plain files can
be made available to LXC containers. We make no attempt to
auto-detect format if <driver type="raw"/> is not set,
instead we unconditionally treat that as meaning raw. This
is to avoid the security issues inherent with format
auto-detection

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-03-07 18:56:52 +00:00
Daniel P. Berrange
f0bfb6302d Refactor loop device setup code in LXC
Minor re-factoring of code for setting up loop devices in
the LXC controller

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-03-07 18:56:52 +00:00
Daniel P. Berrange
82793a2a55 Convert QEMU driver to use virLogProbablyLogMessage
The current QEMU code for skipping log messages only skips over
'debug' message, switch to virLogProbablyLogMessage to make sure
it skips over all of them
2013-03-07 18:56:52 +00:00
Daniel P. Berrange
09f5e0123f Improve LXC startup error reporting
Currently we rely on a VIR_ERROR message being logged by the
virRaiseError function to report LXC startup errors. This gives
the right message, but is rather ugly and can be truncated
if lots of log messages are written. Change the LXC controller
to explicitly print any virErrorPtr message to stderr. Then
change the driver to skip over anything that looks like a log
message.

The result is that this

error: Failed to start domain busy
error: internal error guest failed to start: 2013-03-04 19:46:42.846+0000: 1734: info : libvirt version: 1.0.2
2013-03-04 19:46:42.846+0000: 1734: error : virFileLoopDeviceAssociate:600 : Unable to open /root/disk.raw: No such file or directory

changes to

error: Failed to start domain busy
error: internal error guest failed to start: Unable to open /root/disk.raw: No such file or directory
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-03-07 18:56:52 +00:00
Daniel P. Berrange
f3d312f6c8 Add method for checking if a string is (probably) a log message
When reading log output from QEMU/LXC we need to skip over any
libvirt log messages. Currently the QEMU driver checks for a
fixed string, but this is better done with a regex. Add a method
virLogProbablyLogMessage to do a regex check

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-03-07 18:56:52 +00:00
Daniel P. Berrange
58e0accd8a Use VIR_MASS_CLOSE in LXC container startup
In the LXC container startup code when switching stdio
streams, we call VIR_FORCE_CLOSE on all FDs. This triggers
a huge number of warnings, but we don't see them because
stdio is closed at this point. strace() however shows them
which can confuse people debugging the code. Switch to
VIR_MASS_CLOSE to avoid this

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-03-07 18:10:36 +00:00
Daniel P. Berrange
495e3b2b50 Fix conditional build of virNetDevSetupControlFull
The virNetDevSetupControlFull function was protected by a
conditional on SIOCBRADDBR, which is bogus since it does
not use that symbol. Update the conditionals around all
callers to do stricter checks to ensure we always build
succesfully

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-03-07 18:08:33 +00:00
Daniel P. Berrange
3ed2e54500 Ensure GET_VLAN_VID_CMD is always defined
The RHEL4 vintage header files do not define GET_VLAN_VID_CMD.
Conditionally define it in our source, since the kernel can
raise a runtime error if it isn't supported

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-03-07 18:08:31 +00:00
Daniel P. Berrange
564e7d38a2 Don't import loop.h unless HAVE_DECL_LO_FLAGS_AUTOCLEAR is defined
The loop.h on RHEL4 is broken and cannot be imported. We already
detect this in configure as a side-effect of looking for whether
LO_FLAGS_AUTOCLEAR is available. We protected the impl with
HAVE_DECL_LO_FLAGS_AUTOCLEAR, but not the header import

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-03-07 18:07:27 +00:00
Daniel P. Berrange
c25426dc40 Rename 'daemon' param to 'binary' in virNetClientNewUNIX
To avoid a clash with daemon() libc API, rename the
'daemon' param in the header file to 'binary'. The
source file already uses the name 'binary'.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-03-07 18:06:59 +00:00
Daniel P. Berrange
74c47d091f Rename 'clone' to 'clonevol' to avoid name clash with clone() syscall
On RHEL-4 vintage one of the header files is polluted causing a
clash between the clone() syscall and the 'clone' parameter in
a libvirt driver API

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-03-07 18:06:11 +00:00
Eric Blake
2e6322a7a5 viralloc: use consistent naming
Commit 0df3e89 only touched the header, but the .c file had the
same shadowing potential.

