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Subject: Re: [RFC][PATCH 00/26] sched/numa
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Avi Kivity <avi@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
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Date: Tue, 20 Mar 2012 12:07:13 +0100
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On Tue, 2012-03-20 at 12:52 +0200, Avi Kivity wrote:

> You use the dma engine for eager copying, not on demand.

Sure, but during that time no access to that entire vma is allowed, so
you have to unmap it, and any fault in there will have to wait for the
entire copy to complete.

Or am I misunderstanding how things would work?