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Date: Fri, 1 Aug 2014 02:10:37 -0700 (PDT)
From: David Rientjes <rientjes@google.com>
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To: Johannes Weiner <hannes@cmpxchg.org>
cc: Andrew Morton <akpm@linux-foundation.org>,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Rik van Riel <riel@redhat.com>, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org
Subject: Re: [patch 2/3] mm, oom: remove unnecessary check for NULL
 zonelist
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On Thu, 31 Jul 2014, Johannes Weiner wrote:

> out_of_memory() wants the zonelist that was used during allocation,
> not just the random first node's zonelist that's simply picked to
> serialize page fault OOM kills system-wide.
> 
> This would even change how panic_on_oom behaves for page fault OOMs
> (in a completely unpredictable way) if we get CONSTRAINED_CPUSET.
> 
> This change makes no sense to me.
> 

Allocations during fault will be constrained by the cpuset's mems, if we 
are oom then why would we panic when panic_on_oom == 1?