run-qemu.mount is restarted on upgrades

[Christian Ehrhardt ]

[ Impact ]

 * Due to dh_installsystemd handling mount units not correctly
   in jammy one is restarted on updates breaking the use case
   and potentially crashing binaries with shared objects loaded
   from that path

 * The fix removed the offending restart (in a minimal fashion) as we handle enable+start ourselves already anyway. We could remove more, but this is the smallest change and therefore more reviewable and maintainable.

[ Test Plan ]

 * apt install -y --reinstall qemu-block-extra; systemctl status run-qemu.mount; ls -laF /run/qemu/

 * bad case, mount unit got restarted, empty dir
 * good case, unit still up from before, content in the path

Example of the good case:
● run-qemu.mount - Prepare /run/qemu to allow still running qemu binaries of former builds (after package upgrades) to fallback-load modules from there
     Loaded: loaded (/proc/self/mountinfo; enabled; vendor preset: enabled)
     Active: active (mounted) since Fri 2024-01-26 13:30:56 UTC; 2 days ago
      Where: /run/qemu
       What: tmpfs
      Tasks: 0 (limit: 1171)
     Memory: 8.0K
        CPU: 2ms
     CGroup: /system.slice/run-qemu.mount

Jan 26 13:30:56 j-vm systemd[1]: Mounting Prepare /run/qemu to allow still running qemu binaries of former builds (after package upgrades) to fallback-load modules from there...
Jan 26 13:30:56 j-vm systemd[1]: Mounted Prepare /run/qemu to allow still running qemu binaries of former builds (after package upgrades) to fallback-load modules from there.
total 0
drwxr-xr-x 3 root root 60 Jan 29 13:27 ./
drwxr-xr-x 29 root root 920 Jan 29 07:00 ../
drwxr-xr-x 2 root root 140 Jan 29 13:27 Debian_1_6.2+dfsg-2ubuntu6.17~jammyppa3/

[ Where problems could occur ]

 * This exclusively changes the mount unit handling which currently is useless by being restarted, no chance to regress that

 * The other chance is to replace other lines by accident, which would be seen in services not starting (diff of postinst looked good in regard to that not happening)

[ Other Info ]

 * We could try to backport changes to dh, but that is way more complex, and would impose much bigger regression risk impacting many other packages as they are rebuilt. Hence I'd avoid that post-release and fix them one by one as proposed here-

----

This has gone through some iterations, and it seems something has broken the variant in Jammy.

Background in bug 1847361

What this does as TL;DR:
- on package upgrade it saves the modules you might later hot-attach in a temporary path
- if a guest was started before upgrade and still runs, it can not load the .so of the current qemu in /usr
- instead it falls back to load them from that temporary path, allowing "guests started before upgrade" to still be able to load drivers
- up to Focal that is tmpfs
- later this changed to a systemd mount unit
- where it is a systemd unit, we use --no-restart-on-upgrade to keep it active
- in both cases the prerm saves the files
- the postrm in remove/purge case cleans
- otherwise it stays until reboot as it is a temporary directory

Now the problem is, it seems on Jammy --no-restart-on-upgrade is ignored.

Focal (no unit yet):
$ apt install -y --reinstall qemu-block-extra
$ ll /var/run/qemu/
total 4
drwxr-xr-x 3 root root 80 Jan 24 17:18 ./
drwxr-xr-x 31 root root 880 Jan 24 17:18 ../
drwxr-xr-x 2 root root 120 Jan 24 17:18 Debian_1_4.2-3ubuntu6.28/
-rw-r--r-- 1 root root 145 Jan 24 17:18 README

=> all good here

Jammy (mount unit, but restarted which it should not be)

root@j-vm:~# apt install -y --reinstall qemu-block-extra; systemctl status run-qemu.mount; ls -laF /run/qemu/
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
0 upgraded, 0 newly installed, 1 reinstalled, 0 to remove and 0 not upgraded.
Need to get 68.1 kB of archives.
After this operation, 0 B of additional disk space will be used.
Get:1 http://archive.ubuntu.com/ubuntu jammy-updates/main amd64 qemu-block-extra amd64 1:6.2+dfsg-2ubuntu6.16 [68.1 kB]
Fetched 68.1 kB in 0s (565 kB/s)
(Reading database ... 72988 files and directories currently installed.)
Preparing to unpack .../qemu-block-extra_1%3a6.2+dfsg-2ubuntu6.16_amd64.deb ...
Unpacking qemu-block-extra (1:6.2+dfsg-2ubuntu6.16) over (1:6.2+dfsg-2ubuntu6.16) ...
Setting up qemu-block-extra (1:6.2+dfsg-2ubuntu6.16) ...
Scanning processes...
Scanning linux images...

