Arch Linux

Description:
It appears that [pam] can't handle password hashes generated using the default crypt(3) method (yescrypt). This is problematic when using tools that generate settings based on those defaults and don't hardcode a known working hash (for example sha512) such as [shadow] does currently in /etc/pam.d/.

Additional info:
* package versions:
* pam 1.4.0-3
* libxcrypt 4.4.17-1
* shadow 4.8.1-4
* systemd 246.6-1
* glibc 2.32-5

Steps to reproduce:
The problem originally manifested itself in that that I wasn't able to log in as root user after setting the password using `systemd-firstboot --force --root-password=`. In the following I've set the root password and subsequently tried to change to root using `su