The encryption wiki
(https://en.opensuse.org/Portal:Aeon/Encryption#Default_Mode) states that the
kernel cmdline is measured in the decryption phase, but I'm not sure this is
actually happening.

If I do the following:
1. Reboot
2. Press <space> to bring up sdboot
3. Edit the cmdline (eg. remove the quiet parameter or smth harmless)
4. continue to boot

I don't get asked for my recovery key, which I should if the following line of
the wiki is correct "Kernel and initrd (including kernel cmdline parameters)".
In /etc/sysconfig/fde-tools I see that the used PCR registers are
FDE_SEAL_PCR_LIST=0,4,5,7,9. 

The question is then what is measured in PCR 9, which in grub-land includes all
kernel related things
(https://uapi-group.org/specifications/specs/linux_tpm_pcr_registry/). It is
noted there that sdboot measures the cmdline into PCR 12.

I can confirm that PCR 12 is the cmdline by running
/usr/lib/systemd/systemd-pcrlock:  

12 █ kernel-config      ipl                               ✓
be123ca906a997b2b373ef03d7d085ad9694d91f7fb03f04cc49852b0c093c1a F   -         
                       String:
initrd=\aeon\6.10.9-1-default\initrd-4e08a4db634c2b8bda0cb5a8673...

But there it states that PCR 9 includes the following:
9 █ kernel-initrd      event-tag                         -
be123ca906a997b2b373ef03d7d085ad9694d91f7fb03f04cc49852b0c093c1a F  
710-kernel-cmdline-initrd-entry   Linux: kernel command line
9 █ kernel-initrd      event-tag                         -
fc402f2e93e4e4b56348e471f18de5acd3f60f5b0dac22adb25da65e8d8e936d F  
710-kernel-cmdline-initrd-entry   Linux: initrd
which indicates that the cmdline is measured, but that doesn't explain why I
can boot.

I verified that the base setup is working by disabling secure boot, which
triggered the recovery screen. 

Could someone verify, which registers are used and what they should exactly
measure, because either my setup is broken (possible) or sdboot doesn't use PCR
9 in the way indicated by the wiki?