Running kernel seems to be up-to-date.

No services need to be restarted.

No containers need to be restarted.

No user sessions are running outdated binaries.

No VM guests are running outdated hypervisor (qemu) binaries on this host.
● run-qemu.mount - Prepare /run/qemu to allow still running qemu binaries of former builds (after package upgrades) to fallback-load modules from there
     Loaded: loaded (/proc/self/mountinfo; enabled; vendor preset: enabled)
     Active: active (mounted) since Wed 2024-01-24 17:18:51 UTC; 2s ago
      Where: /run/qemu
       What: tmpfs
      Tasks: 0 (limit: 1171)
     Memory: 8.0K
        CPU: 1ms
     CGroup: /system.slice/run-qemu.mount

Jan 24 17:18:51 j-vm systemd[1]: run-qemu.mount: Deactivated successfully.
Jan 24 17:18:51 j-vm systemd[1]: Unmounted Prepare /run/qemu to allow still running qemu binaries of former builds (after package upgrades) to fallback-load modules from there.
Jan 24 17:18:51 j-vm systemd[1]: Mounting Prepare /run/qemu to allow still running qemu binaries of former builds (after package upgrades) to fallback-load modules from there...
Jan 24 17:18:51 j-vm systemd[1]: Mounted Prepare /run/qemu to allow still running qemu binaries of former builds (after package upgrades) to fallback-load modules from there.
total 0
drwxr-xr-x 2 root root 40 Jan 24 17:18 ./
drwxr-xr-x 29 root root 840 Jan 24 17:13 ../

=> Broken

Mantic (mount unit, behaving as it should)

root@m-vm:~# apt install -y --reinstall qemu-block-extra; systemctl status run-qemu.mount; ls -laF /run/qemu/
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
0 upgraded, 0 newly installed, 1 reinstalled, 0 to remove and 0 not upgraded.
Need to get 113 kB of archives.
After this operation, 0 B of additional disk space will be used.
Get:1 http://archive.ubuntu.com/ubuntu mantic-updates/main amd64 qemu-block-extra amd64 1:8.0.4+dfsg-1ubuntu3.23.10.2 [113 kB]
Fetched 113 kB in 0s (774 kB/s)
(Reading database ... 67919 files and directories currently installed.)
Preparing to unpack .../qemu-block-extra_1%3a8.0.4+dfsg-1ubuntu3.23.10.2_amd64.deb ...
Unpacking qemu-block-extra (1:8.0.4+dfsg-1ubuntu3.23.10.2) over (1:8.0.4+dfsg-1ubuntu3.23.10.2) ...
Setting up qemu-block-extra (1:8.0.4+dfsg-1ubuntu3.23.10.2) ...
Scanning processes...
Scanning linux images...

Running kernel seems to be up-to-date.

No services need to be restarted.

No containers need to be restarted.

No user sessions are running outdated binaries.

No VM guests are running outdated hypervisor (qemu) binaries on this host.
● run-qemu.mount - Prepare /run/qemu to allow still running qemu binaries of former builds (after package upgrades) to fallback-load modules from there
     Loaded: loaded (/lib/systemd/system/run-qemu.mount; enabled; preset: enabled)
     Active: active (mounted) since Wed 2024-01-24 17:12:40 UTC; 6min ago
      Where: /run/qemu
       What: tmpfs
      Tasks: 0 (limit: 1095)
     Memory: 8.0K
        CPU: 2ms
     CGroup: /system.slice/run-qemu.mount

