[PATCH 1/1] vircgroup: Cleanup nested cgroups

The introduction of nested cgroups used a little macro virCgroupGetNested() to retrieve the nested cgroup pointer, if one exists. But this macro isn't used when removing cgroups, resulting in some messages: Mar 25 20:55:17 fedora33 libvirtd[955]: unable to open '/sys/fs/cgroup/machine.slice/machine-qemu\x2d1\x2dguest.scope/': No such file or directory Mar 25 20:55:17 fedora33 libvirtd[955]: Failed to remove cgroup for guest That directory exists while the guest is running, as it was created by systemd/machined, so the code probably meant to open the libvirt/ subdirectory from that point. Similarly, there happen to be BPF-related file descriptors that don't get cleaned up in this process too, because they are anchored off the nested cgroup location: [test@fedora33 ~]# ls /proc/$(pgrep libvirtd)/fd/* | wc -l 35 [test@fedora33 ~]# virsh create guest.xml Domain 'guest' created from guest.xml [test@fedora33 ~]# ls /proc/$(pgrep libvirtd)/fd/* | wc -l 42 [test@fedora33 ~]# virsh shutdown guest Domain 'guest' is being shutdown [test@fedora33 ~]# ls /proc/$(pgrep libvirtd)/fd/* | wc -l 37 [test@fedora33 ~]# virsh create guest.xml Domain 'guest' created from guest.xml [test@fedora33 ~]# ls /proc/$(pgrep libvirtd)/fd/* | wc -l 44 [test@fedora33 ~]# virsh shutdown guest Domain 'guest' is being shutdown [test@fedora33 ~]# ls /proc/$(pgrep libvirtd)/fd/* | wc -l 39 Let's fix this by using the same macro when removing cgroups, so that it picks up the right structure and can remove the associated resources properly. Fixes: 184245f53b94 ("vircgroup: introduce nested cgroup to properly work with systemd") Signed-off-by: Eric Farman <farman(a)linux.ibm.com&gt; --- src/util/vircgroup.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/src/util/vircgroup.c b/src/util/vircgroup.c index 5b6097c335..e606cbfe0b 100644 --- a/src/util/vircgroup.c +++ b/src/util/vircgroup.c @@ -2613,11 +2613,12 @@ virCgroupRemoveRecursively(char *grppath) int virCgroupRemove(virCgroupPtr group) { + virCgroupPtr parent = virCgroupGetNested(group); size_t i; for (i = 0; i < VIR_CGROUP_BACKEND_TYPE_LAST; i++) { - if (group->backends[i]) { - int rc = group->backends[i]->remove(group); + if (parent->backends[i]) { + int rc = parent->backends[i]->remove(parent); if (rc < 0) return rc; } -- 2.25.1