On Tue, Aug 11, 2020 at 09:09:36AM -0700, Linus Torvalds wrote: > On Tue, Aug 11, 2020 at 9:05 AM Al Viro <viro@xxxxxxxxxxxxxxxxxx> wrote: > > > > Except that you suddenly see non-directory dentries get children. > > And a lot of dcache-related logics needs to be changed if that > > becomes possible. > > Yeah, I think you'd basically need to associate a (dynamic) > mount-point to that path when you start doing O_ALT. Or something. Whee... That's going to be non-workable for xattrs - fgetxattr() needs to work after unlink(). And you'd obviously need to prevent crossing into that sucker on normal lookups, which would add quite a few interesting twists around the automount points. I'm not saying it's not doable, but it won't be anywhere near straightforward. And API semantics questions are still there...