#1010469 lxc: as root, lxc-start fails to start with cgroups/cgfsng error setting up limits for devices

Package:
lxc
Source:
lxc
Description:
Linux Containers userspace tools
Submitter:
Julian Gilbey
Date:
2023-05-15 20:54:02 UTC
Severity:
normal
Tags:
#1010469#5
Date:
2022-05-01 15:03:09 UTC
From:
To:
(I realise that posting this on debian-devel [1] was probably not the
most appropriate place, as it's actually a bug report.)

I am not sure whether this is a bug in autopkgtest-build-lxc, a bug in
lxc itself or a user error.  Please feel free to redirect as
appropriate!

This is what I did:

Step 1: I installed the lxc and autopkgtest packages
That went smoothly.  (lxc version 1:4.0.11-1, autopkgtest version
5.21; autopkgtest was already installed, and I installed lxc from

Step 2: I ran the command "autopkgtest-build-lxc debian sid"
as root.  I got various warning messages to begin with:
lxc-create: autopkgtest-sid: storage/btrfs.c: btrfs_create: 938 Inappropriate ioctl for device - Failed to create btrfs subvolume "/var/lib/lxc/autopkgtest-sid/rootfs"
lxc-create: autopkgtest-sid: storage/zfs.c: zfs_create: 735 Failed to create zfs dataset "zfs:lxc/autopkgtest-sid": lxc-create: autopkgtest-sid: utils.c: run_command_internal: 1588
lxc-create: autopkgtest-sid: storage/lvm.c: do_lvm_create: 165 Failed to create logical volume "autopkgtest-sid":   Volume group "lxc" not found
  Cannot process volume group lxc
lxc-create: autopkgtest-sid: storage/lvm.c: lvm_create: 623 Error creating new logical volume "lvm:/dev/lxc/autopkgtest-sid" of size "1073741824 bytes"
<<<<<

after which things ran smoothly for a bit:
debootstrap is /usr/sbin/debootstrap
Checking cache download in /var/cache/lxc/debian/rootfs-sid-amd64 ...
Downloading debian minimal ...
I: Target architecture can be executed
I: Retrieving InRelease
[... downloading and installing base system ...]
I: Base system installed successfully.
Download complete.
<<<<<

but then there were lots of warning messages about libeatmydata.so
interspersed with information messages; I assume that these are mostly
harmless:

But then I received several fatal error messages:
lxc-start: autopkgtest-sid: lxccontainer.c: wait_on_daemonized_start: 867 Received container state "ABORTING" instead of "RUNNING"
lxc-start: autopkgtest-sid: tools/lxc_start.c: main: 306 The container failed to start
lxc-start: autopkgtest-sid: tools/lxc_start.c: main: 309 To get more details, run the container in foreground mode
lxc-start: autopkgtest-sid: tools/lxc_start.c: main: 311 Additional information can be obtained by setting the --logfile and --logpriority options
<<<<<

Since autopkgtest-build-lxc doesn't allow a --logfile option, I
attempted to start the container manually, using the command
  lxc-start -n autopkgtest-sid --logfile /tmp/lxc.log --logpriority INFO
and got the following warnings and errors in the log file (I've
excluded the INFO entries):
lxc-start autopkgtest-sid 20220501145802.680 NOTICE   conf - conf.c:lxc_setup:4450 - The container "autopkgtest-sid" is set up
lxc-start autopkgtest-sid 20220501145802.681 WARN     cgfsng - cgroups/cgfsng.c:get_hierarchy:142 - There is no useable devices controller
lxc-start autopkgtest-sid 20220501145802.681 ERROR    cgfsng - cgroups/cgfsng.c:cg_legacy_set_data:2675 - No such file or directory - Failed to setup limits for the "devices" controller. The controller seems to be unused by "cgfsng" cgroup driver or not enabled on the cgroup hierarchy
lxc-start autopkgtest-sid 20220501145802.681 ERROR    cgfsng - cgroups/cgfsng.c:cgfsng_setup_limits_legacy:2742 - No such file or directory - Failed to set "devices.deny" to "a"
lxc-start autopkgtest-sid 20220501145802.681 ERROR    start - start.c:lxc_spawn:1890 - Failed to setup legacy device cgroup controller limits
lxc-start autopkgtest-sid 20220501145802.681 ERROR    lxccontainer - lxccontainer.c:wait_on_daemonized_start:867 - Received container state "ABORTING" instead of "RUNNING"
lxc-start autopkgtest-sid 20220501145802.681 ERROR    lxc_start - tools/lxc_start.c:main:306 - The container failed to start
lxc-start autopkgtest-sid 20220501145802.681 ERROR    lxc_start - tools/lxc_start.c:main:309 - To get more details, run the container in foreground mode
lxc-start autopkgtest-sid 20220501145802.681 ERROR    lxc_start - tools/lxc_start.c:main:311 - Additional information can be obtained by setting the --logfile and --logpriority options
lxc-start autopkgtest-sid 20220501145802.682 ERROR    start - start.c:__lxc_start:2068 - Failed to spawn container "autopkgtest-sid"
lxc-start autopkgtest-sid 20220501145802.682 WARN     start - start.c:lxc_abort:1038 - No such process - Failed to send SIGKILL via pidfd 20 for process 389747
<<<<<

I found something like this reported at this GitHub issue against lxc:
https://github.com/lxc/lxc/issues/2268
so I followed the advice there and ran the commands:

mount -o remount,rw /sys/fs/cgroup
mkdir /sys/fs/cgroup/devices
mount -t cgroup devices -o devices /sys/fs/cgroup/devices
mount -o remount,ro /sys/fs/cgroup

But that seems to be really bad, as now systemd-logind.service seems
to have broken and cannot be restarted, so I don't recommend doing
that!

I've restarted my system and started again.  The above solution is
very bad at least partly because /sys/fs/cgroup is type cgroup2.  But
I still can't start the LXC container, which makes running autopkgtest
impossible.

I did read the Debian Wiki pages on LXC and the
/usr/share/doc/lxc/README.Debian.gz file, but to no avail.  (I do have
apparmor installed.)

Any help much appreciated!

