Commit Graph

1219 Commits

Author SHA1 Message Date
Michal Privoznik
2a1ae8fba7 lib: Preserve error around virDomainNetReleaseActualDevice()
This function is calling public API virNetworkLookupByName()
which resets the error. Therefore, if
virDomainNetReleaseActualDevice() is used in cleanup path it
actually resets the original error that got us jump into
'cleanup' label.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2019-04-30 17:00:46 +02:00
Daniel P. Berrangé
e007e8ba3a Revert "virt drivers: don't handle type=network after resolving actual network type"
This reverts commit 2f5e6502e3.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-04-30 14:42:22 +01:00
Michal Privoznik
08193fdbf5 src: Check for virDomainDiskInsert() retval properly
Our coding style specifies that only negative values are considered as
error. Check for return value of virDomainDiskInsert() properly,
following the style. Not that the function can now return anything other
than 0 or -1, but it just triggers my OCD.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2019-04-26 15:14:17 +02:00
Daniel P. Berrangé
2f5e6502e3 virt drivers: don't handle type=network after resolving actual network type
The call to resolve the actual network type will turn any NICs with
type=network into one of the other types. Thus there should be no need
to handle type=network in later switch() statements jumping off the
actual type.

Reviewed-by: Cole Robinson <crobinso@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-04-18 13:10:06 +01:00
Daniel P. Berrangé
e1d10f8ef2 network: pass a virNetworkPtr to port management APIs
The APIs for allocating/notifying/removing network ports just take
an internal domain interface struct right now. As a step towards
turning these into public facing APIs, add a virNetworkPtr argument
to all of them.

Reviewed-by: Cole Robinson <crobinso@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-04-16 14:44:53 +01:00
Daniel P. Berrangé
dd52444f23 network: restrict usage of port management APIs
The port allocation APIs are currently called unconditionally for all
types of NIC, but (mostly) only do anything for NICs with type=network.

The exception is the port allocate API which does some validation even
for NICs with type!=network. Relying on this validation is flawed,
however, since the network driver may not even be installed. IOW virt
drivers must not delegate validation to the network driver for NICs
with type != network.

This change allows us to report errors when the virtual network driver
is not registered.

Reviewed-by: Cole Robinson <crobinso@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-04-16 14:44:53 +01:00
Andrea Bolognani
03a07357e1 maint: Add filetype annotations to Makefile.inc.am
Vim has trouble figuring out the filetype automatically because
the name doesn't follow existing conventions; annotations like
the ones we already have in Makefile.ci help it out.

Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2019-04-12 16:55:38 +02:00
Cole Robinson
1d31526b52 Always put _LAST enums on second line of VIR_ENUM_IMPL
Standardize on putting the _LAST enum value on the second line
of VIR_ENUM_IMPL invocations. Later patches that add string labels
to VIR_ENUM_IMPL will push most of these to the second line anyways,
so this saves some noise.

Signed-off-by: Cole Robinson <crobinso@redhat.com>
2019-04-11 12:47:23 -04:00
Peter Krempa
f785318187 Revert "Include unistd.h directly by files using it"
This reverts commit a5e1602090.

Getting rid of unistd.h from our headers will require more work than
just fixing the broken mingw build. Revert it until I have a more
complete proposal.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
2019-04-10 12:26:32 +02:00
Peter Krempa
a5e1602090 Include unistd.h directly by files using it
util/virutil.h bogously included unistd.h. Drop it and replace it by
including it directly where needed.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-04-10 09:12:04 +02:00
Peter Krempa
285c5f28c4 util: Move enum convertors into virenum.(c|h)
virutil.(c|h) is a very gross collection of random code. Remove the enum
handlers from there so we can limit the scope where virtutil.h is used.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-04-10 09:12:04 +02:00
Peter Krempa
c0abcca417 util: Don't include 'viralloc.h' into other header files
'viralloc.h' does not provide any type or macro which would be necessary
in headers. Prevent leakage of the inclusion.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-04-10 09:12:04 +02:00
Cole Robinson
c53acd2ad1 Drop needless virtType validation
This code originates from:

commit d0aa10fdd6
Author: Daniel P. Berrange <berrange@redhat.com>
Date:   Tue Mar 3 12:03:44 2009 +0000

