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Date: Thu, 10 Sep 2020 14:19:56 -0300
From: Jason Gunthorpe <jgg@ziepe.ca>
To: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Subject: Re: [RFC PATCH v2 1/3] mm/gup: fix gup_fast with dynamic page table
 folding
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On Thu, Sep 10, 2020 at 07:07:57PM +0200, Gerald Schaefer wrote:

> I might have lost track a bit. Are we still talking about possible
> functional impacts of either our current pagetable walking with s390
> (apart from gup_fast), or the proposed generic change (for s390, or
> others?)?

I'm looking for an more understandable explanation what is wrong with
the S390 implementation.

If the page operations require the invariant I described then it is
quite easy to explain the problem and understand the solution.

Jason