Best wishes,

   Julian


[1] https://lists.debian.org/debian-devel/2022/04/msg00372.html

#1010469#10
Date:
2022-05-02 07:21:13 UTC
From:
To:
clone 1010437 -1
reassign -1 lxc 1:4.0.11-1
retitle -1 lxc: as root, lxc-start fails to start with cgroups/cgfsng error setting up limits for devices
retitle 1010437 autopkgtest-build-lxc: eatmydata gives lots of LD_PRELOAD warnings
thanks

I have now run the autopkgtest-build-lxc script "by hand" to see where
the issues are arising in the issue below, and I think there are two
separate things going on, hence splitting this bug report into two.
A few comments interspersed below.

This looks to be similar to
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=963508 so I wonder
whether the apparmor settings for lxc mean that LD_PRELOAD cannot be
used with lxc, and LD_PRELOAD is needed by eatmydata.  This is a minor
issue with autopkgtest-build-lxc; maybe it should just not try using
eatmydata, or maybe there is some way to change the lxc apparmor
settings (if indeed that is the thing preventing the use of
LD_PRELOAD) to allow eatmydata?  I don't know anything about apparmor,
so I am just speculating here.

This also happens when I create the lxc container manually (as root),
using the recipe in autopkgtest-build-lxc:
  lxc-create -B best --name=autopkgtest-unstable -t debian -- -r unstable
the resulting container fails to start in the same way as just
described (when lxc-start is run as root).

This is the bug report against lxc.

Best wishes,

   Julian

#1010469#25
Date:
2022-05-06 07:15:58 UTC
From:
To:
Hi Paul and lxc maintainers,

lxc maintainers: sorry, I intended to copy in #1010469 in my previous
message but didn't do so; a possible cause of this bug is discussed
below

Yes, I was determined to get it to work!

I was thinking more of
https://bugs.debian.org/944389

And I'm on 1:4.0.11-1.  So perhaps there was a regression in this
regard?

Best wishes,

   Julian

#1010469#30
Date:
2022-05-06 11:53:35 UTC
From:
To:
No. I use this version and lxc just works for me. In fact everyone else
who is on testing/unstable is also using it. lxc also just works on a
clean VM. There is something wrong with your system that is causing
this, but it's in no way a general problem.

#1010469#35
Date:
2022-05-06 15:13:28 UTC
From:
To:
[excluding 1010437@bugs.d.o from reply list, as that's to do with
eatmydata]

It seems that you are right: I tried booting into Debian Live,
upgrading to testing and running lxc; it ran without a problem.

So now I'm in a quandry: despite installing lxc from scratch, and just
redoing so (purging the packages and removing all of the cached files,
/etc/lxc, /var/lib/lxc* and so on before reinstalling), I am still
experiencing the same problem.  I am running what I believe to be a
standard system - I first installed it in September 2020 or
thereabouts and have kept it up-to-date with testing ever since.  I
have no idea what might be causing this strange behaviour, and
therefore I have got no clue how to fix it.  I also don't know whether
what is wrong with my setup might affect other people as well.

If you have any suggestions of things I could look at on my system
(configuration files, other packages, ...) I'm all ears!

Many thanks,

   Julian

#1010469#40
Date:
2022-05-06 17:08:23 UTC
From:
To:
Are all packages recommended by lxc installed?
#1010469#45
Date:
2022-05-06 18:08:23 UTC
From:
To:
Yes, they are.  It's a standard Debian kernel (currently
linux-image-5.17.0-1-amd64 5.17.3-1).  I'm not aware of doing any
customisations that might have caused problems :(

/etc/lxc/default.conf is unmodified:

lxc.net.0.type = veth
lxc.net.0.link = lxcbr0
lxc.net.0.flags = up

lxc.apparmor.profile = generated
lxc.apparmor.allow_nesting = 1


and when I created a trial container, I get
/var/lib/lxc/debian-unstable-trial/config:

# Template used to create this container: /usr/share/lxc/templates/lxc-debian
# Parameters passed to the template: -r unstable
# For additional config options, please look at lxc.container.conf(5)

# Uncomment the following line to support nesting containers:
#lxc.include = /usr/share/lxc/config/nesting.conf
# (Be aware this has security implications)

lxc.net.0.type = veth
lxc.net.0.hwaddr = 00:16:3e:78:11:12
lxc.net.0.link = lxcbr0
lxc.net.0.flags = up
lxc.apparmor.profile = generated
lxc.apparmor.allow_nesting = 1
lxc.rootfs.path = dir:/var/lib/lxc/debian-unstable-trial/rootfs

# Common configuration
lxc.include = /usr/share/lxc/config/debian.common.conf

# Container specific configuration
lxc.tty.max = 4
lxc.uts.name = debian-unstable-trial
lxc.arch = amd64
lxc.pty.max = 1024


I've no idea if that is of any help.

Thanks!

   Julian

#1010469#50
Date:
2022-05-11 18:03:54 UTC
From:
To:
I could not find anything wrong in those. I'm sorry but I don't know
what's wrong with your system. can you debug to check what is the exact
point where it fails to start a container?

#1010469#55
Date:
2022-05-11 20:45:23 UTC
From:
To:
Thanks Antonio!

Here's a log file with logpriority at DEBUG; I've no idea if this will
help.  I'm so stumped.  I wondered if it was perhaps some extra kernel
modules (using dkms) causing the problem, so I've purged those and
rebooted, but it didn't help.