    QEMU security driver usage for sVirt support (James Morris, Dan Walsh, Daniel Berrange)

Originally in the qemudDomainGetSecurityLabel function. It doesn't
appear to have done anything useful back then either. The other two
instances look like copy+paste

Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Cole Robinson <crobinso@redhat.com>
2019-03-18 09:35:00 -04:00
Andrea Bolognani
c0a4a98eab Fix names for abs_top_{src,build}dir variables
According to the official documentation for autoconf[1], the
correct names for these variables are abs_top_{src,build}dir
rather than abs_top{src,build}dir; in fact, we're already
using the correct names in various places, so let's just make
everything nice and consistent.

[1] https://www.gnu.org/software/autoconf/manual/autoconf-2.69/html_node/Preset-Output-Variables.html

Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
2019-03-14 10:05:28 +01:00
Maxim Kozin
14b6a1854f lxc: Try harder to stop/reboot containers
If shutting down a container via setting the runlevel fails, the
control jumps right onto endjob label and doesn't even try
sending the signal. If flags allow it, we should try both
methods.

Signed-off-by: Maxim Kozin <kolomaxes@gmail.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2019-03-07 18:02:51 +01:00
Michal Privoznik
fc380c2e01 Revert "virStateDriver - Separate AutoStart from Initialize"
https://bugzilla.redhat.com/show_bug.cgi?id=1685151

This reverts commit cefb97fb81.

The stateAutoStart callback will be removed in the next commit.
Therefore move autostarting of domains, networks and storage
pools back into stateInitialize callbacks.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-03-06 10:20:31 +01:00
Peter Krempa
bd734bbbce util: string: Use VIR_AUTOSTRINGLIST instead of VIR_AUTOPTR(virString)
Use of VIR_AUTOPTR and virString is confusing as it's a list and not a
single pointer. Replace it by VIR_AUTOSTRINGLIST as string lists are
basically the only sane NULL-terminated list we can have.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2019-03-04 13:04:20 +01:00
Julio Faracco
ac62e297db lxc: Converting 'if, else' logic into a 'switch, case'
The structure used to handle network entries was based on 'if,else'
conditions. This commit converts this ugly structure into a switch to
clearify each option of the handler.

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-02-25 10:41:39 -05:00
Julio Faracco
087a7c9a88 lxc: Introduce lxcNetworkParseDataType
Extract out the network "type" processing into it's own method
rather than inline within lxcNetworkParseDataSuffix.

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-02-25 10:41:39 -05:00
Julio Faracco
f7fd10e5f8 lxc: Introduce lxcNetworkParseDataSuffix
This commit removes the full network entry setting: "lxc.network.X" to
type only. Like "type", "name", "flags", etc. This will handle entries
regardless of whether they are prefixed by "lxc.network." (today) or
"lxc.net.X." (the future).

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-02-25 10:41:39 -05:00
Julio Faracco
0ebb057a2a lxc: Introduce lxcNetworkParseDataEntry
Refactor lxcNetworkWalkCallback to be a simple method to handle
both possible network settings with indexes or the simple one. It is
better the decouple the whole algorithm to parse data to only parse
which entry type libvirt is handling.

The new method is responsible to verify is the settings correspond to
network entry. Right now, it is only verifying "lxc.network.", but in
the future, it can be used to verify "lxc.net.X." too. Any other case
would be rejected.

On the other hand, the idea here is working only with types. If we know
that entry is part of network settings, after we just need to know which
type is. It keeps the handler simple.

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-02-25 10:41:39 -05:00
Julio Faracco
e6cb63d2ef lxc: Create a separate method to handle IPv{4, 6} outside parser
The new method called lxcNetworkParseDataIPs() is responsible to handle
IPv{4,6} settings now. The idea is let lxcNetworkWalkCallback() method
handle all entries related to network definition only.

