> I am new to syslinux/extlinux. Can I boot from a linux btrfs subvolume? See: syslinux.org/wiki/index.php?title=Filesystem#Btrfs Please note that you need at least 6.04-pre1. Unfortunately, 6.04-pre2 and 6.04-pre3 are not helpful for troubleshooting; avoid them. Hopefully the above helps in some way(?). Regards, Ady.