Something seems to be confused with the cgroups.  Here's the result of
mount | grep cgroup:
cgroup2 on /sys/fs/cgroup type cgroup2 (rw,nosuid,nodev,noexec,relatime)
none on /sys/fs/cgroup/net_cls type cgroup (rw,relatime,net_cls)

And ls /sys/fs/cgroup gives:

cgroup.controllers	dev-hugepages.mount  misc.capacity
cgroup.max.depth	dev-mqueue.mount     net_cls
cgroup.max.descendants	init.scope	     proc-fs-nfsd.mount
cgroup.procs		io.cost.model	     proc-sys-fs-binfmt_misc.mount
cgroup.stat		io.cost.qos	     sys-fs-fuse-connections.mount
cgroup.subtree_control	io.pressure	     sys-kernel-config.mount
cgroup.threads		io.stat		     sys-kernel-debug.mount
cpu.pressure		lxc.pivot	     sys-kernel-tracing.mount
cpuset.cpus.effective	memory.numa_stat     system.slice
cpuset.mems.effective	memory.pressure      user.slice
cpu.stat		memory.stat

Ho hum :-/

   Julian


lxc-start debian-unstable-trial 20220511204109.279 INFO     lxccontainer - lxccontainer.c:do_lxcapi_start:987 - Set process title to [lxc monitor] /var/lib/lxc debian-unstable-trial
lxc-start debian-unstable-trial 20220511204109.280 DEBUG    lxccontainer - lxccontainer.c:wait_on_daemonized_start:848 - First child 502040 exited
lxc-start debian-unstable-trial 20220511204109.280 INFO     lsm - lsm/lsm.c:lsm_init_static:38 - Initialized LSM security driver AppArmor
lxc-start debian-unstable-trial 20220511204109.281 DEBUG    seccomp - seccomp.c:parse_config_v2:656 - Host native arch is [3221225534]
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:parse_config_v2:807 - Processing "reject_force_umount  # comment this to allow umount -f;  not recommended"
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:do_resolve_add_rule:524 - Set seccomp rule to reject force umounts
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:do_resolve_add_rule:524 - Set seccomp rule to reject force umounts
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:do_resolve_add_rule:524 - Set seccomp rule to reject force umounts
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:parse_config_v2:807 - Processing "[all]"
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:parse_config_v2:807 - Processing "kexec_load errno 1"
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:do_resolve_add_rule:564 - Adding native rule for syscall[246:kexec_load] action[327681:errno] arch[0]
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:do_resolve_add_rule:564 - Adding compat rule for syscall[246:kexec_load] action[327681:errno] arch[1073741827]
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:do_resolve_add_rule:564 - Adding compat rule for syscall[246:kexec_load] action[327681:errno] arch[1073741886]
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:parse_config_v2:807 - Processing "open_by_handle_at errno 1"
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:do_resolve_add_rule:564 - Adding native rule for syscall[304:open_by_handle_at] action[327681:errno] arch[0]
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:do_resolve_add_rule:564 - Adding compat rule for syscall[304:open_by_handle_at] action[327681:errno] arch[1073741827]
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:do_resolve_add_rule:564 - Adding compat rule for syscall[304:open_by_handle_at] action[327681:errno] arch[1073741886]
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:parse_config_v2:807 - Processing "init_module errno 1"
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:do_resolve_add_rule:564 - Adding native rule for syscall[175:init_module] action[327681:errno] arch[0]
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:do_resolve_add_rule:564 - Adding compat rule for syscall[175:init_module] action[327681:errno] arch[1073741827]
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:do_resolve_add_rule:564 - Adding compat rule for syscall[175:init_module] action[327681:errno] arch[1073741886]
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:parse_config_v2:807 - Processing "finit_module errno 1"
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:do_resolve_add_rule:564 - Adding native rule for syscall[313:finit_module] action[327681:errno] arch[0]
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:do_resolve_add_rule:564 - Adding compat rule for syscall[313:finit_module] action[327681:errno] arch[1073741827]
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:do_resolve_add_rule:564 - Adding compat rule for syscall[313:finit_module] action[327681:errno] arch[1073741886]
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:parse_config_v2:807 - Processing "delete_module errno 1"
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:do_resolve_add_rule:564 - Adding native rule for syscall[176:delete_module] action[327681:errno] arch[0]
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:do_resolve_add_rule:564 - Adding compat rule for syscall[176:delete_module] action[327681:errno] arch[1073741827]
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:do_resolve_add_rule:564 - Adding compat rule for syscall[176:delete_module] action[327681:errno] arch[1073741886]
lxc-start debian-unstable-trial 20220511204109.281 INFO     seccomp - seccomp.c:parse_config_v2:1017 - Merging compat seccomp contexts into main context
lxc-start debian-unstable-trial 20220511204109.511 INFO     start - start.c:lxc_init:883 - Container "debian-unstable-trial" is initialized
lxc-start debian-unstable-trial 20220511204109.531 INFO     cgfsng - cgroups/cgfsng.c:cgfsng_monitor_create:1028 - The monitor process uses "lxc.monitor.debian-unstable-trial" as cgroup
lxc-start debian-unstable-trial 20220511204109.531 DEBUG    storage - storage/storage.c:get_storage_by_name:209 - Detected rootfs type "dir"
lxc-start debian-unstable-trial 20220511204109.532 INFO     cgfsng - cgroups/cgfsng.c:cgfsng_payload_create:1136 - The container process uses "lxc.payload.debian-unstable-trial" as inner and "lxc.payload.debian-unstable-trial" as limit cgroup
