On Wed, Feb 12, 2020 at 12:03 PM Al Viro [off-list ref] 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