Comment # 2 on bug 926331 from Thomas Blume

(In reply to Bernhard Wiedemann from comment #1)
> I guess you dont get the emergency shell from the initrd
> because it is already past that point?

Hm, if the mount service that applies the fstab options (inclusive rw) for
/sysroot fails, the boot process stops in the initrd and you should get the
emergency shell.

> I remember the old "single" mode with sulogin
> coming up in the old days in such a case.

This is equivalent to the rescue.target in systemd.
But this is after switch root and system root is already rw at this stage.