lxc-start debian-unstable-trial 20220511204109.534 INFO     start - start.c:lxc_spawn:1759 - Cloned CLONE_NEWNS
lxc-start debian-unstable-trial 20220511204109.534 INFO     start - start.c:lxc_spawn:1759 - Cloned CLONE_NEWPID
lxc-start debian-unstable-trial 20220511204109.534 INFO     start - start.c:lxc_spawn:1759 - Cloned CLONE_NEWUTS
lxc-start debian-unstable-trial 20220511204109.534 INFO     start - start.c:lxc_spawn:1759 - Cloned CLONE_NEWIPC
lxc-start debian-unstable-trial 20220511204109.534 INFO     start - start.c:lxc_spawn:1759 - Cloned CLONE_NEWNET
lxc-start debian-unstable-trial 20220511204109.534 DEBUG    start - start.c:lxc_try_preserve_namespace:139 - Preserved mnt namespace via fd 21 and stashed path as mnt:/proc/502041/fd/21
lxc-start debian-unstable-trial 20220511204109.534 DEBUG    start - start.c:lxc_try_preserve_namespace:139 - Preserved pid namespace via fd 22 and stashed path as pid:/proc/502041/fd/22
lxc-start debian-unstable-trial 20220511204109.534 DEBUG    start - start.c:lxc_try_preserve_namespace:139 - Preserved uts namespace via fd 23 and stashed path as uts:/proc/502041/fd/23
lxc-start debian-unstable-trial 20220511204109.534 DEBUG    start - start.c:lxc_try_preserve_namespace:139 - Preserved ipc namespace via fd 24 and stashed path as ipc:/proc/502041/fd/24
lxc-start debian-unstable-trial 20220511204109.534 DEBUG    start - start.c:lxc_try_preserve_namespace:139 - Preserved net namespace via fd 25 and stashed path as net:/proc/502041/fd/25
lxc-start debian-unstable-trial 20220511204109.534 INFO     cgfsng - cgroups/cgfsng.c:cgfsng_setup_limits_legacy:2749 - Limits for the legacy cgroup hierarchies have been setup
lxc-start debian-unstable-trial 20220511204109.534 WARN     cgfsng - cgroups/cgfsng.c:cgfsng_setup_limits:2809 - Invalid argument - Ignoring cgroup2 limits on legacy cgroup system
lxc-start debian-unstable-trial 20220511204109.534 INFO     start - start.c:do_start:1206 - Unshared CLONE_NEWCGROUP
lxc-start debian-unstable-trial 20220511204109.542 INFO     network - network.c:netdev_configure_server_veth:655 - Retrieved mtu 1500 from lxcbr0
lxc-start debian-unstable-trial 20220511204109.557 INFO     network - network.c:netdev_configure_server_veth:720 - Attached "vethS9TtPh" to bridge "lxcbr0"
lxc-start debian-unstable-trial 20220511204109.557 DEBUG    network - network.c:netdev_configure_server_veth:851 - Instantiated veth tunnel "vethS9TtPh <--> vethVbX9aI"
lxc-start debian-unstable-trial 20220511204109.558 DEBUG    conf - conf.c:lxc_mount_rootfs:1423 - Mounted rootfs "/var/lib/lxc/debian-unstable-trial/rootfs" onto "/usr/lib/x86_64-linux-gnu/lxc/rootfs" with options "(null)"
lxc-start debian-unstable-trial 20220511204109.558 INFO     conf - conf.c:setup_utsname:866 - Set hostname to "debian-unstable-trial"
lxc-start debian-unstable-trial 20220511204109.558 INFO     network - network.c:lxc_setup_network_in_child_namespaces:4005 - Finished setting up network devices with caller assigned names
lxc-start debian-unstable-trial 20220511204109.583 DEBUG    network - network.c:setup_hw_addr:3807 - Mac address "00:16:3e:98:ce:14" on "eth0" has been setup
lxc-start debian-unstable-trial 20220511204109.583 DEBUG    network - network.c:lxc_network_setup_in_child_namespaces_common:3948 - Network device "eth0" has been setup
lxc-start debian-unstable-trial 20220511204109.583 INFO     network - network.c:lxc_setup_network_in_child_namespaces:4021 - Finished setting up network devices with kernel assigned names
lxc-start debian-unstable-trial 20220511204109.583 INFO     conf - conf.c:mount_autodev:1206 - Preparing "/dev"
lxc-start debian-unstable-trial 20220511204109.583 INFO     conf - conf.c:mount_autodev:1267 - Prepared "/dev"
lxc-start debian-unstable-trial 20220511204109.583 DEBUG    conf - conf.c:lxc_mount_auto_mounts:733 - Invalid argument - Tried to ensure procfs is unmounted
lxc-start debian-unstable-trial 20220511204109.584 DEBUG    conf - conf.c:lxc_mount_auto_mounts:756 - Invalid argument - Tried to ensure sysfs is unmounted
lxc-start debian-unstable-trial 20220511204109.584 DEBUG    conf - conf.c:mount_entry:2403 - Remounting "/sys/fs/fuse/connections" on "/usr/lib/x86_64-linux-gnu/lxc/rootfs/sys/fs/fuse/connections" to respect bind or remount options
lxc-start debian-unstable-trial 20220511204109.584 DEBUG    conf - conf.c:mount_entry:2422 - Flags for "/sys/fs/fuse/connections" were 4110, required extra flags are 14
lxc-start debian-unstable-trial 20220511204109.584 DEBUG    conf - conf.c:mount_entry:2466 - Mounted "/sys/fs/fuse/connections" on "/usr/lib/x86_64-linux-gnu/lxc/rootfs/sys/fs/fuse/connections" with filesystem type "none"
lxc-start debian-unstable-trial 20220511204109.584 DEBUG    conf - conf.c:mount_entry:2466 - Mounted "proc" on "/usr/lib/x86_64-linux-gnu/lxc/rootfs/dev/.lxc/proc" with filesystem type "proc"
lxc-start debian-unstable-trial 20220511204109.584 DEBUG    conf - conf.c:mount_entry:2466 - Mounted "sys" on "/usr/lib/x86_64-linux-gnu/lxc/rootfs/dev/.lxc/sys" with filesystem type "sysfs"
lxc-start debian-unstable-trial 20220511204109.584 INFO     conf - conf.c:run_script_argv:337 - Executing script "/usr/share/lxcfs/lxc.mount.hook" for container "debian-unstable-trial", config section "lxc"
lxc-start debian-unstable-trial 20220511204109.652 INFO     conf - conf.c:lxc_fill_autodev:1304 - Populating "/dev"
lxc-start debian-unstable-trial 20220511204109.652 DEBUG    conf - conf.c:lxc_fill_autodev:1313 - Created device node "full"
lxc-start debian-unstable-trial 20220511204109.652 DEBUG    conf - conf.c:lxc_fill_autodev:1313 - Created device node "null"
lxc-start debian-unstable-trial 20220511204109.652 DEBUG    conf - conf.c:lxc_fill_autodev:1313 - Created device node "random"
lxc-start debian-unstable-trial 20220511204109.652 DEBUG    conf - conf.c:lxc_fill_autodev:1313 - Created device node "tty"
