[Pkg-libvirt-maintainers] Bug#983871: Bug#983871: error: internal error: failed to get cgroup backend for 'pathOfController'

[Dio Putra]

On Wed, 17 Nov 2021 16:30:54 +0100 Jonas =?ISO-8859-1?Q?Sch=E4fer?=
<jonas at wielicki.name> wrote:
> Hi again,
>
Hi Jonas.
> I did another test by pinning the bookworm packages (7.6.0-1) and testing
> those. They exhibit the same behaviour as the patched libvirt, that is: in
> some cases, virsh destroy will show an error, but the container will be
> removed cleanly nonetheless.
>
That's kind of odd, the version in bookworm should fix this issue because
it has been fixed on upstream version 7.3.0. And I can't reproducible this bug
again because I don't use LXC on libvirt quite heavily.
> This is an improvement over the previous situation, where it was impossible to
> destroy a domain.
>
> I'd thus suggest to move ahead with the patch, even if imperfect, as it then
> brings stable to the same state as testing in that regard (and I'll try to
> prepare a bug report for testing).
>
> kind regards,
> Jonas
>
> On Wed, 17 Nov 2021 16:10:57 +0100 Jonas Schäfer <jonas at wielicki.name> wrote:
> > Hi Guido,
> >
> > Thanks for your reply!
> >
> > On Wed, 17 Nov 2021 13:11:05 +0100 Guido Günther <gg at godiug.net> wrote:
> > > here's the missing link:
> > >
> > > https://salsa.debian.org/libvirt-team/libvirt/-/merge_requests/116
> >
> > I took the artifacts from there and did another test run. At first glance,
> > everything looked good, but then it failed on destruction of the domain
> again,
> > with:
> >
> > error: Unable to read from '/sys/fs/cgroup/machine.slice/machine-
> > lxc\x2d4078\x2drouter.scope/system.slice/cgroup.controllers': No such file or
> > directory
> >
> > The domain is afterward still fully cleaned up (the cgroup subtree under
> > machine.slice is gone completely), but the error message is still annoying.
> To
> > me it seems like the recursion in the libvirt code is racing against the
> > domain cleaning up after itself somehow, because I get different error
> messages
> > and sometimes it also succeeds:
> >
> > root at down ~ › virsh -c lxc:/// destroy router
> > Domain 'router' destroyed
> >
> > root at down ~ › virsh -c lxc:/// start router
> > Domain 'router' started
> >
> > root at down ~ › virsh -c lxc:/// destroy router
> > error: Failed to destroy domain 'router'
> > error: Unable to read from '/sys/fs/cgroup/machine.slice/machine-
> > lxc\x2d4078\x2drouter.scope/system.slice/cgroup.controllers': No such file or
> > directory
> >
> > root at down ~ › virsh -c lxc:/// start router
> > Domain 'router' started
> >
> > root at down ~ › virsh -c lxc:/// destroy router