[PATCH v3 hmm 08/12] mm/hmm: Remove racy protection against double-unregistration

[Christoph Hellwig]

On Tue, Jun 18, 2019 at 03:57:57PM -0300, Jason Gunthorpe wrote:
> With the previous loose coupling of the mirror and the range some code
> might rance to try to create a range without a mirror, which will now
> reliably crash with the poison.
> 
> It isn't so much the double unregister that worries me, but racing
> unregister with range functions.

Oh well.  It was just a nitpick for the highly unusual code patterns
in the two unregister routines, probably not worth fighting over even
if I still don't see the point.