lxc-start debian-unstable-trial 20220511204109.652 DEBUG    conf - conf.c:lxc_fill_autodev:1313 - Created device node "urandom"
lxc-start debian-unstable-trial 20220511204109.652 DEBUG    conf - conf.c:lxc_fill_autodev:1313 - Created device node "zero"
lxc-start debian-unstable-trial 20220511204109.652 INFO     conf - conf.c:lxc_fill_autodev:1392 - Populated "/dev"
lxc-start debian-unstable-trial 20220511204109.652 INFO     conf - conf.c:lxc_transient_proc:3757 - Caller's PID is 1; /proc/self points to 1
lxc-start debian-unstable-trial 20220511204109.652 DEBUG    conf - conf.c:lxc_setup_devpts_child:1738 - Attached detached devpts mount 24 to 22/pts
lxc-start debian-unstable-trial 20220511204109.652 DEBUG    conf - conf.c:lxc_setup_devpts_child:1824 - Created "/dev/ptmx" file as bind mount target
lxc-start debian-unstable-trial 20220511204109.652 DEBUG    conf - conf.c:lxc_setup_devpts_child:1831 - Bind mounted "/dev/pts/ptmx" to "/dev/ptmx"
lxc-start debian-unstable-trial 20220511204109.652 DEBUG    conf - conf.c:lxc_allocate_ttys:1092 - Created tty with ptx fd 26 and pty fd 27 and index 1
lxc-start debian-unstable-trial 20220511204109.652 DEBUG    conf - conf.c:lxc_allocate_ttys:1092 - Created tty with ptx fd 28 and pty fd 29 and index 2
lxc-start debian-unstable-trial 20220511204109.652 DEBUG    conf - conf.c:lxc_allocate_ttys:1092 - Created tty with ptx fd 30 and pty fd 31 and index 3
lxc-start debian-unstable-trial 20220511204109.652 DEBUG    conf - conf.c:lxc_allocate_ttys:1092 - Created tty with ptx fd 32 and pty fd 33 and index 4
lxc-start debian-unstable-trial 20220511204109.652 INFO     conf - conf.c:lxc_allocate_ttys:1097 - Finished creating 4 tty devices
lxc-start debian-unstable-trial 20220511204109.652 DEBUG    conf - conf.c:lxc_setup_ttys:1056 - Bind mounted "" onto "tty1"
lxc-start debian-unstable-trial 20220511204109.652 DEBUG    conf - conf.c:lxc_setup_ttys:1056 - Bind mounted "" onto "tty2"
lxc-start debian-unstable-trial 20220511204109.652 DEBUG    conf - conf.c:lxc_setup_ttys:1056 - Bind mounted "" onto "tty3"
lxc-start debian-unstable-trial 20220511204109.652 DEBUG    conf - conf.c:lxc_setup_ttys:1056 - Bind mounted "" onto "tty4"
lxc-start debian-unstable-trial 20220511204109.653 INFO     conf - conf.c:lxc_setup_ttys:1063 - Finished setting up 4 /dev/tty<N> device(s)
lxc-start debian-unstable-trial 20220511204109.654 INFO     conf - conf.c:setup_personality:1904 - Set personality to "0lx0"
lxc-start debian-unstable-trial 20220511204109.654 DEBUG    conf - conf.c:capabilities_deny:3187 - Dropped mac_admin (33) capability
lxc-start debian-unstable-trial 20220511204109.654 DEBUG    conf - conf.c:capabilities_deny:3187 - Dropped mac_override (32) capability
lxc-start debian-unstable-trial 20220511204109.654 DEBUG    conf - conf.c:capabilities_deny:3187 - Dropped sys_time (25) capability
lxc-start debian-unstable-trial 20220511204109.654 DEBUG    conf - conf.c:capabilities_deny:3187 - Dropped sys_module (16) capability
lxc-start debian-unstable-trial 20220511204109.654 DEBUG    conf - conf.c:capabilities_deny:3187 - Dropped sys_rawio (17) capability
lxc-start debian-unstable-trial 20220511204109.654 DEBUG    conf - conf.c:capabilities_deny:3190 - Capabilities have been setup
lxc-start debian-unstable-trial 20220511204109.654 NOTICE   conf - conf.c:lxc_setup:4450 - The container "debian-unstable-trial" is set up
lxc-start debian-unstable-trial 20220511204109.654 INFO     apparmor - lsm/apparmor.c:apparmor_process_label_set_at:1186 - Set AppArmor label to "lxc-debian-unstable-trial_</var/lib/lxc>//&:lxc-debian-unstable-trial_<-var-lib-lxc>:"
lxc-start debian-unstable-trial 20220511204109.654 INFO     apparmor - lsm/apparmor.c:apparmor_process_label_set:1231 - Changed AppArmor profile to lxc-debian-unstable-trial_</var/lib/lxc>//&:lxc-debian-unstable-trial_<-var-lib-lxc>:
lxc-start debian-unstable-trial 20220511204109.655 WARN     cgfsng - cgroups/cgfsng.c:get_hierarchy:142 - There is no useable devices controller
lxc-start debian-unstable-trial 20220511204109.655 ERROR    cgfsng - cgroups/cgfsng.c:cg_legacy_set_data:2675 - No such file or directory - Failed to setup limits for the "devices" controller. The controller seems to be unused by "cgfsng" cgroup driver or not enabled on the cgroup hierarchy
lxc-start debian-unstable-trial 20220511204109.655 ERROR    cgfsng - cgroups/cgfsng.c:cgfsng_setup_limits_legacy:2742 - No such file or directory - Failed to set "devices.deny" to "a"
lxc-start debian-unstable-trial 20220511204109.655 ERROR    start - start.c:lxc_spawn:1890 - Failed to setup legacy device cgroup controller limits
lxc-start debian-unstable-trial 20220511204109.655 DEBUG    network - network.c:lxc_delete_network:4159 - Deleted network devices
lxc-start debian-unstable-trial 20220511204109.655 ERROR    lxccontainer - lxccontainer.c:wait_on_daemonized_start:867 - Received container state "ABORTING" instead of "RUNNING"
lxc-start debian-unstable-trial 20220511204109.655 ERROR    lxc_start - tools/lxc_start.c:main:306 - The container failed to start
lxc-start debian-unstable-trial 20220511204109.655 ERROR    lxc_start - tools/lxc_start.c:main:309 - To get more details, run the container in foreground mode
lxc-start debian-unstable-trial 20220511204109.655 ERROR    lxc_start - tools/lxc_start.c:main:311 - Additional information can be obtained by setting the --logfile and --logpriority options
lxc-start debian-unstable-trial 20220511204109.655 ERROR    start - start.c:__lxc_start:2068 - Failed to spawn container "debian-unstable-trial"
lxc-start debian-unstable-trial 20220511204109.655 WARN     start - start.c:lxc_abort:1038 - No such process - Failed to send SIGKILL via pidfd 20 for process 502047
lxc-start debian-unstable-trial 20220511204109.900 INFO     conf - conf.c:run_script_argv:337 - Executing script "/usr/share/lxcfs/lxc.reboot.hook" for container "debian-unstable-trial", config section "lxc"