Jan 24 17:12:40 m-vm systemd[1]: Mounting run-qemu.mount - Prepare /run/qemu to allow still running qemu binaries of former builds (after package upgrades) to fallback-load modules from there...
Jan 24 17:12:40 m-vm systemd[1]: Mounted run-qemu.mount - Prepare /run/qemu to allow still running qemu binaries of former builds (after package upgrades) to fallback-load modules from there.
total 0
drwxr-xr-x 3 root root 60 Jan 24 17:18 ./
drwxr-xr-x 32 root root 900 Jan 24 17:12 ../
drwxr-xr-x 2 root root 180 Jan 24 17:18 Debian_1_8.0.4+dfsg-1ubuntu3.23.10.2/

=> Good

---

reproducing the issue is easy, just run:
  $ apt install -y --reinstall qemu-block-extra
The unit should stay as-is and the modules should be saved in the dir as shown above.

Task: find why this unit is restarted despite --no-restart-on-upgrade and prevent that.

[Christian Ehrhardt  (paelzer)]

Code is similar behavior is not

Jammy:
https://git.launchpad.net/ubuntu/+source/qemu/tree/debian/rules?h=ubuntu/jammy-updates#n179
https://git.launchpad.net/ubuntu/+source/qemu/tree/debian/rules?h=ubuntu/jammy-updates#n432

Mantic:
https://git.launchpad.net/ubuntu/+source/qemu/tree/debian/rules?h=ubuntu/mantic-updates#n295
https://git.launchpad.net/ubuntu/+source/qemu/tree/debian/rules?h=ubuntu/mantic-updates#n475

This might or might not be related to similar issues with .socket units.
That was back in https://bugs.launchpad.net/ubuntu/+source/debhelper/+bug/1959054
This is a huge topic, but a good study on the underlying mechanisms if you follow all the links and discussions from there.

[Christian Ehrhardt  (paelzer)]

It really seems to be dh_installsystemd/13.6ubuntu1

You can quick compare this:
root@j-vm:~# grep mount /var/lib/dpkg/info/qemu-block-extra*
/var/lib/dpkg/info/qemu-block-extra.list:/lib/systemd/system/run-qemu.mount
/var/lib/dpkg/info/qemu-block-extra.md5sums:3cf5dc7461348db7d58b6b99b5878731 lib/systemd/system/run-qemu.mount
/var/lib/dpkg/info/qemu-block-extra.postinst: if deb-systemd-helper debian-installed 'run-qemu.mount'; then
/var/lib/dpkg/info/qemu-block-extra.postinst: deb-systemd-helper unmask 'run-qemu.mount' >/dev/null || true
/var/lib/dpkg/info/qemu-block-extra.postinst: if deb-systemd-helper --quiet was-enabled 'run-qemu.mount'; then
/var/lib/dpkg/info/qemu-block-extra.postinst: deb-systemd-helper enable 'run-qemu.mount' >/dev/null || true
/var/lib/dpkg/info/qemu-block-extra.postinst: deb-systemd-helper update-state 'run-qemu.mount' >/dev/null || true
/var/lib/dpkg/info/qemu-block-extra.postinst: deb-systemd-invoke $_dh_action 'run-qemu.mount' >/dev/null || true
/var/lib/dpkg/info/qemu-block-extra.postinst:# dh_installsystemd will not fully enable or start .mount units, but we want
/var/lib/dpkg/info/qemu-block-extra.postinst: systemctl enable 'run-qemu.mount' >/dev/null || true
/var/lib/dpkg/info/qemu-block-extra.postinst: deb-systemd-invoke start 'run-qemu.mount' >/dev/null || true
/var/lib/dpkg/info/qemu-block-extra.postrm: deb-systemd-helper mask 'run-qemu.mount' >/dev/null || true
/var/lib/dpkg/info/qemu-block-extra.postrm: deb-systemd-helper purge 'run-qemu.mount' >/dev/null || true
/var/lib/dpkg/info/qemu-block-extra.postrm: deb-systemd-helper unmask 'run-qemu.mount' >/dev/null || true
/var/lib/dpkg/info/qemu-block-extra.postrm:case $1 in (purge) if systemctl is-active -q run-qemu.mount; then systemctl stop run-qemu.mount || true; fi; rm -rf "/run/qemu";; esac
/var/lib/dpkg/info/qemu-block-extra.prerm: deb-systemd-invoke stop 'run-qemu.mount' >/dev/null || true

