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Re: [Xen-devel] RFC: [0/2] Remove netloop by lazy copying in netback

To: Keir Fraser <keir@xxxxxxxxxxxxx>, Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>, Xen Development Mailing List <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] RFC: [0/2] Remove netloop by lazy copying in netback
From: Keir Fraser <keir@xxxxxxxxxxxxx>
Date: Tue, 20 Mar 2007 10:27:48 +0000
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On 20/3/07 10:22, "Keir Fraser" <keir@xxxxxxxxxxxxx> wrote:

> One other thought I had -- does the Linux network stack ever modify date
> residing outside the main skbuff data area (i.e., data in fragments)? If it
> ever does, wouldn't your delayed copy in netback potentially race such
> updates? If the Linux network stack guarantees never to do such a thing,
> that would be nice for us. :-)

Scrub that question: we already map the grants read-only, so the network
stack can't be trying to write to fragments.

 -- Keir

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