#1010469#60
Date:
2022-05-31 11:12:55 UTC
From:
To:
tags 1010469 unreproducible
fixed 1010469 1:4.0.11-1
thanks

I decided to reinstall my system from scratch, and now this bug has
gone away.  So as no-one else could reproduce it and I have no idea
what has changed on my system as a result of reinstalling, I'm closing
it with an "unreproducible" tag.

Thanks for your help along the way!

Best wishes,

   Julian

#1010469#69
Date:
2022-06-08 08:50:18 UTC
From:
To:
notfixed 1010469 1:4.0.11-1
thanks

Oh dear, oh dear, oh dear.  It's just happened again.

I am so completely stumped by this one.

   Julian

#1010469#76
Date:
2022-08-01 20:44:16 UTC
From:
To:
Julian Gilbey <jdg@debian.org> wrote on 08/06/2022 at 10:50:18+0200:

What apparmor profile are you trying to run your container with?

#1010469#81
Date:
2022-08-08 14:47:08 UTC
From:
To:
Dear Pierre-Elliott,

I'm not sure which profile I'm using; I just installed lxc and am
using whatever the default is.

Looking at /var/lib/lxc/containername/config, I see the lines:

lxc.apparmor.profile = generated
lxc.apparmor.allow_nesting = 1

which hopefully means something to you!

Best wishes,

   Julian

#1010469#86
Date:
2023-02-06 22:56:51 UTC
From:
To:
Julian Gilbey <jdg@debian.org> wrote on 08/08/2022 at 15:47:08+0100:

Hrmpf, this one slipped out of my todolist, I'm sorry for this, this is
bad.

When you indeed reinstalled your system, which version of Debian did you
install?

Did you do anything specific before things turned bad again?

Cheers,

#1010469#91
Date:
2023-05-11 14:41:46 UTC
From:
To:
Hi Pierre-Elliott,

I was using debian testing (whatever state it was in at the time).

I've just tried reinstalling lxc from scratch with the current debian
testing.  I haven't been able to get as far as reproducing this error,
as I've hit a different snag:

# lxc-create -n debian-sid -t download -- -d debian -r sid -a amd64
# lxc-start -n debian-sid --logfile /tmp/lxc.log --logpriority DEBUG
lxc-start: debian-sid: ../src/lxc/lxccontainer.c: wait_on_daemonized_start: 878 Received container state "ABORTING" instead of "RUNNING"
lxc-start: debian-sid: ../src/lxc/tools/lxc_start.c: main: 306 The container failed to start
lxc-start: debian-sid: ../src/lxc/tools/lxc_start.c: main: 309 To get more details, run the container in foreground mode
lxc-start: debian-sid: ../src/lxc/tools/lxc_start.c: main: 311 Additional information can be obtained by setting the --logfile and --logpriority options

The resulting log file contains the cryptic error messages:

lxc-start debian-sid 20230511122856.360 ERROR    network - ../src/lxc/network.c:netdev_configure_server_veth:711 - No such file or directory - Failed to attach "vethQ4rt4x" to bridge "lxcbr0", bridge interface doesn't exist

That's super-weird; I have no idea what "vethQ4rt4x" is meant to mean.
I think this should probably be a separate bug report, though.
Despite some web searching, I have no idea how to fix this problem,
but I now can't use lxc at all :( I think it's something about lxc-net
not connecting the bridging device to the correct network device
(which in my case is enp5s0).

Best wishes,

   Julian

#1010469#96
Date:
2023-05-11 21:59:41 UTC
From:
To:
Julian Gilbey <jdg@debian.org> wrote on 11/05/2023 at 16:41:46+0200:
the LXC container to get network.

Inside the container it'll be eth0, outside it's a veth intervace, named
veth$RANDOM stuff.

The issue is in the message: you configured the container to bind this
interface on a bridge named lxcbr0 that doesn't seem to exist on the
host.

enp5s0 is a physical interface, bridging a container directly on it
might not achieve what you expect.

The usual way is to either use the lxc-net service, or to create a
manual bridge (with network/interfaces or systemd-networkd config),
allow forwarding on it and the physical interface, and bind the
containers on it.

You will find some doc on LXC network configuration on LXC's website. :)

#1010469#101
Date:
2023-05-12 09:39:33 UTC
From:
To:
Thanks so much for the quick response, that's really helpful!

Unfortunately, this doesn't seem to be the issue, though:

# systemctl status lxc-net.service
● lxc-net.service - LXC network bridge setup
     Loaded: loaded (/lib/systemd/system/lxc-net.service; enabled; preset: enab>
     Active: active (exited) since Thu 2023-05-11 20:35:48 BST; 13h ago
       Docs: man:lxc
    Process: 81843 ExecStart=/usr/libexec/lxc/lxc-net start (code=exited, statu>
   Main PID: 81843 (code=exited, status=0/SUCCESS)
      Tasks: 1 (limit: 76868)
     Memory: 1.3M
        CPU: 70ms
     CGroup: /system.slice/lxc-net.service
             └─81884 dnsmasq --conf-file=/dev/null -u dnsmasq --strict-order -->

May 11 20:35:48 euler systemd[1]: Starting lxc-net.service - LXC network bridge>
May 11 20:35:48 euler dnsmasq[81884]: started, version 2.89 cachesize 150
May 11 20:35:48 euler dnsmasq[81884]: compile time options: IPv6 GNU-getopt DBu>
May 11 20:35:48 euler dnsmasq-dhcp[81884]: DHCP, IP range 10.0.3.2 -- 10.0.3.25>
May 11 20:35:48 euler dnsmasq-dhcp[81884]: DHCP, sockets bound exclusively to i>
May 11 20:35:48 euler dnsmasq[81884]: reading /etc/resolv.conf
May 11 20:35:48 euler dnsmasq[81884]: using nameserver 10.0.0.243#53
May 11 20:35:48 euler dnsmasq[81884]: read /etc/hosts - 7 names
May 11 20:35:48 euler systemd[1]: Finished lxc-net.service - LXC network bridge>

And with some details snipped:

# ifconfig
enp5s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet [...]  netmask 255.255.255.0  broadcast 192.168.0.255
        inet6 [...]  prefixlen 64  scopeid 0x20<link>
        ether [...]  txqueuelen 1000  (Ethernet)
        [...]

