Comment 9 for bug 1969365

In the VM created in my above comment, I enabled proposed, installed the new systemd and rebooted. After that, I re-ran:

cd /boot
sudo kexec -l vmlinuz --initrd initrd.img --append 'BOOT_IMAGE=/boot/vmlinuz-5.4.0-167-generic root=LABEL=cloudimg-rootfs ro console=tty1 console=ttyS0'
sudo reboot

And observed the following in the console:

[ OK ] Reached target Final Step.
         Starting Reboot via kexec...
[ 102.782246] systemd-udevd[369]: anon_vma(937:udisks2.service): Worker [960] did not accept message, killing the worker: Connection refused
[ 102.784224] systemd-udevd[369]: anon_vma(937:udisks2.service): Worker [963] did not accept message, killing the worker: Connection refused
[ 102.786398] systemd-udevd[369]: anon_vma(937:udisks2.service): Worker [966] did not accept message, killing the worker: Connection refused
[ 102.788390] systemd-udevd[369]: anon_vma(937:udisks2.service): Worker [968] did not accept message, killing the worker: Connection refused
[ 102.789954] systemd-udevd[369]: anon_vma(937:udisks2.service): Worker [962] did not accept message, killing the worker: Connection refused
[ 102.791562] systemd-udevd[369]: anon_vma(937:udisks2.service): Worker [961] did not accept message, killing the worker: Connection refused
[ 102.793198] systemd-udevd[369]: anon_vma(937:udisks2.service): Worker [964] did not accept message, killing the worker: Connection refused
[ 102.794669] systemd-udevd[369]: anon_vma(937:udisks2.service): Worker [967] did not accept message, killing the worker: Connection refused
[ 102.796841] systemd-udevd[369]: anon_vma(937:udisks2.service): Worker [965] did not accept message, killing the worker: Connection refused
[ 102.904092] kexec_core: Starting new kernel
[ 0.000000] Linux version 5.4.0-167-generic (buildd@lcy02-amd64-010) (gcc version 9.4.0 (Ubuntu 9.4.0-1ubuntu1~20.04.2)) #184-Ubuntu SMP Tue Oct 31 09:21:49 UTC 2023 (Ubuntu 5.4.0-167.184-generic 5.4.252)

So I can confirm that the new systemd addresses this bug.