LL 5.4 - New Install - Error : Diskfilter writes not supported

[CP_ PDN]

Follow Up ( Based on https://askubuntu.com/questions/468466/d...this-error )

For a temporary fix for this problem :
    Edit :/etc/grub.d/10_linux
    Replace 'quick_boot="1"' with 'quick_boot="0"'

    Then :
    sudo update-grub

But just wondering, if the LVM / RAID part is buggy, why would the installer provide this option if this is a long standing  bug ?
Or nothing can be done as this is the standard installer from Ubuntu and LL is waiting for an upstream fix?