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        [...]

lxcbr0: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
        inet 10.0.3.1  netmask 255.255.255.0  broadcast 10.0.3.255
        ether 00:16:3e:00:00:00  txqueuelen 1000  (Ethernet)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 0  bytes 0 (0.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

tun0: [...]

wlp3s0: [...]


# bridge vlan show
port              vlan-id
lxcbr0            1 PVID Egress Untagged



So lxc-net was established, and it still didn't work :(  (And yes,
I've just checked that lxc-start still fails.)  But maybe the bridge
is meant to be in the lxc container itself?


So I'm still totally stumped.

Any further ideas/suggestions/things to check would be welcomely
received!

Best wishes,

   Julian

#1010469#106
Date:
2023-05-12 09:54:30 UTC
From:
To:
Julian Gilbey <jdg@debian.org> wrote on 12/05/2023 at 11:39:33+0200:

What do you have in /etc/lxc/lxc-usernet ?

Also, what is your container config, please?

#1010469#111
Date:
2023-05-12 11:19:36 UTC
From:
To:
Hi Pierre-Elliott,

Thanks!  :-)

jdg veth lxcbr0 10

(But I'm trying to start the container as root, having su'd from jdg,
in case that's relevant.  And I have the subuid/subgid set up
correctly.)

I assume you mean /var/lib/lxc/debian-sid/config?  Here's the content
of this file:

# Template used to create this container: /usr/share/lxc/templates/lxc-download
# Parameters passed to the template: -d debian -r sid -a amd64
# For additional config options, please look at lxc.container.conf(5)

# Uncomment the following line to support nesting containers:
#lxc.include = /usr/share/lxc/config/nesting.conf
# (Be aware this has security implications)


# Distribution configuration
lxc.include = /usr/share/lxc/config/common.conf
lxc.arch = linux64

# Container specific configuration
lxc.apparmor.profile = generated
lxc.apparmor.allow_nesting = 1
lxc.rootfs.path = dir:/var/lib/lxc/debian-sid/rootfs
lxc.uts.name = debian-sid

# Network configuration
lxc.net.0.type = veth
lxc.net.0.link = lxcbr0
lxc.net.0.flags = up


As a non-expert, this looks fine, but there may be something awry
here.  I've had numerous lxc problems with my machine, and have no
idea why :(

Best wishes,

   Julian

#1010469#116
Date:
2023-05-15 09:37:32 UTC
From:
To:
OK, I rebooted my machine, and just tried again, and the bridge worked
fine.  So it was some random transient thing.  Who knows what?!

But now we're back to the original problem cgfsng problem (running
with --logpriority TRACE):

lxc-start debian-sid 20230515092650.376 WARN     cgfsng - ../src/lxc/cgroups/cgfsng.c:get_hierarchy:149 - There is no useable devices controller
lxc-start debian-sid 20230515092650.376 ERROR    cgfsng - ../src/lxc/cgroups/cgfsng.c:cg_legacy_set_data:3098 - No such file or directory - Failed to setup limits for the "devices" controller. The controller seems to be unused by "cgfsng" cgroup driver or not enabled on the cgroup hierarchy
lxc-start debian-sid 20230515092650.376 ERROR    cgfsng - ../src/lxc/cgroups/cgfsng.c:cgfsng_setup_limits_legacy:3165 - No such file or directory - Failed to set "devices.deny" to "a"
lxc-start debian-sid 20230515092650.376 ERROR    start - ../src/lxc/start.c:lxc_spawn:1893 - Failed to setup legacy device cgroup controller limits

The full log (with TRACE) is attached.

Running findmnt gives:

TARGET                         SOURCE         FSTYPE  OPTIONS
/                              /dev/nvme0n1p2 ext4    rw,noatime
├─/sys                         sysfs          sysfs   rw,nosuid,nodev,noexec,rel
│ ├─/sys/kernel/security       securityfs     securit rw,nosuid,nodev,noexec,rel
│ ├─/sys/fs/cgroup             cgroup2        cgroup2 rw,nosuid,nodev,noexec,rel
│ │ └─/sys/fs/cgroup/net_cls   none           cgroup  rw,relatime,net_cls
│ ├─/sys/fs/pstore             pstore         pstore  rw,nosuid,nodev,noexec,rel
[...]


Ho hum :(

Best wishes,

   Julian

#1010469#121
Date:
2023-05-15 20:05:37 UTC
From:
To:
Ah, success!  I followed the recipe on
https://wiki.debian.org/LXC/CGroupV2 referenced in
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=944389 (adding the
lines

lxc.cgroup.devices.allow =
lxc.cgroup.devices.deny =

to the end of /var/lib/lxc/debian-sid/config) and it now works.

But there's no mention of this in /usr/share/doc/lxc/README.Debian.gz,
and I don't need to do this on my other machine, so there's still
something weird going on on this machine.  Perhaps it's a hardware
thing?

Oh joys!

Best wishes,

   Julian

#1010469#126
Date:
2023-05-15 20:21:39 UTC
From:
To:
Julian Gilbey <jdg@debian.org> wrote on 15/05/2023 at 22:05:37+0200:

Ah, I don't remember seeing these logs before, maybe I forgot to ask for
a full trace, sorry.

Do you see anything in /var/log/audit or /var/log/syslog or
/var/log/kern.log about apparmor denies?