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-02-25 10:41:39 -05:00
Eric Blake
27c8fd7490 domain: Fix unknown flags diagnosis in virDomainGetXMLDesc
Many drivers had a comment that they did not validate the incoming
'flags' to virDomainGetXMLDesc() because they were relying on
virDomainDefFormat() to do it instead. This used to be the case
(at least since 461e0f1a and friends in 0.9.4 added unknown flag
checking in general), but regressed in commit 0ecd6851 (1.2.12),
when all of the drivers were changed to pass 'flags' through the
new helper virDomainDefFormatConvertXMLFlags(). Since this helper
silently ignores unknown flags, we need to implement flag checking
in each driver instead.

Annoyingly, this means that any new flag values added will silently
be ignored when targeting an older libvirt, rather than our usual
practice of loudly diagnosing an unsupported flag.  Add comments
in domain_conf.[ch] to remind us to be extra vigilant about the
impact when adding flags (a new flag to add data is safe if the
older server omitting the requested data doesn't break things in
the newer client; a new flag to suppress data rather than enhancing
the existing VIR_DOMAIN_XML_SECURE may form a data leak or even a
security hole).

In the qemu driver, there are multiple callers all funnelling to
qemuDomainDefFormatBufInternal(); many of them already validated
flags (and often only a subset of the full set of possible flags),
but for ease of maintenance, we can also check flags at the common
helper function.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-02-19 16:52:51 -06:00
Ján Tomko
0f110d5ac8 Use NULLSTR_EMPTY
Instead of repetitive:
  s ? s : ""
use NULLSTR_EMPTY.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
2019-02-14 14:09:38 +01:00
Michal Privoznik
94fce25546 lxc: Don't reboot host on virDomainReboot
If the container is really a simple one (init is just bash and
the whole root is passed through) then virDomainReboot and
virDomainShutdown will talk to the actual init within the host.
Therefore, 'virsh shutdown $dom' will result in shutting down the
host. True, at that point the container is shut down too but
looks a bit harsh to me.

The solution is to check if the init inside the container is or
is not the same as the init running on the host.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2019-02-07 11:36:41 +01:00
Michal Privoznik
64eca3d5e3 virinitctl: Expose fifo paths and allow caller to chose one
So far the virInitctlSetRunLevel() is fully automatic. It finds
the correct fifo to use to talk to the init and it will set the
desired runlevel. Well, callers (so far there is just one) will
need to inspect the fifo a bit just before the runlevel is set.
Therefore, expose the internal list of fifos and also allow
caller to explicitly use one.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2019-02-07 11:24:09 +01:00
Michal Privoznik
16c123679c lxc: Restore seclabels after the container is killed
Due to a bug the seclabels are restored before any PID in the
container is killed. This should be done afterwards in
virLXCProcessCleanup.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2019-02-07 11:17:51 +01:00
Michal Privoznik
797bdb3ce8 lxc: Use correct job type for destroying a domain
Not that it would matter because LXC driver doesn't differentiate
the job types so far, but nevertheless the Destroy() should grab
LXC_JOB_DESTROY.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2019-02-07 11:13:56 +01:00
Cole Robinson
af36f8a641 Require a semicolon for VIR_ONCE_GLOBAL_INIT calls
Missing semicolon at the end of macros can confuse some analyzers
(like cppcheck <filename>). VIR_ONCE_GLOBAL_INIT is almost
exclusively called without an ending semicolon, but let's
standardize on using one like the other macros.

Add a dummy struct definition at the end of the macro, so
the compiler will require callers to add a semicolon.

Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Cole Robinson <crobinso@redhat.com>
2019-02-03 17:46:29 -05:00
Cole Robinson
6a4d938dd3 Require a semicolon for VIR_ENUM_IMPL calls
Missing semicolon at the end of macros can confuse some analyzers
(like cppcheck <filename>), and we have a mix of semicolon and
non-semicolon usage through the code. Let's standardize on using
a semicolon for VIR_ENUM_IMPL calls.

