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Date: Thu, 5 May 2016 16:39:24 +0200
From: Andrea Arcangeli <aarcange@redhat.com>
Subject: Re: [BUG] vfio device assignment regression with THP ref counting
 redesign
Message-ID: <20160505143924.GC28755@redhat.com>
References: <20160428232127.GL11700@redhat.com>
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 <20160429070611.GA4990@node.shutemov.name>
 <20160429163444.GM11700@redhat.com>
 <20160502104119.GA23305@node.shutemov.name>
 <20160502152307.GA12310@redhat.com>
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To: Alex Williamson <alex.williamson@redhat.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>, kirill.shutemov@linux.intel.com, linux-kernel@vger.kernel.org, "linux-mm@kvack.org" <linux-mm@kvack.org>

Hello Alex,

On Wed, May 04, 2016 at 07:19:27PM -0600, Alex Williamson wrote:
> On Mon, 2 May 2016 20:03:07 +0200
> Andrea Arcangeli <aarcange@redhat.com> wrote:
> 
> > On Mon, May 02, 2016 at 07:00:42PM +0300, Kirill A. Shutemov wrote:
> > > Agreed. I just didn't see the two-refcounts solution.  
> > 
> > If you didn't do it already or if you're busy with something else,
> > I can change the patch to the two refcount solution, which should
> > restore the old semantics without breaking rmap.
> 
> I didn't see any follow-up beyond this nor patches on lkml.  Do we have
> something we feel confident for posting to v4.6 with a stable backport
> to v4.5?  Thanks,

I'm currently testing this: