What were you trying to do that didn't work?

A customer has a disk layout where slash is on standard partition and swap on LVM partition:

# lsblk
NAME          MAJ:MIN RM  SIZE RO TYPE MOUNTPOINTS
sr0            11:0    1 1024M  0 rom  
vda           252:0    0   20G  0 disk 
├─vda1        252:1    0    1G  0 part /boot
├─vda2        252:2    0    2G  0 part 
│ └─rhel-swap 253:0    0    2G  0 lvm  [SWAP]
└─vda3        252:3    0   10G  0 part /

# cat /proc/cmdline 
[...] resume=/dev/mapper/rhel-swap rd.lvm.lv=rhel/swap

Upgrading the system from 8 to 9 (and probably 9 to 10 but didn't test) fails after the system was upgraded, because the initramfs waits on resume=/dev/mapper/rhel-swap which becomes never available, because the dracut module lvm is not embedded in the initramfs built while upgrading the kernel.
The reason is because leapp executes the upgrade after doing mount -a, which doesn't mount the swap, see RHEL-119786.
Due to not mounting the swap, dracut will not embed the lvm module, because of RHEL-119785.

IMHO the only solution for now is to include swapon in the initramfs and perform a mount -a; swapon -a before executing the upgrade script.
Unfortunately apparently there may be some issues with aarch64, as per comments in /usr/share/leapp-repository/repositories/system_upgrade/common/actors/commonleappdracutmodules/files/dracut/85sys-upgrade-redhat/do-upgrade.sh.

EDIT: using swapon -a doesn't work probably because we are in a container:

[   50.380415] upgrade[807]: swapon: /dev/mapper/rhel-swap: swapon failed: Operation not permitted

Workaround: create a dracut drop-in to add the device:

# echo "add_device+=\" $(grep -oP "resume=\K([^ ]*)" /proc/cmdline) \"" > /etc/dracut.conf.d/resume.conf

What is the impact of this issue to you?

Can't reboot on upgraded kernel without manually removing resume=xxx then rebuilding the initramfs after first boot.

Please provide the package NVR for which the bug is seen:

leapp-upgrade-el8toel9-0.22.0-1.el8_10.noarch

How reproducible is this bug?:

Always

Steps to reproduce

1. Install a RHEL8 system with slash on standard partition and swap on LVM
2. Upgrade it

Expected results

Boots fine on upgraded kernel

Actual results

Hangs forever on upgraded kernel on "resume" module