From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Monjalon <thomas.monjalon@6wind.com>
Subject: Re: [PATCH] doc: add known issue for virtio TSO with
	clones
Date: Thu, 09 Feb 2017 07:05:05 -0800 (PST)
Message-ID: <2800951.RjD6d24Weo@xps13>
References: <1486387013-1706-1-git-send-email-olivier.matz@6wind.com>
 <20170206151047.155aa0aa@xeon-e3>
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Cc: dev@dpdk.org, yuanhan.liu@linux.intel.com, john.mcnamara@intel.com
To: Stephen Hemminger <stephen@networkplumber.org>,
 Olivier Matz <olivier.matz@6wind.com>
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2017-02-06 15:10, Stephen Hemminger:
> On Mon,  6 Feb 2017 14:16:53 +0100
> Olivier Matz <olivier.matz@6wind.com> wrote:
> 
> > +**Implication**:
> > +   In this situation, the shared data will be modified by the driver,
> > +   potentially causing race conditions with the other users of the mbuf
> > +   data.
> 
> This is a driver bug! The driver must check for refcount and not modify
> mbuf's whose refcnt > 1. For those mbuf's it should copy the mbuf and modify
> the copy. 
> 
> It is not good to force buggy refcnt handling back onto the application.
> It is acceptable to document the performance impact.

Everybody agree it is a bug.
Unfortunately, nobody has time to work on it in this release.
So it is better than nothing to document the bug.

Applied, thanks