root@m-vm:~# grep mount /var/lib/dpkg/info/qemu-block-extra*
/var/lib/dpkg/info/qemu-block-extra.list:/lib/systemd/system/run-qemu.mount
/var/lib/dpkg/info/qemu-block-extra.md5sums:3cf5dc7461348db7d58b6b99b5878731 lib/systemd/system/run-qemu.mount
/var/lib/dpkg/info/qemu-block-extra.postinst:# dh_installsystemd will not fully enable or start .mount units, but we want
/var/lib/dpkg/info/qemu-block-extra.postinst: systemctl enable 'run-qemu.mount' >/dev/null || true
/var/lib/dpkg/info/qemu-block-extra.postinst: deb-systemd-invoke start 'run-qemu.mount' >/dev/null || true
/var/lib/dpkg/info/qemu-block-extra.postrm:case $1 in (purge) if systemctl is-active -q run-qemu.mount; then systemctl stop run-qemu.mount || true; fi; rm -rf "/run/qemu";; esac

The criticial bit is this line:
/var/lib/dpkg/info/qemu-block-extra.postinst:63: deb-systemd-invoke $_dh_action 'run-qemu.mount' >/dev/null || true

This is the full section:
# End automatically added section
# Automatically added by dh_installsystemd/13.6ubuntu1
if [ "$1" = "configure" ] || [ "$1" = "abort-upgrade" ] || [ "$1" = "abort-deconfigure" ] || [ "$1" = "abort-remove" ] ; then
        if [ -d /run/systemd/system ]; then
  ...

[Christian Ehrhardt  (paelzer)]

A first shot at a fix is building in a PPA [1] now, ...

TODO from here:
- wait for the build
- test install
- test reinstall
- test upgrade to jammy
- test upgrade from jammy
- Propose MR for team review

[1]: https://launchpad.net/~paelzer/+archive/ubuntu/lp-2051153-fix-run-qemu-mount-restart

[Christian Ehrhardt  (paelzer)]

Wow, dh_installsystemd is insisting to handle it wrong in this case :-)

Start: calling dh_installsystemd for run-qemu.mount with --no-restart-on-upgrade
  => Ignores --no-restart-on-upgrade and restarts the unit each upgrade

Fix 1: Not calling dh_installsystemd for run-qemu.mount
  => picks up the unit with defaults and restarts the unit each upgrade

Fix 2: Calling dh_installsystemd for run-qemu.mount but with --no-start --no-enable
  => ignores --no-start and restarts the unit each upgrade

Fix 3: Calling dh_installsystemd with --exclude=run-qemu.mount
  => ignores --exclude and restarts the unit each upgrade

At this point I stripped qemu down to not do the binary builds, just wrap the maintscripts.
That allows to iterate quickly and it confirmed (in a minute each) that --exclude, --no-start and --no-restart-on-upgrade all are placing the restart on upgrade rule.

Fix 4: Modify the postinst after dh_installdeb
  => Currently building ...

[Christian Ehrhardt  (paelzer)]

