On Fri, Mar 2, 2018 at 10:59 PM, Eric W. Biederman <ebiederm@xxxxxxxxxxxx> wrote: > The code has been missing a way for a ->get_acl method to not cache > a return value without risking invalidating a cached value > that was set while get_acl() was returning. > > Add that support by implementing to_uncachable_acl, to_cachable_acl, > is_uncacheable_acl, and dealing with uncachable acls in get_acl(). I don't like the pointer magic here. Can't the uncachable bit just be added to struct posix_acl? AFAICS that can be done even without increasing the size of that struct (e.g. by unioning it with the rcu_head). Thanks, Miklos
