--print-cmdline with btrfs roots spits back a bunch of redundant subvolume info

[cmurf]

[chris@f25h ~]$ sudo dracut --print-cmdline
rd.lvm.lv=vg/swap
resume=/dev/mapper/vg-swap root=PARTUUID=b9f0e09b-c6cf-4f48-8511-e63e3ec26f1f rootfstype=btrfs rootflags=rw,relatime,seclabel,ssd,space_cache,subvolid=257,subvol=/root,subvol=root

All of the listed rootflags options are unnecessary except subvol=root (or subvol=/root or subvolid=257), not all three are needed. And the other options are defaults so I don't know why they're being recommended by print-cmdline.

[haraldh]

you are right. it's a combination of

$ findmnt -e -v -n -o OPTIONS --target /
rw,relatime,ssd,space_cache,subvolid=491,subvol=/root:test:master

and

$ findmnt -e -v -n -o FSROOT --target /
/root:test:master

adding the info of FSROOT should be omitted if already present.

The subvolid seems to be redundant too in /proc/self/mountinfo:

$ fgrep test:master /proc/self/mountinfo 
62 0 0:37 /root:test:master / rw,relatime shared:1 - btrfs /dev/sda3 rw,ssd,space_cache,subvolid=491,subvol=/root:test:master