* src/util/viralloc.c (virDeleteElementsN): s/remove/toremove/ to
match the header.
2013-03-07 07:53:42 -07:00
Eric Blake
0df3e8966c build: avoid shadowing a function name
Make the same fix as in commit de53eff.

* src/util/viralloc.h (virDeleteElementsN): Cater to old glibc.
2013-03-07 06:45:38 -07:00
Daniel P. Berrange
75e656a363 Fix crash parsing RNG device specification
Code that validates the whitelist for the RNG device filename
didn't account for fact that filename may be NULL. This led
to a NULL reference crash. This wasn't caught since the test
suite was not covering this XML syntax

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-03-07 12:57:10 +00:00
John Ferlan
1cf4ef1fca Resolve valgrind error
Resolves the following valgrind error from qemuxml2argvtest:

==20393== 5 bytes in 1 blocks are definitely lost in loss record 2 of 60
==20393==    at 0x4A0883C: malloc (vg_replace_malloc.c:270)
==20393==    by 0x38D690A167: __vasprintf_chk (in /usr/lib64/libc-2.16.so)
==20393==    by 0x4CB0D97: virVasprintf (stdio2.h:210)
==20393==    by 0x4CB0E53: virAsprintf (virutil.c:2017)
==20393==    by 0x428DC5: qemuAssignDeviceAliases (qemu_command.c:791)
==20393==    by 0x41DF93: testCompareXMLToArgvHelper (qemuxml2argvtest.c:151)
==20393==    by 0x41F53F: virtTestRun (testutils.c:157)
==20393==    by 0x41DA9B: mymain (qemuxml2argvtest.c:885)
==20393==    by 0x41FB7A: virtTestMain (testutils.c:719)
==20393==    by 0x38D6821A04: (below main) (in /usr/lib64/libc-2.16.so)
==20393==

From qemu_command.c/line 791:

    if (def->rng) {
        if (virAsprintf(&def->rng->info.alias, "rng%d", 0) < 0)
            goto no_memory;
    }
2013-03-06 16:03:50 -05:00
Jiri Denemark
4b0cb4a745 storage: Cleanup logical volume creation code
This patch plugs two memory leaks, removes some useless and confusing
constructs and renames renames "cleanup" label as "error" since it is
only used for error path rather then being common for both success and
error paths.
2013-03-06 14:53:00 +01:00
John Ferlan
80e524de86 sheepdog: Adjust logic to break while loop to avoid Coverity error
Change the various "return -1" to "break".  Avoids Coverity error and
perhaps other/future analyzer issues.
2013-03-05 22:52:51 -05:00
John Ferlan
40e904490f libxl_driver: Resolve Coverity errors
1. The virObjectLock() call was unconditional, but Unlock was conditional
   on vm being valid.  Removed the check

2. A call to virDomainEventNewFromObj() isn't guaranteed to return an
   event - that check needs to be made prior to libxlDomainEventQueue()
   of the event. Did not add libxlDriverLock/Unlock around the call since
   some callers already have lock taken

3. Need to initialize fd = -1 in libxlDoDomainSave() since we can jump
   to cleanup before it's set.

4. Missing break;'s in libxlDomainModifyDeviceFlags() for case
   LIBXL_DEVICE_UPDATE.  The default: case would report an error
2013-03-05 22:52:51 -05:00
John Ferlan
50de0e0807 libxl_conf: Resolve Coverity issue with call to regcomp() 2013-03-05 22:52:51 -05:00
Guannan Ren
0047d5d6e8 qemu: update domain live xml for virsh memtune with --live flag
virsh subcommand memtune forgot updating domain live xml
after setting cgroup value.
2013-03-06 11:46:33 +08:00
Guannan Ren
b38a040a29 util: fix a integer boundary error
A value which is equal to a integer maximum such as LLONG_MAX is
a valid integer value.

