I had this situationsda four partitionsda1 bios boot 32msda2 ext4 boot 500Msda3 swapsda4 luks+btrfsI use this initrdmkinitrd -c -k `ls /var/log/packages/kernel-generic-* |cut -d - -f 3` -f btrfs -l it -r /dev/mapper/lukssda4 -m ext4:btrfs:generic-hid:hid-generic:ehci-hcd:ohci-hcd:uhci-hcd -h /dev/sda3 -u -B -R -L -C /dev/sda4This is fstabLABEL=SWAP      swap             swap        defaults         0   0/dev/mapper/lukssda4    /                btrfs       defaults,ssd     1   1/dev/sda2           /boot            ext4        defaults         1   2/dev/mapper/lukssda4    /home            btrfs       defaults,subvolid=272,ssd  0   0devpts              /dev/pts         devpts      gid=5,mode=620   0   0proc                /proc            proc        defaults         0   0tmpfs               /dev/shm         tmpfs       defaults         0   0#tmp directory for vdr-osd teletexttmpfs            /tmp/vtx         tmpfs       size=64m         0   0I did mkinitrd and then grub-mkconfigOn boot it cannot mount the /mnt and saidmnt not present on fstabI have to mount manually /dev/mapper/lukssda4 /mnton every reboot!Why?This is the default grubGRUB_DEFAULT=0#GRUB_HIDDEN_TIMEOUT=0GRUB_HIDDEN_TIMEOUT_QUIET=falseGRUB_TIMEOUT=10GRUB_DISTRIBUTOR=$( sed 's/Slackware /Slackware-/' /etc/slackware-version )GRUB_ENABLE_CRYPTODISK=yGRUB_CMDLINE_LINUX_DEFAULT=resume=/dev/sda3GRUB_CMDLINE_LINUX=cryptdevice=UUID=db2338e0-77be-43dc-b493-e2078418fadf:lukssda4# Uncomment to disable graphical terminal (grub-pc only)#GRUB_TERMINAL=console# The resolution used on graphical terminal# note that you can use only modes which your graphic card supports via VBE# you can see them in real GRUB with the command `vbeinfo'#GRUB_GFXMODE=640x480GRUB_GFXMODE=1024x768x32# Font used on the graphical terminal:GRUB_FONT=/usr/share/grub/dejavusansmono.pf2# Uncomment if you don't want GRUB to pass root=UUID=xxx parameter to Linux#GRUB_DISABLE_LINUX_UUID=true# Uncomment to disable generation of recovery mode menu entrys#GRUB_DISABLE_LINUX_RECOVERY=true
slackware,btrfs and mkinitrd
btrfs;slackware;mkinitrd