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IFF a blind retry is all that is needed it >> should be done in the core functionality. I fear it's not that easy, >> though. So do I. :) > > +1 > > This migration retry weirdness is a GUP issue, it needs to be solved > in the mm not exposed to every pin_user_pages caller. > > If it turns out ZONE_MOVEABLE pages can't actually be reliably moved > then it is pretty broken.. > OK, I'll work on finding out what is temporarily elevating the refcount and preventing the migration. And see where that leads. thanks, -- John Hubbard NVIDIA