Ok this works even in a full build

root@j-vm:~# apt install -y --reinstall qemu-block-extra; systemctl status run-qemu.mount; ls -laF /run/qemu/
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
The following additional packages will be installed:
  qemu-system-common qemu-system-data qemu-system-gui qemu-system-x86 qemu-utils
Suggested packages:
  samba vde2 debootstrap
The following packages will be upgraded:
  qemu-block-extra qemu-system-common qemu-system-data qemu-system-gui qemu-system-x86 qemu-utils
6 upgraded, 0 newly installed, 0 to remove and 4 not upgraded.
Need to get 16.0 MB of archives.
After this operation, 1024 B disk space will be freed.
Get:1 https://ppa.launchpadcontent.net/paelzer/lp-2051153-fix-run-qemu-mount-restart/ubuntu jammy/main amd64 qemu-system-gui amd64 1:6.2+dfsg-2ubuntu6.17~jammyppa19 [325 kB]
Get:2 https://ppa.launchpadcontent.net/paelzer/lp-2051153-fix-run-qemu-mount-restart/ubuntu jammy/main amd64 qemu-block-extra amd64 1:6.2+dfsg-2ubuntu6.17~jammyppa19 [169 kB]
Get:3 https://ppa.launchpadcontent.net/paelzer/lp-2051153-fix-run-qemu-mount-restart/ubuntu jammy/main amd64 qemu-system-x86 amd64 1:6.2+dfsg-2ubuntu6.17~jammyppa19 [10.2 MB]
Get:4 https://ppa.launchpadcontent.net/paelzer/lp-2051153-fix-run-qemu-mount-restart/ubuntu jammy/main amd64 qemu-system-common amd64 1:6.2+dfsg-2ubuntu6.17~jammyppa19 [2147 kB]
Get:5 https://ppa.launchpadcontent.net/paelzer/lp-2051153-fix-run-qemu-mount-restart/ubuntu jammy/main amd64 qemu-utils amd64 1:6.2+dfsg-2ubuntu6.17~jammyppa19 [1624 kB]
Get:6 https://ppa.launchpadcontent.net/paelzer/lp-2051153-fix-run-qemu-mount-restart/ubuntu jammy/main amd64 qemu-system-data all 1:6.2+dfsg-2ubuntu6.17~jammyppa19 [1527 kB]
Fetched 16.0 MB in 18s (889 kB/s)
(Reading database ... 95002 files and directories currently installed.)
Preparing to unpack .../0-qemu-system-gui_1%3a6.2+dfsg-2ubuntu6.17~jammyppa19_amd64.deb ...
Unpacking qemu-system-gui (1:6.2+dfsg-2ubuntu6.17~jammyppa19) over (1:6.2+dfsg-2ubuntu6.17~jammyppa3) ...
Preparing to unpack .../1-qemu-block-extra_1%3a6.2+dfsg-2ubuntu6.17~jammyppa19_amd64.deb ...
Unpacking qemu-block-extra (1:6.2+dfsg-2ubuntu6.17~jammyppa19) over (1:6.2+dfsg-2ubuntu6.17~jammyppa3) ...
Preparing to unpack .../2-qemu-system-x86_1%3a6.2+dfsg-2ubuntu6.17~jammyppa19_amd64.deb ...
Unpacking qemu-system-x86 (1:6.2+dfsg-2ubuntu6.17~jammyppa19) over (1:6.2+dfsg-2ubuntu6.17~jammyppa3) ...
Preparing to unpack .../3-qemu-system-common_1%3a6.2+dfsg-2ubuntu6.17~jammyppa19_amd64.deb ...
Unpacking qemu-system-common (1:6.2+dfsg-2ubuntu6.17~jammyppa19) over (1:6.2+dfsg-2ubuntu6.17~jammyppa3) ...
Preparing to unpack .../4-qemu-utils_1%3a6.2+dfsg-2ubuntu6.17~jammyppa19_amd64.deb ...
Unpacking qemu-utils (1:6.2+dfsg-2ubuntu6.17~jammyppa19) over (1:6.2+dfsg-2ubuntu6.17~jammyppa3) ...
Preparing to unpack .../5-qemu-system-data_1%3a6.2+d...

[Christian Ehrhardt  (paelzer)]

Upplaoded to -unapproved for SRU review

[Timo Aaltonen (tjaalton)]

Hello Christian, or anyone else affected,

Accepted qemu into jammy-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/qemu/1:6.2+dfsg-2ubuntu6.17 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, what testing has been performed on the package and change the tag from verification-needed-jammy to verification-done-jammy. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-jammy. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

[Christian Ehrhardt  (paelzer)]

Verification:

1. check old behavior. I did so twice with a sleep in between to show that it resets the unit and the time

root@j-vm:~# apt-cache policy qemu-block-extra; apt install -y --reinstall qemu-block-extra; systemctl status run-qemu.mount; ls -laF /run/qemu/
qemu-block-extra:
  Installed: 1:6.2+dfsg-2ubuntu6.16
  Candidate: 1:6.2+dfsg-2ubuntu6.16
  Version table:
 *** 1:6.2+dfsg-2ubuntu6.16 500
        500 http://archive.ubuntu.com/ubuntu jammy-updates/main amd64 Packages
        500 http://security.ubuntu.com/ubuntu jammy-security/main amd64 Packages
        100 /var/lib/dpkg/status
     1:6.2+dfsg-2ubuntu6 500
        500 http://archive.ubuntu.com/ubuntu jammy/main amd64 Packages
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
0 upgraded, 0 newly installed, 1 reinstalled, 0 to remove and 0 not upgraded.
Need to get 68.1 kB of archives.
After this operation, 0 B of additional disk space will be used.
Get:1 http://archive.ubuntu.com/ubuntu jammy-updates/main amd64 qemu-block-extra amd64 1:6.2+dfsg-2ubuntu6.16 [68.1 kB]
Fetched 68.1 kB in 0s (460 kB/s)
(Reading database ... 72988 files and directories currently installed.)
Preparing to unpack .../qemu-block-extra_1%3a6.2+dfsg-2ubuntu6.16_amd64.deb ...
Unpacking qemu-block-extra (1:6.2+dfsg-2ubuntu6.16) over (1:6.2+dfsg-2ubuntu6.16) ...
Setting up qemu-block-extra (1:6.2+dfsg-2ubuntu6.16) ...
Scanning processes...
Scanning linux images...

Running kernel seems to be up-to-date.

No services need to be restarted.

No containers need to be restarted.

No user sessions are running outdated binaries.

No VM guests are running outdated hypervisor (qemu) binaries on this host.
● run-qemu.mount - Prepare /run/qemu to allow still running qemu binaries of former builds (after package upgrades) to fallback-load modules from there
     Loaded: loaded (/proc/self/mountinfo; enabled; vendor preset: enabled)
     Active: active (mounted) since Mon 2024-02-05 10:39:27 UTC; 2s ago
      Where: /run/qemu
       What: tmpfs
      Tasks: 0 (limit: 1171)
     Memory: 8.0K
        CPU: 2ms
     CGroup: /system.slice/run-qemu.mount

Feb 05 10:39:27 j-vm systemd[1]: Mounting Prepare /run/qemu to allow still running qemu binaries of former builds (after package upgrades) to fallback-load modules from there...
Feb 05 10:39:27 j-vm systemd[1]: Mounted Prepare /run/qemu to allow still running qemu binaries of former builds (after package upgrades) to fallback-load modules from there.
total 0
drwxr-xr-x 2 root root 40 Feb 5 10:39 ./
drwxr-xr-x 29 root root 840 Feb 5 10:38 ../
root@j-vm:~#
root@j-vm:~# sleep 10s
root@j-vm:~# apt-cache policy qemu-block-extra; apt install -y --reinstall qemu-block-extra; systemctl status run-qemu.mount; ls -laF /run/qemu/
qemu-block-extra:
  Instal...

[Christian Ehrhardt  (paelzer)]

Verification part II:
upgrade to proposed, then also re-install (to showcase future updates)
You can see that this update not only finally works, but also correctly backs up the former version (there is nothing we can do for former former versions).

