Daniel Xu writes:
User extended attributes are useful as metadata storage for kernfs consumers like cgroups. Especially in the case of cgroups, it is useful to have a central metadata store that multiple processes/services can use to coordinate actions. A concrete example is for userspace out of memory killers. We want to let delegated cgroup subtree owners (running as non-root) to be able to say "please avoid killing this cgroup". This is especially important for desktop linux as delegated subtrees owners are less likely to run as root. The first two commits set up some stuff for the third commit which intro introduce a new flag, KERNFS_ROOT_SUPPORT_USER_XATTR, that lets kernfs consumers enable user xattr support. The final commit turns on user xattr support for cgroupfs.
The whole series looks good to me, thanks. For the whole series: Acked-by: Chris Down <chris@xxxxxxxxxxxxxx>
