Cgroups are linux specific and we need to make sure that the code is
compiled only on linux.  On different OSes it fails the compilation:

../../src/util/vircgroupv1.c:65:19: error: variable has incomplete type 'struct mntent'
    struct mntent entry;
                  ^
../../src/util/vircgroupv1.c:65:12: note: forward declaration of 'struct mntent'
    struct mntent entry;
           ^
../../src/util/vircgroupv1.c:74:12: error: implicit declaration of function 'getmntent_r' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
    while (getmntent_r(mounts, &entry, buf, sizeof(buf)) != NULL) {
           ^
../../src/util/vircgroupv1.c:814:39: error: use of undeclared identifier 'MS_NOSUID'
    if (mount("tmpfs", root, "tmpfs", MS_NOSUID|MS_NODEV|MS_NOEXEC, opts) < 0) {
                                      ^
../../src/util/vircgroupv1.c:814:49: error: use of undeclared identifier 'MS_NODEV'
    if (mount("tmpfs", root, "tmpfs", MS_NOSUID|MS_NODEV|MS_NOEXEC, opts) < 0) {
                                                ^
../../src/util/vircgroupv1.c:814:58: error: use of undeclared identifier 'MS_NOEXEC'
    if (mount("tmpfs", root, "tmpfs", MS_NOSUID|MS_NODEV|MS_NOEXEC, opts) < 0) {
                                                         ^
../../src/util/vircgroupv1.c:841:65: error: use of undeclared identifier 'MS_BIND'
            if (mount(src, group->legacy[i].mountPoint, "none", MS_BIND,
                                                                ^
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

All the system headers are used only if we are compiling on linux
and they all are present otherwise we would have seen build errors
because in our tests/vircgrouptest.c we use only __linux__ to check
whether to skip the cgroup tests or not.
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

tests/vircgrouptest.c uses #ifdef __linux__ for a long time and no
failure was reported so far so it's safe to assume that __linux__ is
good enough to guard cgroup code.
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

The domxml-to-native virsh command accepts either --xml or --domain
option followed by a file or domain name respectively. The --domain
option is documented as required, which means an argument with no option
is treated as --xml. Commit v4.3.0-127-gd86531da broke this by making
--domain optional and thus an argument with no option was treated as
--domain.

https://bugzilla.redhat.com/show_bug.cgi?id=1633077Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

Commit 95d19cd0 unconditionally adjusted the tests to account for
the conditional move of the nested_hvm setting location.

Run the affected tests only for the new setup (witnessed by
LIBXL_HAVE_BUILDINFO_NESTED_HVM).
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NErik Skultety <eskultet@redhat.com>

Let's ignore the checking of interface type when we call the function
qemuARPGetInterfaces to get IP from host's arp table.
Signed-off-by: NLin Ma <lma@suse.com>
Reviewed-by: NChen Hanxiao <chenhanxiao@gmail.com>

It may happen that in the list of paths/disk sources to relabel
there is a disk source. If that is the case, the path is NULL. In
that case, we shouldn't try to lock the path. It's likely a
network disk anyway and therefore there is nothing to lock.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NErik Skultety <eskultet@redhat.com>

This shouldn't be needed per-se. Security manager shouldn't
disappear during transactions - it's immutable. However, it
doesn't hurt to grab a reference either - transaction code uses
it after all.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NMarc Hartmayer <mhartmay@linux.ibm.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

This array is allocated in virSecuritySELinuxContextListAppend()
but never freed. This commit is essentially the same as ca250269.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

Use the mnemonic macros of libdbus for 1 (TRUE) and 0 (FALSE).
Signed-off-by: NMarc Hartmayer <mhartmay@linux.ibm.com>
Reviewed-by: NBjoern Walk <bwalk@linux.ibm.com>
Reviewed-by: NBoris Fiuczynski <fiuczy@linux.ibm.com>
Reviewed-by: NStefan Zimmermann <stzi@linux.ibm.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