root@j-vm:~# apt-cache policy qemu-block-extra; apt install -y --reinstall qemu-block-extra; systemctl status run-qemu.mount; ls -laF /run/qemu/
qemu-block-extra:
  Installed: 1:6.2+dfsg-2ubuntu6.16
  Candidate: 1:6.2+dfsg-2ubuntu6.17
  Version table:
     1:6.2+dfsg-2ubuntu6.17 500
        500 http://archive.ubuntu.com/ubuntu jammy-proposed/main amd64 Packages
 *** 1:6.2+dfsg-2ubuntu6.16 500
        500 http://archive.ubuntu.com/ubuntu jammy-updates/main amd64 Packages
        500 http://security.ubuntu.com/ubuntu jammy-security/main amd64 Packages
        100 /var/lib/dpkg/status
     1:6.2+dfsg-2ubuntu6 500
        500 http://archive.ubuntu.com/ubuntu jammy/main amd64 Packages
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
The following additional packages will be installed:
  qemu-system-common qemu-system-data qemu-system-gui qemu-system-x86 qemu-utils
Suggested packages:
  samba vde2 debootstrap
The following packages will be upgraded:
  qemu-block-extra qemu-system-common qemu-system-data qemu-system-gui qemu-system-x86 qemu-utils
6 upgraded, 0 newly installed, 0 to remove and 40 not upgraded.
Need to get 15.4 MB of archives.
After this operation, 5120 B of additional disk space will be used.
Get:1 http://archive.ubuntu.com/ubuntu jammy-proposed/main amd64 qemu-system-gui amd64 1:6.2+dfsg-2ubuntu6.17 [220 kB]
Get:2 http://archive.ubuntu.com/ubuntu jammy-proposed/main amd64 qemu-block-extra amd64 1:6.2+dfsg-2ubuntu6.17 [68.1 kB]
Get:3 http://archive.ubuntu.com/ubuntu jammy-proposed/main amd64 qemu-system-x86 amd64 1:6.2+dfsg-2ubuntu6.17 [10.1 MB]
Get:4 http://archive.ubuntu.com/ubuntu jammy-proposed/main amd64 qemu-system-common amd64 1:6.2+dfsg-2ubuntu6.17 [2047 kB]
Get:5 http://archive.ubuntu.com/ubuntu jammy-proposed/main amd64 qemu-utils amd64 1:6.2+dfsg-2ubuntu6.17 [1525 kB]
Get:6 http://archive.ubuntu.com/ubuntu jammy-proposed/main amd64 qemu-system-data all 1:6.2+dfsg-2ubuntu6.17 [1431 kB]
Fetched 15.4 MB in 3s (5868 kB/s)
(Reading database ... 72988 files and directories currently installed.)
Preparing to unpack .../0-qemu-system-gui_1%3a6.2+dfsg-2ubuntu6.17_amd64.deb ...
Unpacking qemu-system-gui (1:6.2+dfsg-2ubuntu6.17) over (1:6.2+dfsg-2ubuntu6.16) ...
Preparing to unpack .../1-qemu-block-extra_1%3a6.2+dfsg-2ubuntu6.17_amd64.deb ...
Unpacking qemu-block-extra (1:6.2+dfsg-2ubuntu6.17) over (1:6.2+dfsg-2ubuntu6.16) ...
Preparing to unpack .../2-qemu-system-x86_1%3a6.2+dfsg-2ubuntu6.17_amd64.deb ...
Unpacking qemu-system-x86 (1:6.2+dfsg-2ubuntu6.17) over (1:6.2+dfsg-2ubuntu6.16) ...
Preparing to unpack .../3-qemu-system-common_1%3a6.2+dfsg-2ubuntu6.17_amd64.deb ...
Unpacking qemu-system-common (1:6.2+dfsg-2ubuntu6.17) over (1:6.2+dfsg-2ubuntu6.16) ...
Preparing to unpack .../4-qemu-utils_1%3a6.2+dfsg-2ubuntu6.17_amd64.deb ...
Unpacking qemu-utils (1:6.2+dfsg-2ubuntu6.17) over (1:6.2+dfsg-2ubuntu6.16) ...
Preparing to unpack ......

[Christian Ehrhardt  (paelzer)]

Just to be sure I checked removal (things should go away) and fresh install (unit should be started but empty as there is nothing from before to back up).