Move the verify() statement to the end of the macro and drop
the semicolon, so the compiler will require callers to add a
semicolon.

While we are touching these call sites, standardize on putting
the closing parenth on its own line, as discussed here:
https://www.redhat.com/archives/libvir-list/2019-January/msg00750.html

Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Cole Robinson <crobinso@redhat.com>
2019-02-03 17:46:29 -05:00
Cole Robinson
7662194bf3 Require a semicolon to VIR_ENUM_DECL calls
Missing semicolon at the end of macros can confuse some analyzers
(like cppcheck <filename>), and we have a mix of semicolon and
non-semicolon usage through the code. Let's standardize on using
a semicolon for VIR_ENUM_DECL calls.

Drop the semicolon from the final statement of the macro, so
the compiler will require callers to add a semicolon.

Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Cole Robinson <crobinso@redhat.com>
2019-02-03 17:46:29 -05:00
Peter Krempa
c938c35363 security: Remove disk labeling functions and fix callers
Now that we have replacement in the form of the image labeling function
we can drop the unnecessary functions by replacing all callers.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-30 17:20:38 +01:00
Daniel P. Berrangé
c10a6d50a4 lxc: allow empty path in URI for historical compatibility
The use of 'lxc://' was mistakenly broken in:

  commit 4c8574c85c
  Author: Daniel P. Berrangé <berrange@redhat.com>
  Date:   Wed Mar 28 12:49:29 2018 +0100

    driver: ensure NULL URI isn't passed to drivers with whitelisted URIs

Allow it again for historical compatibility.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-01-09 14:10:00 +00:00
Radostin Stoyanov
f8f525ff86 lxc: Set max uid/gid mappings for user namespace
There is a limit on the number of lines in the /proc/<pid>/{g,u}id_map
files. In Linux 4.14 and earlier, this limit was (arbitrarily) set at
5 lines. Since Linux 4.15, which was released on 28 Jan 2018, the limit
is 340 lines.

This change is documented in user_namespaces(7).

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6397fac4915ab3002dc15aae751455da1a852f25

Signed-off-by: Radostin Stoyanov <rstoyanov1@gmail.com>
2018-12-17 11:03:29 +00:00
Daniel P. Berrangé
568a417224 Enforce a standard header file guard symbol name
Require that all headers are guarded by a symbol named

  LIBVIRT_$FILENAME

where $FILENAME is the uppercased filename, with all characters
outside a-z changed into '_'.

Note we do not use a leading __ because that is technically a
namespace reserved for the toolchain.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-12-14 10:47:13 +00:00
Daniel P. Berrangé
4cfd709021 Fix many mistakes & inconsistencies in header file layout
This introduces a syntax-check script that validates header files use a
common layout:

  /*
   ...copyright header...
   */
  <one blank line>
  #ifndef SYMBOL
  # define SYMBOL
  ....content....
  #endif /* SYMBOL */

For any file ending priv.h, before the #ifndef, we will require a
guard to prevent bogus imports:

  #ifndef SYMBOL_ALLOW
  # error ....
  #endif /* SYMBOL_ALLOW */
  <one blank line>

The many mistakes this script identifies are then fixed.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-12-14 10:46:53 +00:00
Daniel P. Berrangé
600462834f Remove all Author(s): lines from source file headers
In many files there are header comments that contain an Author:
statement, supposedly reflecting who originally wrote the code.
In a large collaborative project like libvirt, any non-trivial
file will have been modified by a large number of different
contributors. IOW, the Author: comments are quickly out of date,
omitting people who have made significant contribitions.

In some places Author: lines have been added despite the person
merely being responsible for creating the file by moving existing
code out of another file. IOW, the Author: lines give an incorrect
record of authorship.

With this all in mind, the comments are useless as a means to identify
who to talk to about code in a particular file. Contributors will always
be better off using 'git log' and 'git blame' if they need to  find the
author of a particular bit of code.

This commit thus deletes all Author: comments from the source and adds
a rule to prevent them reappearing.