Report a debug message if dbus_watch_handle() returns FALSE.
dbus_watch_handle() returns FALSE if there wasn't enough memory for
reading or writing.
Signed-off-by: NMarc Hartmayer <mhartmay@linux.ibm.com>
Reviewed-by: NBjoern Walk <bwalk@linux.ibm.com>
Reviewed-by: NBoris Fiuczynski <fiuczy@linux.ibm.com>
Reviewed-by: NStefan Zimmermann <stzi@linux.ibm.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

As documented at
https://dbus.freedesktop.org/doc/api/html/group__DBusConnection.html#ga2522ac5075dfe0a1535471f6e045e1ee
the creator of a non-shared D-Bus connection has to release the last
reference after closing for freeing.
Signed-off-by: NMarc Hartmayer <mhartmay@linux.ibm.com>
Reviewed-by: NBjoern Walk <bwalk@linux.ibm.com>
Reviewed-by: NBoris Fiuczynski <fiuczy@linux.ibm.com>
Reviewed-by: NStefan Zimmermann <stzi@linux.ibm.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

Grab a ref for info->bus (a DBus connection) as long as the while loop
is running. With the grabbed reference it is ensured that info->bus
isn't freed as long as the while loop is executed. This is necessary
as it's allowed to drop the last ref for the bus connection in a
handler.

There was already a bug of this kind in libdbus itself:
https://bugs.freedesktop.org/show_bug.cgi?id=15635.
Signed-off-by: NMarc Hartmayer <mhartmay@linux.ibm.com>
Reviewed-by: NBoris Fiuczynski <fiuczy@linux.ibm.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

The only place where VIR_DOMAIN_EVENT_RESUMED should be generated is the
RESUME event handler to make sure we don't generate duplicate events or
state changes. In the worse case the duplicity can revert or cover
changes done by other event handlers.

For example, after QEMU sent RESUME, BLOCK_IO_ERROR, and STOP events
we could happily mark the domain as running and report
VIR_DOMAIN_EVENT_RESUMED to registered clients.

https://bugzilla.redhat.com/show_bug.cgi?id=1612943Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

Thanks to the previous commit the RESUME event handler knows what reason
should be used when changing the domain state to VIR_DOMAIN_RUNNING, but
the emitted VIR_DOMAIN_EVENT_RESUMED event still uses a generic
VIR_DOMAIN_EVENT_RESUMED_UNPAUSED detail. Luckily, the event detail can
be easily deduced from the running reason, which saves us from having to
pass one more value to the handler.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

Whenever we get the RESUME event from QEMU, we change the state of the
affected domain to VIR_DOMAIN_RUNNING with VIR_DOMAIN_RUNNING_UNPAUSED
reason. This is fine if the domain is resumed unexpectedly, but when we
sent "cont" to QEMU we usually have a better reason for the state
change. The better reason is used in qemuProcessStartCPUs which also
sets the domain state to running if qemuMonitorStartCPUs reports
success. Thus we may end up with two state updates in a row, but the
final reason is correct.

This patch is a preparation for dropping the state change done in
qemuMonitorStartCPUs for which we need to pass the actual running reason
to the RESUME event handler and use it there instead of
VIR_DOMAIN_RUNNING_UNPAUSED.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

This patch replaces some rather generic VIR_DOMAIN_RUNNING_UNPAUSED
reasons when changing domain state to running with more specific ones.
All of them are done when libvirtd reconnects to an existing domain
after being restarted and sees an unfinished migration or save.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

VIR_DOMAIN_EVENT_RESUMED_FROM_SNAPSHOT was defined but not used anywhere
in our event generation code. This fixes qemuDomainRevertToSnapshot to
properly report why the domain was resumed.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

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: NMark Asselstine <mark.asselstine@windriver.com>
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

With the introduction of cgroup v2 there are new names used with
cgroups based on which version is used:

    - legacy: cgroup v1
    - unified: cgroup v2
    - hybrid: cgroup v1 and cgroup v2

Let's use 'legacy' instead of 'cgroupv1' or 'controllers' in our code.
Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

They all need virCgroupV1GetMemoryUnlimitedKB() so it's easier to
move them in one commit.
Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>