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Message-ID: <1343290299.26034.84.camel@twins>
Subject: Re: [RFC] page-table walkers vs memory order
From: Peter Zijlstra <peterz@infradead.org>
To: Hugh Dickins <hughd@google.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Rik van Riel <riel@redhat.com>,
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Date: Thu, 26 Jul 2012 10:11:39 +0200
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On Wed, 2012-07-25 at 15:09 -0700, Hugh Dickins wrote:
> We find out after it hits us, and someone studies the disassembly -
> if we're lucky enough to crash near the origin of the problem. 

This is a rather painful way.. see

  https://lkml.org/lkml/2009/1/5/555

we were lucky there in that the lack of ACCESS_ONCE() caused an infinite
loop so we knew exactly where we got stuck.