The patch fix the following error:
1, virsh memtune vm --swap-hard-limit -1
2, virsh start vm
In debug mode, it shows error like:
virScaleInteger:1813 : numerical overflow:\
                       value too large: 9007199254740991KiB
2013-03-06 11:46:33 +08:00
Peter Krempa
7fc4864a3a conf: Report errors on cputune parameter parsing
This patch adds proper error reporting if parsing of cputune parameters
fails due to incorrect values provided by the user. Previously no errors
were reported in such a case and the failure was silently ignored.
2013-03-05 08:35:28 +01:00
Peter Krempa
5d9169e4dc conf: Make virDomainDeviceInfoIterate usable without os type
Make the iterator function usable in the next patches. Also refactor
some parts to avoid strcmp if not necessary.

This commit tweaks and shadows the change that was done in commit
babe7dada0 and was needed after the
support for multiple console devices was added. Historically the first
<console> element is alias for the <serial> device.
2013-03-05 08:34:49 +01:00
Peter Krempa
bb98ba5d8f conf: whitespace cleanups and refactors with no semantic impact
This patch changes many unrelated places to simplify the code or update
code style. This patch should not have any semantic impact on the code.
2013-03-05 08:34:49 +01:00
Eric Blake
4932ef4502 rng: restrict passthrough names to known-good files
There is some controversy[1] on the qemu list on whether qemu should
have ever allowed arbitrary file name passthrough, or whether it
should be restricted to JUST /dev/random and /dev/hwrng.  It is
always easier to add support for additional filenames than it is
to remove support for something once released, so this patch
restricts libvirt 1.0.3 (where the virtio-random backend was first
supported) to just the two uncontroversial names, letting us defer
to a later date any decision on whether supporting arbitrary files
makes sense. Additionally, since qemu 1.4 does NOT support
/dev/fdset/nnn fd passthrough for the backend, limiting to just
two known names means that we don't get tempted to try fd
passthrough where it won't work.

[1]https://lists.gnu.org/archive/html/qemu-devel/2013-03/threads.html#00023

* src/conf/domain_conf.c (virDomainRNGDefParseXML): Only allow
/dev/random and /dev/hwrng.
* docs/schemas/domaincommon.rng: Flag invalid files.
* docs/formatdomain.html.in (elementsRng): Document this.
* tests/qemuxml2argvdata/qemuxml2argv-virtio-rng-random.args:
Update test to match.
* tests/qemuxml2argvdata/qemuxml2argv-virtio-rng-random.xml:
Likewise.
2013-03-04 17:45:38 -07:00
John Ferlan
f7e7429416 libvirt: Update headers for doc
Update the function prototypes to include a message about the client needing
to free() returned name fields.  Fix the all domains example flags values.
2013-03-04 17:36:03 -05:00
Satoru Moriya
464ad16f5c qemu: fix wrong evaluation in qemuDomainSetMemoryParameters
19c6ad9a (qemu: Refactor qemuDomainSetMemoryParameters) introduced
a new macro, VIR_GET_LIMIT_PARAMETER(PARAM, VALUE). But if statement
in the macro is not correct and so set_XXXX flags are set to false
in the wrong. As a result, libvirt ignores all memtune parameters.
This patch fixes the conditional expression to work correctly.

Signed-off-by: Satoru Moriya <satoru.moriya@hds.com>
2013-03-04 18:34:28 +01:00
Guannan Ren
b95c13cd33 util: use string libvirt to prefix error message instead of libvir
BZ:https://bugzilla.redhat.com/show_bug.cgi?id=912021
Without error handler set, virDefaultErrorFunc will be called, the
error message is prefixed with "libvir:". It become a little better
by using prefix "libvirt:" when working with upper application.

