https://bugzilla.redhat.com/show_bug.cgi?id=1204006 Commit e105dc9 fix setting vcpus for offline domain, but forget check if vm is active when pass VIR_DOMAIN_AFFECT_LIVE flags. # virsh setvcpus test3 4 --live error: Failed to create controller cpu for group: No such file or directory add a check if we pass VIR_DOMAIN_AFFECT_LIVE flags. Signed-off-by: Luyao Huang <lhuang(a)redhat.com&gt; --- src/qemu/qemu_driver.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index 6d9217b..40d2776 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -4888,6 +4888,12 @@ qemuDomainSetVcpusFlags(virDomainPtr dom, unsigned int nvcpus, goto cleanup; if (flags & VIR_DOMAIN_AFFECT_LIVE && !(flags & VIR_DOMAIN_VCPU_GUEST)) { + if (!virDomainObjIsActive(vm)) { + virReportError(VIR_ERR_OPERATION_INVALID, "%s", + _("domain is not running")); + goto endjob; + } + if (virCgroupNewEmulator(priv->cgroup, false, &cgroup_temp) < 0) goto endjob; -- 1.8.3.1