# removal

root@j-vm:~# apt remove -y qemu-block-extra; systemctl status run-qemu.mount; ls -laF /run/qemu/
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
The following packages were automatically installed and are no longer required:
  adwaita-icon-theme alsa-topology-conf alsa-ucm-conf at-spi2-core cpu-checker dconf-gsettings-backend dconf-service fontconfig fontconfig-config fonts-dejavu-core glib-networking glib-networking-common
  glib-networking-services gsettings-desktop-schemas gstreamer1.0-plugins-base gstreamer1.0-plugins-good gstreamer1.0-x gtk-update-icon-cache hicolor-icon-theme humanity-icon-theme ibverbs-providers ipxe-qemu
  ipxe-qemu-256k-compat-efi-roms libaa1 libasound2 libasound2-data libasyncns0 libatk-bridge2.0-0 libatk1.0-0 libatk1.0-data libatspi2.0-0 libavahi-client3 libavahi-common-data libavahi-common3 libavc1394-0
  libboost-iostreams1.74.0 libboost-thread1.74.0 libbrlapi0.8 libcaca0 libcacard0 libcairo-gobject2 libcairo2 libcdparanoia0 libcolord2 libcups2 libdatrie1 libdaxctl1 libdconf1 libdecor-0-0
  libdecor-0-plugin-1-cairo libdeflate0 libdrm-amdgpu1 libdrm-intel1 libdrm-nouveau2 libdrm-radeon1 libdv4 libepoxy0 libfdt1 libflac8 libfontconfig1 libgbm1 libgdk-pixbuf-2.0-0 libgdk-pixbuf2.0-bin
  libgdk-pixbuf2.0-common libgfapi0 libgfrpc0 libgfxdr0 libgl1 libgl1-amber-dri libgl1-mesa-dri libglapi-mesa libglusterfs0 libglvnd0 libglx-mesa0 libglx0 libgraphite2-3 libgstreamer-plugins-base1.0-0
  libgstreamer-plugins-good1.0-0 libgtk-3-0 libgtk-3-bin libgtk-3-common libharfbuzz0b libibverbs1 libiec61883-0 libiscsi7 libjack-jackd2-0 libjbig0 libjpeg-turbo8 libjpeg8 liblcms2-2 libllvm15 libmp3lame0
  libmpg123-0 libndctl6 libnl-route-3-200 libogg0 libopus0 liborc-0.4-0 libpango-1.0-0 libpangocairo-1.0-0 libpangoft2-1.0-0 libpciaccess0 libpcsclite1 libpixman-1-0 libpmem1 libpmemobj1 libproxy1v5 libpulse0
  librados2 libraw1394-11 librbd1 librdmacm1 librsvg2-2 librsvg2-common libsamplerate0 libsdl2-2.0-0 libsensors-config libsensors5 libshout3 libslirp0 libsndfile1 libsoup2.4-1 libsoup2.4-common libspeex1
  libspice-server1 libtag1v5 libtag1v5-vanilla libthai-data libthai0 libtheora0 libtiff5 libtwolame0 liburing2 libusbredirparser1 libv4l-0 libv4lconvert0 libvirglrenderer1 libvisual-0.4-0 libvorbis0a
  libvorbisenc2 libvpx7 libvte-2.91-0 libvte-2.91-common libwavpack1 libwayland-client0 libwayland-cursor0 libwayland-egl1 libwayland-server0 libwebp7 libx11-xcb1 libxcb-dri2-0 libxcb-dri3-0 libxcb-glx0
  libxcb-present0 libxcb-randr0 libxcb-render0 libxcb-shm0 libxcb-sync1 libxcb-xfixes0 libxcomposite1 libxcursor1 libxdamage1 libxfixes3 libxi6 libxinerama1 libxkbcommon0 libxrandr2 libxrender1 libxshmfence1
  libxss1 libxtst6 libxv1 libxxf86vm1 msr-tools ovmf qemu-system-common qemu-system-data qemu-system-gui qemu-system-x86 qemu-utils seabios session-migration ubuntu-mono x11-common
Use 'apt autoremove' to remove them.
The following packages will be REMOVED:
  qemu-block-extra
0 upgraded, 0 newly installed, 1 to remove a...

[Robie Basak (racb)]

This is blocked by a livecd-rootfs autopkgtest failure on Jammy. It passed yesterday on a different package. I've retried it to see if it's spurious.

[Andreas Hasenack (ahasenack)]

The test passed now

[Andreas Hasenack (ahasenack)]

The verification of the Stable Release Update for qemu has completed successfully and the package is now being released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.

[Launchpad Janitor (janitor)]

This bug was fixed in the package qemu - 1:6.2+dfsg-2ubuntu6.17

---------------
qemu (1:6.2+dfsg-2ubuntu6.17) jammy; urgency=medium

  * d/rules: modify qemu-block-extra postinst to avoid
    restarting run-qemu.mount (LP: #2051153)

 -- Christian Ehrhardt <email address hidden> Mon, 29 Jan 2024 11:43:30 +0100