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Date: Tue, 27 May 2014 09:34:22 -0500 (CDT)
From: Christoph Lameter <cl@gentwo.org>
To: Peter Zijlstra <peterz@infradead.org>
cc: Konstantin Khlebnikov <koct9i@gmail.com>,
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        Hal Rosenstock <hal.rosenstock@gmail.com>,
        Mike Marciniszyn <infinipath@intel.com>
Subject: Re: [RFC][PATCH 0/5] VM_PINNED
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On Tue, 27 May 2014, Peter Zijlstra wrote:

> The things I care about for VM_PINNED are long term pins, like the IB
> stuff, which sets up its RDMA buffers at the start of a program and
> basically leaves them in place for the entire duration of said program.

Ok that also means the pages are not to be allocated from ZONE_MOVABLE?

I expected the use of a page flag. With a vma flag we may have a situation
that mapping a page into a vma changes it to pinned and terminating a
process may unpin a page. That means the zone that the page should be
allocated from changes.

Pinned pages in ZONE_MOVABLE are not a good idea. But since "kernelcore"
is rarely used maybe that is not an issue?