Title: LVM2 default USE flag change
Author: David Seifert <firstname.lastname@example.org>
The Gentoo Base System team has recently switched from the disabling
"device-mapper-only" flag to the enabling "lvm" (bug #718910).
After considering most reverse dependencies of sys-fs/lvm2, the Base System Team
has decided that the majority of Gentoo users are unlikely to use the LVM2
components of sys-fs/lvm2, instead relying solely on it providing device-mapper
To this end, we will disable the default enabled flag "+lvm" on sys-fs/lvm2
on 2023-01-01. If you do not have USE=lvm somehow globally enabled, this means
you will lose LVM2 (but not device-mapper!) functionality, so enable it in your
config if your boot configuration depends on it or if you depend on any of the
If you use LVM2 for any partitions, or if you use tools like 'lvchange', you
should enable USE=lvm.
Furthermore, we have considered other default enabled USE flags too, and have
come to the conclusion that USE=+thin makes even less sense than USE=+lvm.
Thin-provisioned LVM volumes are an important use case in certain VM hosting
scenarios, but unlikely to be relevant for the large majority of Gentoo users.
- Enable USE="lvm" if you use lvm2 (but not needed for device-mapper) as described above.
This includes using LVM for any partitions.
- Enable USE="lvm thin" if you use thin as described above.
- If you don't know what LVM2 is, you don't need to take any action.