Date: Wed, 7 Aug 2013 13:58:04 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Ed Cashin <ecashin@coraid.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] aoe: adjust ref of head for compound page tails
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On Thu, 1 Aug 2013 21:29:59 -0400 Ed Cashin <ecashin@coraid.com> wrote:

> As discussed previously,

I think I missed that.

> the fact that some users of the block
> layer provide bios that point to pages with a zero _count means
> that it is not OK for the network layer to do a put_page on the
> skb frags during an skb_linearize, so the aoe driver gets a
> reference to pages in bios and puts the reference before ending
> the bio.  And because it cannot use get_page on a page with a
> zero _count, it manipulates the value directly.

Eh?  What code is putting count==0 pages into bios?  That sounds very
weird and broken.


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