For example:
1, stop libvirtd daemon
2, run virt-top.
libvir: XML-RPC error : Failed to connect \
        socket to '/var/run/libvirt/libvirt-sock-ro': \
        No such file or directory
libvirt: VIR_ERR_SYSTEM_ERROR: VIR_FROM_RPC: \
        Failed to connect socket to '/var/run/libvirt/libvirt-sock-ro': \
        No such file or directory
2013-03-04 23:21:20 +08:00
Peter Krempa
9933a6b2fa qemu: Remove managed save flag from VM when starting with --force-boot
At the start of the guest after the image is unlinked the state wasn't
touched up to match the state on disk.
2013-03-04 12:10:28 +01:00
Christophe Fergeau
aff6942c23 qemu: Use -1 as unpriviledged uid/gid
Commit f506a4c1 changed virSetUIDGID() to be a noop
when uid/gid are -1, while it used to be a noop when
they are <= 0.

The changes in this commit broke creating new VMs in GNOME Boxes
as qemuDomainCheckDiskPresence gets called during domain creation/startup,
which in turn calls virFileAccessibleAs which fails after calling
virSetUIDGID(0, 0) (Boxes uses session libvirtd). virSetUIDGID is called with
(0, 0) as these are the default user/group values in virQEMUDriverConfig
for session libvirtd.

This commit changes virQEMUDriverConfigNew to use -1 as the unpriviledged
uid/gid. I've also looked at the various places where cfg->user is used,
and they all seem to handle -1 correctly.
2013-03-04 08:50:09 +01:00
Michal Privoznik
1cf97c87c0 virnetdevmacvlan.c: Introduce mutex for macvlan creation
Currently, after we removed the qemu driver lock, it may happen
that two or more threads will start up a machine with macvlan and
race over virNetDevMacVLanCreateWithVPortProfile(). However,
there's a racy section in which we are generating a sequence of
possible device names and detecting if they exits. If we found
one which doesn't we try to create a device with that name.
However, the other thread is doing just the same. Assume it will
succeed and we must therefore fail. If this happens more than 5
times (which in massive parallel startup surely will) we return
-1 without any error reported. This patch is a simple hack to
both of these problems. It introduces a mutex, so only one thread
will enter the section, and if it runs out of possibilities,
error is reported. Moreover, the number of retries is raised to 20.
2013-03-01 11:33:29 +01:00
Daniel P. Berrange
9c4ecb3e8e Revert hack for autodestroy in qemuProcessStop
This reverts the hack done in

commit 568a6cda27
Author: Jiri Denemark <jdenemar@redhat.com>
Date:   Fri Feb 15 15:11:47 2013 +0100

    qemu: Avoid deadlock in autodestroy

since we now have a fix which avoids the deadlock scenario
entirely
2013-03-01 10:18:27 +00:00
Daniel P. Berrange
96b893f092 Fix deadlock in QEMU close callback APIs
There is a lock ordering problem in the QEMU close callback
APIs.

When starting a guest we have a lock on the VM. We then
set a autodestroy callback, which acquires a lock on the
close callbacks.

When running auto-destroy, we obtain a lock on the close
callbacks, then run each callbacks - which obtains a lock
on the VM.

This causes deadlock if anyone tries to start a VM, while
autodestroy is taking place.

The fix is to do autodestroy in 2 phases. First obtain
all the callbacks and remove them from the list under
the close callback lock. Then invoke each callback
from outside the close callback lock.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-03-01 10:16:29 +00:00
Daniel P. Berrange
7ccad0b16d Fix crash in QEMU auto-destroy with transient guests
When the auto-destroy callback runs it is supposed to return
NULL if the virDomainObjPtr is no longer valid. It was not
doing this for transient guests, so we tried to virObjectUnlock
a mutex which had been freed. This often led to a crash.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-03-01 10:16:29 +00:00