[libvirt PATCH] qemu: fix crash in qemuDomainSetBlkioParameters without cgroups

[Pavel Hrdina]

If we don't have cgroups available and user tries to update blkio
parameters for running VM it will crash.

It should have been protected by the virCgroupHasController() check but
it was never called if the API was executed without any flags.

We call virDomainObjGetDefs() which sets `def` and `persistentDef` based
on the flags and these two variables should be used to figure out if we
need to update LIVE, CONFIG or both states.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1808293

Signed-off-by: Pavel Hrdina <phrdina at redhat.com>
---
 src/qemu/qemu_driver.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 07e9518a9b..8008da6d16 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -9356,7 +9356,7 @@ qemuDomainSetBlkioParameters(virDomainPtr dom,
     if (virDomainObjGetDefs(vm, flags, &def, &persistentDef) < 0)
         goto endjob;
 
-    if (flags & VIR_DOMAIN_AFFECT_LIVE) {
+    if (def) {
         if (!virCgroupHasController(priv->cgroup, VIR_CGROUP_CONTROLLER_BLKIO)) {
             virReportError(VIR_ERR_OPERATION_INVALID, "%s",
                            _("blkio cgroup isn't mounted"));
-- 
2.26.2