[1] closes gap in virDomainObjListRemove so that concurrent thread can not step in and obtain the domain while domain is temporary unlocked. But there is another gap exist: thread B - executes create API thread C - executes undefine API - thread A executes some job on domain - threads B and C obtains domain from list and wait for job condition - thread A finishes its job and C grabs job condition, removes domain from list and finishes - thread B grabs job condition and start the domain, unfortunately is not in the list already [1] commit c7d1c139ca3402e875002753952e80ce8054374e Author: Martin Kletzander <mkletzan@xxxxxxxxxx> Date: Thu Dec 11 11:14:08 2014 +0100 qemu: avoid rare race when undefining domain Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@xxxxxxxxxx> --- src/qemu/qemu_domainjob.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/src/qemu/qemu_domainjob.c b/src/qemu/qemu_domainjob.c index 1cddc7f2f0..cb20b798f7 100644 --- a/src/qemu/qemu_domainjob.c +++ b/src/qemu/qemu_domainjob.c @@ -849,6 +849,16 @@ qemuDomainObjBeginJobInternal(virQEMUDriver *driver, if (!nested && !qemuDomainNestedJobAllowed(&priv->job, job)) goto retry; + if (obj->removing) { + char uuidstr[VIR_UUID_STRING_BUFLEN]; + + virUUIDFormat(obj->def->uuid, uuidstr); + virReportError(VIR_ERR_NO_DOMAIN, + _("no domain with matching uuid '%s' (%s)"), + uuidstr, obj->def->name); + goto cleanup; + } + ignore_value(virTimeMillisNow(&now)); if (job) { -- 2.35.1