Comment # 16 on bug 1047225 from Takashi Iwai

(In reply to Stefan Dirsch from comment #15)
> Seems I've tested something stupid. I've made a clean full-encrypted LVM
> installation and now the combination
> 
>   omit_dracutmodules+="plymouth"
> 
> for initrd creation and
> 
>   splash=silent
> 
> as kernel command line parameter works for me. I've been asked for a
> password for the encrypted LVM partition setup.

This can be a difference between the encryption of the root fs and of the home
directory, too.  When a home directory is encrypted while the root fs isn't,
the decrpyto password is asked after initrd, thus the system thinks it's done
via plymouth.