Re: [PATCH] in-core AFS multiplexor and PAG support

[Trond Myklebust <trond.myklebust@fys.uio.no>]

>>>>> " " == Linus Torvalds <torvalds@transmeta.com> writes:

     > Put another way: you'd usually add the PAG's at filesystem
     > _mount_ time, no? And at that point you'd usually want to add
     > it "retroactively" to the session processes that caused the
     > mount to happen, no? Not just to the children of the mount.

Think of PAGs as "session"-style management of credentials. If you
want to add/remove a credential without sharing that operation with
all the other processes that are currently in the same session/PAG
then you change PAGs.
Otherwise, the credential operation affects all processes in the same
PAG.

Under normal circumstances, changing real uid/gid should involve
changing your PAG, but it doesn't necessarily have to do so.

Cheers,
  Trond