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Date: Tue, 23 Aug 2016 11:06:55 +0200
From: Michal Hocko <mhocko@kernel.org>
Subject: Re: [PATCH 09/10] vhost, mm: make sure that oom_reaper doesn't reap
 memory read by vhost
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To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>, "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>, linux-mm@kvack.org, Andrew Morton <akpm@linux-foundation.org>, Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>, David Rientjes <rientjes@google.com>, Vladimir Davydov <vdavydov@parallels.com>

On Tue 23-08-16 09:55:55, Michal Hocko wrote:
> On Tue 23-08-16 00:01:23, Michael S. Tsirkin wrote:
> [...]
> > Actually, vhost net calls out to tun which does regular copy_from_iter.
> > Returning 0 there will cause corrupted packets in the network: not a
> > huge deal, but ugly.  And I don't think we want to annotate run and
> > macvtap as well.
> 
> Hmm, OK, I wasn't aware of that path and being consistent here matters.
> If the vhost driver can interact with other subsystems then there is
> really no other option than hooking into the page fault path. Ohh well.

Here is a completely untested patch just for sanity check.
---