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Date: Sun, 9 May 2010 18:32:32 -0700 (PDT)
From: Linus Torvalds <torvalds@linux-foundation.org>
To: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
cc: Mel Gorman <mel@csn.ul.ie>, Andrew Morton <akpm@linux-foundation.org>,
       Linux-MM <linux-mm@kvack.org>, LKML <linux-kernel@vger.kernel.org>,
       Minchan Kim <minchan.kim@gmail.com>, Christoph Lameter <cl@linux.com>,
       Andrea Arcangeli <aarcange@redhat.com>, Rik van Riel <riel@redhat.com>,
       Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH 2/2] mm,migration: Fix race between shift_arg_pages and
 rmap_walk by guaranteeing rmap_walk finds PTEs created within the temporary
 stack
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On Sun, 9 May 2010, Linus Torvalds wrote:
> 
> So I never disliked that patch. I'm perfectly happy with a "don't migrate 
> these pages at all, because they are in a half-way state in the middle of 
> execve stack magic".

Btw, I also think that Mel's patch could be made a lot _less_ magic by 
just marking that initial stack vma with a VM_STACK_INCOMPLETE_SETUP bit, 
instead of doing that "maybe_stack" thing. We could easily make that 
initial vma setup very explicit indeed, and then just clear that bit when 
we've moved the stack to its final position.

		Linus