Citing from the changelog [1] * systemd now defaults to the "unified" cgroup hierarchy setup during build-time, i.e. -Ddefault-hierarchy=unified is now the build-time default. Previously, -Ddefault-hierarchy=hybrid was the default. This change reflects the fact that cgroupsv2 support has matured substantially in both systemd and in the kernel, and is clearly the way forward. Downstream production distributions might want to continue to use -Ddefault-hierarchy=hybrid (or even =legacy) for their builds as unfortunately the popular container managers have not caught up with the kernel API changes. Unfortunately, we still have quite a number of consumers for the legacy cgroupv1 hierarchy, one notable example is the libvirtd-lxc hypervisor. I see two options: (a) enable -Ddefault-hierarchy=hybrid per default, (b) introduce a use flag to enable hybrid setup in order to keep libvirt-lxc and other containerization hypervisors functional. [1] https://github.com/systemd/systemd/blob/master/NEWS
The bug has been referenced in the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=d2202248997bf8b8a025306b28a5a98969b016f7 commit d2202248997bf8b8a025306b28a5a98969b016f7 Author: Mike Gilbert <floppym@gentoo.org> AuthorDate: 2019-08-02 19:24:18 +0000 Commit: Mike Gilbert <floppym@gentoo.org> CommitDate: 2019-08-02 19:24:18 +0000 sys-apps/systemd: add cgroup-hybrid USE flag Bug: https://bugs.gentoo.org/691310 Package-Manager: Portage-2.3.70_p1, Repoman-2.3.16_p21 Signed-off-by: Mike Gilbert <floppym@gentoo.org> sys-apps/systemd/metadata.xml | 1 + sys-apps/systemd/{systemd-243_rc1.ebuild => systemd-243_rc1-r1.ebuild} | 3 ++- sys-apps/systemd/systemd-9999.ebuild | 3 ++- 3 files changed, 5 insertions(+), 2 deletions(-)
The bug has been referenced in the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=a5b2246874f8adbfe7745614296ece8adb2b23f0 commit a5b2246874f8adbfe7745614296ece8adb2b23f0 Author: Matthias Maier <tamiko@gentoo.org> AuthorDate: 2019-08-02 19:39:05 +0000 Commit: Matthias Maier <tamiko@gentoo.org> CommitDate: 2019-08-02 19:45:47 +0000 app-emulation/libvirt: block sys-apps/systemd[-cgroup-hypbrid(+)] For the time being we have to ensure that systemd is configured with hybrid cgroup layout. Otherwise libvirt-lxc ceases to work. Bug: https://bugs.gentoo.org/691310 Package-Manager: Portage-2.3.70, Repoman-2.3.16 Signed-off-by: Matthias Maier <tamiko@gentoo.org> app-emulation/libvirt/libvirt-5.2.0-r2.ebuild | 1 + app-emulation/libvirt/libvirt-5.5.0-r1.ebuild | 1 + app-emulation/libvirt/libvirt-9999.ebuild | 1 + 3 files changed, 3 insertions(+)
Also libvirt/qemu/kvm is broken for the same reason.
Same issue with docker, reported analogous Bug 691844
The bug has been referenced in the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=636ebd9472d94241da1961e631a2135d6d30ab23 commit 636ebd9472d94241da1961e631a2135d6d30ab23 Author: Matthias Maier <tamiko@gentoo.org> AuthorDate: 2019-08-13 05:52:08 +0000 Commit: Matthias Maier <tamiko@gentoo.org> CommitDate: 2019-08-13 05:52:36 +0000 app-emulation/libvirt: Always require cgroupv1 hierarchy It turns out that we need the cgroupv1 hierarchy also for non lxc related stuff. Fix dependency accordingly Bug: https://bugs.gentoo.org/691310 Package-Manager: Portage-2.3.71, Repoman-2.3.17 Signed-off-by: Matthias Maier <tamiko@gentoo.org> app-emulation/libvirt/libvirt-5.2.0-r2.ebuild | 2 +- app-emulation/libvirt/libvirt-5.5.0-r1.ebuild | 2 +- app-emulation/libvirt/libvirt-5.6.0.ebuild | 2 +- app-emulation/libvirt/libvirt-9999.ebuild | 2 +- 4 files changed, 4 insertions(+), 4 deletions(-)
Now I can't build app-emulation/libvirt with sys-apps/systemd < 243_rc1 anymore, cause it doesn't provide cgroup-hybrid useflag at all.
(In reply to Johannes Hirte from comment #6) > Now I can't build app-emulation/libvirt with sys-apps/systemd < 243_rc1 > anymore, cause it doesn't provide cgroup-hybrid useflag at all. The blocker is written to allow for that. If you are getting an error, please post it.
(In reply to Mike Gilbert from comment #7) > (In reply to Johannes Hirte from comment #6) > > Now I can't build app-emulation/libvirt with sys-apps/systemd < 243_rc1 > > anymore, cause it doesn't provide cgroup-hybrid useflag at all. > > The blocker is written to allow for that. If you are getting an error, > please post it. Seemed to be a side-effect with some other dependency and world-update. After restricting the update to libvirt (and direct dependencies), I wasn't able to reproduce. So please ignore.
(In reply to Johannes Hirte from comment #8) > [...] > > Seemed to be a side-effect with some other dependency and world-update. > After restricting the update to libvirt (and direct dependencies), I wasn't > able to reproduce. So please ignore. Unfortunately, the the blocker is not ideal in terms of conflict resolution (i.e. portage gets easily confused and does not necessarily show you the obvious solution (i.e. setting USE=cgroup-hybrid). There is unfortunately not much we can do about that :-(
libvirt is supposed to support cgroups v2 since v4.9.0: https://libvirt.org/news.html#v4.9.0 Is it possible to restrict the blocker to setups that use components of libvirt that still require cgroups v1?
Maybe replace the blocker with an ewarn?
According to the libvirt team all known cgroup bugs have been fixed since 5.8.0. Once I've managed to unwedge the build I'll give it a test.
I've tested virt-manager with KVM guests with a cg2 systemd and it worked fine. I need to lookup what's needed to test containers via libvirt.
Why is this bug resolved? How was it fixed?
(In reply to Fabian Henze from comment #14) > Why is this bug resolved? How was it fixed? Because we are now enforcing hybrid cgroup layout in systemd if you build libvirt with USE=lxc: lxc? ( !sys-apps/systemd[-cgroup-hybrid(+)] )