Cheers,

#1010469#131
Date:
2023-05-15 20:51:16 UTC
From:
To:
Hi Pierre-Elliott,

Thanks for all your time on this!

No, I don't think so; here's the relevant part of /var/log/syslog:

2023-05-15T21:47:21.645645+01:00 euler kernel: [94706.953337] audit: type=1400 audit(1684183641.640:92): apparmor="STATUS" operation="profile_load" profile="/usr/bin/lxc-start" name="lxc-debian-sid_</var/lib/lxc>" pid=547941 comm="apparmor_parser"
2023-05-15T21:47:21.741618+01:00 euler kernel: [94707.049379] lxcbr0: port 1(vethPUhTGL) entered blocking state
2023-05-15T21:47:21.741632+01:00 euler kernel: [94707.049385] lxcbr0: port 1(vethPUhTGL) entered disabled state
2023-05-15T21:47:21.741633+01:00 euler kernel: [94707.049489] device vethPUhTGL entered promiscuous mode
2023-05-15T21:47:21.741635+01:00 euler kernel: [94707.049738] lxcbr0: port 1(vethPUhTGL) entered blocking state
2023-05-15T21:47:21.741636+01:00 euler kernel: [94707.049741] lxcbr0: port 1(vethPUhTGL) entered forwarding state
2023-05-15T21:47:21.741637+01:00 euler kernel: [94707.049956] lxcbr0: port 1(vethPUhTGL) entered disabled state
2023-05-15T21:47:21.741637+01:00 euler kernel: [94707.050570] eth0: renamed from vethX4vupZ
2023-05-15T21:47:21.742023+01:00 euler NetworkManager[1647]: <info>  [1684183641.7416] manager: (vethPUhTGL): new Veth device (/org/freedesktop/NetworkManager/Devices/18)
2023-05-15T21:47:21.764024+01:00 euler NetworkManager[1647]: <info>  [1684183641.7639] device (vethPUhTGL): carrier: link connected
2023-05-15T21:47:21.764243+01:00 euler NetworkManager[1647]: <info>  [1684183641.7641] device (lxcbr0): carrier: link connected
2023-05-15T21:47:21.765623+01:00 euler kernel: [94707.072272] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
2023-05-15T21:47:21.765639+01:00 euler kernel: [94707.072351] IPv6: ADDRCONF(NETDEV_CHANGE): vethPUhTGL: link becomes ready
2023-05-15T21:47:21.765640+01:00 euler kernel: [94707.072481] lxcbr0: port 1(vethPUhTGL) entered blocking state
2023-05-15T21:47:21.765642+01:00 euler kernel: [94707.072487] lxcbr0: port 1(vethPUhTGL) entered forwarding state
2023-05-15T21:47:22.017893+01:00 euler kernel: [94707.323563] audit: type=1400 audit(1684183642.012:93): apparmor="STATUS" operation="profile_remove" profile="/usr/bin/lxc-start" name="lxc-debian-sid_</var/lib/lxc>" pid=547969 comm="apparmor_parser"
2023-05-15T21:47:22.085623+01:00 euler kernel: [94707.392045] lxcbr0: port 1(vethPUhTGL) entered disabled state
2023-05-15T21:47:22.085634+01:00 euler kernel: [94707.392996] device vethPUhTGL left promiscuous mode
2023-05-15T21:47:22.085635+01:00 euler kernel: [94707.393002] lxcbr0: port 1(vethPUhTGL) entered disabled state

and /var/log/kern.log, which seems very similar:

2023-05-15T21:47:21.645645+01:00 euler kernel: [94706.953337] audit: type=1400 a
udit(1684183641.640:92): apparmor="STATUS" operation="profile_load" profile="/us
r/bin/lxc-start" name="lxc-debian-sid_</var/lib/lxc>" pid=547941 comm="apparmor_
parser"
2023-05-15T21:47:21.741618+01:00 euler kernel: [94707.049379] lxcbr0: port 1(vet
hPUhTGL) entered blocking state
2023-05-15T21:47:21.741632+01:00 euler kernel: [94707.049385] lxcbr0: port 1(vet
hPUhTGL) entered disabled state
2023-05-15T21:47:21.741633+01:00 euler kernel: [94707.049489] device vethPUhTGL
entered promiscuous mode
2023-05-15T21:47:21.741635+01:00 euler kernel: [94707.049738] lxcbr0: port 1(vet
hPUhTGL) entered blocking state
2023-05-15T21:47:21.741636+01:00 euler kernel: [94707.049741] lxcbr0: port 1(vet
hPUhTGL) entered forwarding state
2023-05-15T21:47:21.741637+01:00 euler kernel: [94707.049956] lxcbr0: port 1(vethPUhTGL) entered disabled state
2023-05-15T21:47:21.741637+01:00 euler kernel: [94707.050570] eth0: renamed from vethX4vupZ
2023-05-15T21:47:21.765623+01:00 euler kernel: [94707.072272] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
2023-05-15T21:47:21.765639+01:00 euler kernel: [94707.072351] IPv6: ADDRCONF(NETDEV_CHANGE): vethPUhTGL: link becomes ready
2023-05-15T21:47:21.765640+01:00 euler kernel: [94707.072481] lxcbr0: port 1(vethPUhTGL) entered blocking state
2023-05-15T21:47:21.765642+01:00 euler kernel: [94707.072487] lxcbr0: port 1(vethPUhTGL) entered forwarding state
2023-05-15T21:47:22.017893+01:00 euler kernel: [94707.323563] audit: type=1400 audit(1684183642.012:93): apparmor="STATUS" operation="profile_remove" profile="/usr/bin/lxc-start" name="lxc-debian-sid_</var/lib/lxc>" pid=547969 comm="apparmor_parser"
2023-05-15T21:47:22.085623+01:00 euler kernel: [94707.392045] lxcbr0: port 1(vethPUhTGL) entered disabled state
2023-05-15T21:47:22.085634+01:00 euler kernel: [94707.392996] device vethPUhTGL left promiscuous mode
2023-05-15T21:47:22.085635+01:00 euler kernel: [94707.393002] lxcbr0: port 1(vethPUhTGL) entered disabled state

(and I don't have a /var/log/audit).

Hmmm....

   Julian