The Copyright headers are similarly misleading and inaccurate, however,
we cannot delete these as they have legal meaning, despite being largely
inaccurate. In addition only the copyright holder is permitted to change
their respective copyright statement.

Reviewed-by: Erik Skultety <eskultet@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-12-13 16:08:38 +00:00
Julio Faracco
53762677a8 lxc: Initializing IPv6 and IPv4 gateway to overwrite old settings.
This commit fixes a bug when you have multiple network settings defined.
Basically, if you set an IPv6 or IPv4 gateway, it carries on next
network settings. It is happening because the data is not being
initialized when a new network type is defined. So, the old data still
persists into the pointer. Another way to initialized the data was
introduced using memset() to avoid missing attributes from the struct.

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2018-12-11 15:02:56 -05:00
Laine Stump
c55ff370f8 lxc: don't forbid <interface type='direct'>
Commit 017dfa27d changed a few switch statements in the LXC code to
have all possible enum values, and in the process changed the switch
statement in virLXCControllerGetNICIndexes() to return an error status
for unsupported interface types, but it erroneously put type='direct'
on the list of unsupported types.

type='direct' (implemented with a macvlan interface) is supported on
LXC, but it's interface shouldn't be placed on the list of interfaces
given to CreateMachineWithNetwork() because the interface is put
inside the container, while CreateMachineWithNetwork() only wants to
know about the parent veths of veth pairs (the parent veth remains on
the host side, while the child veth is put into the container).

Resolves: https://bugzilla.redhat.com/1656463
Signed-off-by: Laine Stump <laine@laine.org>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2018-12-08 12:38:15 -05:00
Laine Stump
59603b62fa lxc: check actual type of interface not config type
virLXCControllerGetNICIndexes() was deciding whether or not to add the
ifindex for an interface's ifname to the list of ifindexes sent to
CreateMachineWithNetwork based on the interface type stored in the
config. This would be incorrect in the case of <interface
type='network'> where the network was giving out macvlan interfaces
tied to a physical device (i.e. when the actual interface type was
"direct").

Instead of checking the setting of "net->type", we should be checking
the setting of virDomainNetGetActualType(net).

I don't think this caused any actual misbehavior, it was just
technically wrong.

Signed-off-by: Laine Stump <laine@laine.org>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2018-12-08 12:37:32 -05:00
Yuri Chornoivan
e5c1fbca24 Fix minor typos in messages and docs
Signed-off-by: Yuri Chornoivan <yurchor@ukr.net>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
2018-12-05 10:39:54 +01:00
Michal Privoznik
0aad10cdae Revert "security_manager: Load lock plugin on init"
This reverts commit 3e26b476b5.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2018-11-16 13:42:39 +01:00
Julio Faracco
31b3584b2d lxc: Include support to lxc version 3.0 or higher.
This patch introduce the new settings for LXC 3.0 or higher. The older
versions keep the compatibility to deprecated settings for LXC, but
after release 3.0, the compatibility was removed. This commit adds the
support to the refactored settings.

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2018-11-14 15:00:18 -05:00
Julio Faracco
879fde3272 lxc: Clang is complaining about possible NULL pointer.
The array "mount" inside lxc_container is not being checked before for
loop. Clang syntax scan is complaining about this segmentation fault.

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2018-11-07 16:22:16 -05:00
John Ferlan
6830c81307 lxc: Only check @nparams in lxcDomainBlockStatsFlags
Remove the "!params" check from the condition since it's possible
someone could pass a non NULL value there, but a 0 for the nparams
and thus continue on.  The external API only checks if @nparams is
non-zero, then check for NULL @params.

Found by Coverity

Signed-off-by: John Ferlan <jferlan@redhat.com>
ACKed-by: Michal Privoznik <mprivozn@redhat.com>
2018-10-01 14:27:07 -04:00
Mark Asselstine
7882c6eca5 lxc_monitor: Avoid AB / BA lock race
A deadlock situation can occur when autostarting a LXC domain 'guest'
due to two threads attempting to take opposing locks while holding
opposing locks (AB BA problem). Thread A takes and holds the 'vm' lock
while attempting to take the 'client' lock, meanwhile, thread B takes
and holds the 'client' lock while attempting to take the 'vm' lock.

