On Wed, Feb 12, 2020 at 12:03 PM Al Viro <viro@xxxxxxxxxxxxxxxxxx> wrote: > > What's to prevent racing with fs shutdown while you are doing the second part? I was thinking that only the proc_flush_task() code would do this. And that holds a ref to the vfsmount through upid->ns. So I wasn't suggesting doing this in general - just splitting up the implementation of d_invalidate() so that proc_flush_task_mnt() could delay the complex part to after having traversed the RCU-protected list. But hey - I missed this part of the problem originally, so maybe I'm just missing something else this time. Wouldn't be the first time. Linus