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Subject: Re: [PATCH 10/17] mm: rmap preparation for remap_anon_pages
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Andrea Arcangeli <aarcange@redhat.com>
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On Mon, Oct 6, 2014 at 12:41 PM, Andrea Arcangeli <aarcange@redhat.com> wrote:
>
> Of course if somebody has better ideas on how to resolve an anonymous
> userfault they're welcome.

So I'd *much* rather have a "write()" style interface (ie _copying_
bytes from user space into a newly allocated page that gets mapped)
than a "remap page" style interface

remapping anonymous pages involves page table games that really aren't
necessarily a good idea, and tlb invalidates for the old page etc.
Just don't do it.

           Linus