[Pkg-libvirt-maintainers] Bug#939983: error: Unable to read from '/sys/fs/cgroup/unified/machine/cgroup.controllers'

[Thorsten Glaser]

Package: libvirt-daemon
Version: 5.6.0-2
Severity: serious
Justification: unusable, no working workaround

tglase at tglase:~ $ alias wirrsh
wirrsh='virsh -c qemu:///system'
tglase at tglase:~ $ wirrsh start MirBSD
error: Failed to start domain MirBSD
error: Unable to read from '/sys/fs/cgroup/unified/machine/cgroup.controllers': No such file or directory

This might be related to #935734, but the workaround from there, to add…
	cgroup_controllers = [ ]
… to /etc/libvirt/qemu.conf, does not work any more.

-- System Information:
Debian Release: bullseye/sid
  APT prefers unreleased
  APT policy: (500, 'unreleased'), (500, 'buildd-unstable'), (500, 'unstable'), (100, 'experimental')
Architecture: x32 (x86_64)
Foreign Architectures: i386, amd64

Kernel: Linux 5.2.0-2-amd64 (SMP w/4 CPU cores)
Kernel taint flags: TAINT_FIRMWARE_WORKAROUND
Locale: LANG=C, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE=C (charmap=UTF-8)
Shell: /bin/sh linked to /bin/lksh
Init: sysvinit (via /sbin/init)

Versions of packages libvirt-daemon depends on:
ii  libblkid1           2.34-0.1
ii  libc6               2.28-10
ii  libcap-ng0          0.7.9-2+b1
ii  libdbus-1-3         1.12.16-1
ii  libdevmapper1.02.1  2:1.02.155-3
ii  libfuse2            2.9.9-2
ii  libgcc1             1:9.2.1-7
ii  libgnutls30         3.6.9-4
ii  libnetcf1           1:0.2.8-1+b2
ii  libparted2          3.2-26
ii  libpcap0.8          1.9.0-2
ii  libpciaccess0       0.14-1
ii  libselinux1         2.9-2+b2
ii  libudev1            242-7
ii  libvirt0            5.6.0-2
ii  libxml2             2.9.4+dfsg1-7+b3tarent1

Versions of packages libvirt-daemon recommends:
ii  libxml2-utils   2.9.4+dfsg1-7+b3tarent1
ii  netcat-openbsd  1.203-2
ii  qemu            1:4.1-1+b1

Versions of packages libvirt-daemon suggests:
pn  libvirt-daemon-driver-storage-gluster  <none>
pn  libvirt-daemon-driver-storage-rbd      <none>
pn  libvirt-daemon-driver-storage-zfs      <none>
ii  libvirt-daemon-system                  5.6.0-2
pn  numad                                  <none>

-- no debconf information