This was found while researching the root cause of:
https://bugzilla.redhat.com/show_bug.cgi?id=670848
virDomainUnref should only be called with the lock held for the
virDomainObj in question. However, when a transient qemu domain gets
EOF on its monitor socket, it queues an event which frees the monitor,
which unref's the virDomainObj without first locking it. If another
thread has already locked the virDomainObj, the modification of the
refcount could potentially be corrupted. In an extreme case, it could
also be potentially unlocked by virDomainObjFree, thus left open to
modification by anyone else who would have otherwise waited for the
lock (not to mention the fact that they would be accessing freed
data!).
The solution is to have qemuMonitorFree lock the domain object right
before unrefing it. Since the caller to qemuMonitorFree doesn't expect
this lock to be held, if the refcount doesn't go all the way to 0,
qemuMonitorFree must unlock it after the unref.
Relax the restriction that the hash table key must be a string
by allowing an arbitrary hash code generator + comparison func
to be provided
* util/hash.c, util/hash.h: Allow any pointer as a key
* internal.h: Include stdbool.h as standard.
* conf/domain_conf.c, conf/domain_conf.c,
conf/nwfilter_params.c, nwfilter/nwfilter_gentech_driver.c,
nwfilter/nwfilter_gentech_driver.h, nwfilter/nwfilter_learnipaddr.c,
qemu/qemu_command.c, qemu/qemu_driver.c,
qemu/qemu_process.c, uml/uml_driver.c,
xen/xm_internal.c: s/char */void */ in hash callbacks
This is done for two reasons:
- we are getting very close to 64 flags which is the maximum we can use
with unsigned long long
- by using LL constants in enum we already violates C99 constraint that
enum values have to fit into int
Done mechanically with:
$ git grep -l '\bDEBUG0\? *(' | xargs -L1 sed -i 's/\bDEBUG0\? *(/VIR_&/'
followed by manual deletion of qemudDebug in daemon/libvirtd.c, along
with a single 'make syntax-check' fallout in the same file, and the
actual deletion in src/util/logging.h.
* src/util/logging.h (DEBUG, DEBUG0): Delete.
* daemon/libvirtd.h (qemudDebug): Likewise.
* global: Change remaining clients over to VIR_DEBUG counterpart.
Now that the virHash handling functions call virReportOOMError by
themselves when needed, users of the virHash API no longer need to
do it by themselves. Since users of the virHash API were not
consistently calling virReportOOMError after memory failures from
the virHash code, this has the added benefit of making OOM
reporting from this code more consistent and reliable.
Move the qemudStartVMDaemon and qemudShutdownVMDaemon
methods into a separate file, renaming them to
qemuProcessStart, qemuProcessStop. All helper methods
called by these are also moved & renamed to match
* src/Makefile.am: Add qemu_process.c/.h
* src/qemu/qemu_command.c: Add qemuDomainAssignPCIAddresses
* src/qemu/qemu_command.h: Add VNC port min/max
* src/qemu/qemu_domain.c, src/qemu/qemu_domain.h: Add
domain event queue helpers
* src/qemu/qemu_driver.c, src/qemu/qemu_driver.h: Remove
all QEMU process startup/shutdown functions
* src/qemu/qemu_process.c, src/qemu/qemu_process.h: Add
all QEMU process startup/shutdown functions