Re: [libvirt] Fix locking in qemudDomainMemoryStats

When adding domainMemoryStats API support for the qemu driver, I didn't follow the locking rules exactly. The job condition must be held when executing monitor commands. This corrects the segfaults I was seeing when calling domainMemoryStats in a multi-threaded environment. If this patch is accepted, I would also consider it a candidate for the 0.7.6 stable patch stream (if such a thing exists). Thanks.

Signed-off-by: Adam Litke <agl(a)us.ibm.com&gt; diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index b8b7916..a9023da 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -7526,6 +7526,9 @@ qemudDomainMemoryStats (virDomainPtr dom, goto cleanup; } + if (qemuDomainObjBeginJob(vm) < 0) + goto cleanup; + if (virDomainObjIsActive(vm)) { qemuDomainObjPrivatePtr priv = vm->privateData; qemuDomainObjEnterMonitor(vm); @@ -7536,6 +7539,9 @@ qemudDomainMemoryStats (virDomainPtr dom, "%s", _("domain is not running")); } + if (qemuDomainObjEndJob(vm) == 0) + vm = NULL; + cleanup: if (vm) virDomainObjUnlock(vm);