The potential for this can be seen as follows:

Thread A:
virLXCProcessAutostartDomain (takes vm lock)
 --> virLXCProcessStart
  --> virLXCProcessConnectMonitor
   --> virLXCMonitorNew
    --> virNetClientSetCloseCallback (wants client lock)

Thread B:
virNetClientIncomingEvent (takes client lock)
 --> virNetClientIOHandleInput
  --> virNetClientCallDispatch
   --> virNetClientCallDispatchMessage
    --> virNetClientProgramDispatch
     --> virLXCMonitorHandleEventInit
      --> virLXCProcessMonitorInitNotify (wants vm lock)

Since these threads are scheduled independently and are preemptible it
is possible for the deadlock scenario to occur where each thread locks
their first lock but both will fail to get their second lock and just
spin forever. You get something like:

virLXCProcessAutostartDomain (takes vm lock)
 --> virLXCProcessStart
  --> virLXCProcessConnectMonitor
   --> virLXCMonitorNew
<...>
virNetClientIncomingEvent (takes client lock)
 --> virNetClientIOHandleInput
  --> virNetClientCallDispatch
   --> virNetClientCallDispatchMessage
    --> virNetClientProgramDispatch
     --> virLXCMonitorHandleEventInit
      --> virLXCProcessMonitorInitNotify (wants vm lock but spins)
<...>
    --> virNetClientSetCloseCallback (wants client lock but spins)

Neither thread ever gets the lock it needs to be able to continue
while holding the lock that the other thread needs.

The actual window for preemption which can cause this deadlock is
rather small, between the calls to virNetClientProgramNew() and
execution of virNetClientSetCloseCallback(), both in
virLXCMonitorNew(). But it can be seen in real world use that this
small window is enough.

By moving the call to virNetClientSetCloseCallback() ahead of
virNetClientProgramNew() we can close any possible chance of the
deadlock taking place. There should be no other implications to the
move since the close callback (in the unlikely event was called) will
spin on the vm lock. The remaining work that takes place between the
old call location of virNetClientSetCloseCallback() and the new
location is unaffected by the move.

Signed-off-by: Mark Asselstine <mark.asselstine@windriver.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2018-09-25 17:08:08 +02:00
Pavel Hrdina
0772c34685 vircgroup: rename virCgroupAdd.*Task to virCgroupAdd.*Process
In cgroup v2 we need to handle processes and threads differently,
following patch will introduce virCgroupAddThread.

Reviewed-by: Fabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
2018-09-25 09:59:23 +02:00
John Ferlan
996f101431 lxc: Resolve memory leak
Commit 40b5c99a modified the virConfGetValue callers to use
virConfGetValueString. However, using the virConfGetValueString
resulted in leaking the returned @value string in each case.
So, let's modify each instance to use the VIR_AUTOFREE(char *)
syntax. In some instances changing the variable name since
@value was used more than once.

Found by Coverity

Signed-off-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2018-09-24 09:44:37 -04:00
John Ferlan
f6399b9d89 lxc: Remove unnecessary error label
Since lxcConvertSize already creates an error message, there
is no need to use an error: label in lxcSetMemTune to just
overwrite or essentially rewrite the same error. So remove
the label.

Signed-off-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2018-09-24 09:44:31 -04:00
Erik Skultety
5165ff0971 src: More cleanup of some system headers already contained in internal.h
All of the ones being removed are pulled in by internal.h. The only
exception is sanlock which expects the application to include <stdint.h>
before sanlock's headers, because sanlock prototypes use fixed width
int, but they don't include stdint.h themselves, so we have to leave
that one in place.

Signed-off-by: Erik Skultety <eskultet@redhat.com>
Acked-by: Michal Privoznik <mprivozn@redhat.com>
2018-09-20 10:16:39 +02:00