pivot_root()?
pivot_root()?
Posted Mar 14, 2026 13:54 UTC (Sat) by Nikratio (subscriber, #71966)In reply to: pivot_root()? by NYKevin
Parent article: Practical uses for a null filesystem
> My (possibly wrong) interpretation is that this is not a filesystem-level restriction, but a mounting restriction. In other words, the problem is not that there's some specific "rootfs" filesystem that is unable to be pivoted. Rather, the problem is that, post-boot, the mount system is unable to represent a state where nothing is mounted. Presumably, the pivot_root() syscall would need to transition through such a state, and working around this limitation is either impossible or not worth the complexity.
I think that interpretation boils down to "the pivot _root system call fundamentally does not work", since pivoting ing the root filesystem is the one and only thing this system call is supposed to do. I highly doubt this would have been added if it never works.