не для любой. бтрфс или ехт4 таких костылей не требует
$ cp /boot/initrd.img-6.12.38+deb13-amd64 ./initrd.img
$ unmkinitramfs ./initrd.img ./
$ grep btrfs ./ -IR
./main/lib/udev/rules.d/64-btrfs.rules:SUBSYSTEM!="block", GOTO="btrfs_end"
./main/lib/udev/rules.d/64-btrfs.rules:ACTION=="remove", GOTO="btrfs_end"
./main/lib/udev/rules.d/64-btrfs.rules:ENV{ID_FS_TYPE}!="btrfs", GOTO="btrfs_end"
./main/lib/udev/rules.d/64-btrfs.rules:ENV{SYSTEMD_READY}=="0", GOTO="btrfs_end"
./main/lib/udev/rules.d/64-btrfs.rules:# let the kernel know about this btrfs filesystem, and check if it is complete
./main/lib/udev/rules.d/64-btrfs.rules:IMPORT{builtin}="btrfs ready $devnode"
./main/lib/udev/rules.d/64-btrfs.rules:LABEL="btrfs_end"
./main/lib/udev/rules.d/64-btrfs-dm.rules:SUBSYSTEM!="block", GOTO="btrfs_end"
./main/lib/udev/rules.d/64-btrfs-dm.rules:KERNEL!="dm-[0-9]*", GOTO="btrfs_end"
./main/lib/udev/rules.d/64-btrfs-dm.rules:ACTION!="add|change", GOTO="btrfs_end"
./main/lib/udev/rules.d/64-btrfs-dm.rules:ENV{ID_FS_TYPE}!="btrfs", GOTO="btrfs_end"
./main/lib/udev/rules.d/64-btrfs-dm.rules:# Once the device mapper symlink is created, tell btrfs about it
./main/lib/udev/rules.d/64-btrfs-dm.rules:ENV{DM_NAME}=="?*", RUN{builtin}+="btrfs ready /dev/mapper/$env{DM_NAME}"
./main/lib/udev/rules.d/64-btrfs-dm.rules:LABEL="btrfs_end"
./main/lib/udev/rules.d/50-udev-default.rules:KERNEL=="btrfs-control", GROUP="disk"
./main/lib/modules/6.12.38+deb13-amd64/modules.softdep:softdep btrfs pre: blake2b-256
./main/lib/modules/6.12.38+deb13-amd64/modules.softdep:softdep btrfs pre: sha256
./main/lib/modules/6.12.38+deb13-amd64/modules.softdep:softdep btrfs pre: xxhash64
./main/lib/modules/6.12.38+deb13-amd64/modules.softdep:softdep btrfs pre: crypto-crc32c
./main/lib/modules/6.12.38+deb13-amd64/modules.order:kernel/fs/btrfs/btrfs.ko
./main/lib/modules/6.12.38+deb13-amd64/modules.devname:btrfs btrfs-control c10:234
./main/lib/modules/6.12.38+deb13-amd64/modules.dep:kernel/fs/btrfs/btrfs.ko.xz: kernel/crypto/xor.ko.xz kernel/lib/raid6/raid6_pq.ko.xz kernel/lib/libcrc32c.ko.xz
./main/lib/modules/6.12.38+deb13-amd64/modules.alias:alias devname:btrfs-control btrfs
./main/lib/modules/6.12.38+deb13-amd64/modules.alias:alias char-major-10-234 btrfs
./main/lib/modules/6.12.38+deb13-amd64/modules.alias:alias fs-btrfs btrfs
./main/scripts/local-premount/btrfs:if [ -x /bin/btrfs ]
./main/scripts/local-premount/btrfs: modprobe btrfs ||:
./main/scripts/local-premount/btrfs: /bin/btrfs device scan
./main/scripts/local-premount/ORDER:/scripts/local-premount/btrfs "$@"
./main/usr/lib/udev/rules.d/64-btrfs.rules:SUBSYSTEM!="block", GOTO="btrfs_end"
./main/usr/lib/udev/rules.d/64-btrfs.rules:ACTION=="remove", GOTO="btrfs_end"
./main/usr/lib/udev/rules.d/64-btrfs.rules:ENV{ID_FS_TYPE}!="btrfs", GOTO="btrfs_end"
./main/usr/lib/udev/rules.d/64-btrfs.rules:ENV{SYSTEMD_READY}=="0", GOTO="btrfs_end"
./main/usr/lib/udev/rules.d/64-btrfs.rules:# let the kernel know about this btrfs filesystem, and check if it is complete
./main/usr/lib/udev/rules.d/64-btrfs.rules:IMPORT{builtin}="btrfs ready $devnode"
./main/usr/lib/udev/rules.d/64-btrfs.rules:LABEL="btrfs_end"
./main/usr/lib/udev/rules.d/64-btrfs-dm.rules:SUBSYSTEM!="block", GOTO="btrfs_end"
./main/usr/lib/udev/rules.d/64-btrfs-dm.rules:KERNEL!="dm-[0-9]*", GOTO="btrfs_end"
./main/usr/lib/udev/rules.d/64-btrfs-dm.rules:ACTION!="add|change", GOTO="btrfs_end"
./main/usr/lib/udev/rules.d/64-btrfs-dm.rules:ENV{ID_FS_TYPE}!="btrfs", GOTO="btrfs_end"
./main/usr/lib/udev/rules.d/64-btrfs-dm.rules:# Once the device mapper symlink is created, tell btrfs about it
./main/usr/lib/udev/rules.d/64-btrfs-dm.rules:ENV{DM_NAME}=="?*", RUN{builtin}+="btrfs ready /dev/mapper/$env{DM_NAME}"
./main/usr/lib/udev/rules.d/64-btrfs-dm.rules:LABEL="btrfs_end"
./main/usr/lib/udev/rules.d/50-udev-default.rules:KERNEL=="btrfs-control", GROUP="disk"
./main/usr/lib/modules/6.12.38+deb13-amd64/modules.softdep:softdep btrfs pre: blake2b-256
./main/usr/lib/modules/6.12.38+deb13-amd64/modules.softdep:softdep btrfs pre: sha256