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Date: Mon, 14 Dec 2015 21:09:31 +0800
From: Yuanhan Liu <yuanhan.liu@linux.intel.com>
To: Thomas Monjalon <thomas.monjalon@6wind.com>
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Cc: dev@dpdk.org
Subject: Re: [dpdk-dev] [PATCH] virtio: fix virtio_net_hdr desc pointing to
 the same buffer
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On Mon, Dec 14, 2015 at 01:44:54PM +0100, Thomas Monjalon wrote:
> 2015-12-14 19:47, Yuanhan Liu:
> > On Mon, Dec 14, 2015 at 10:32:24AM +0100, Thomas Monjalon wrote:
> > > 2015-12-14 11:01, Yuanhan Liu:
> > > > On Fri, Dec 11, 2015 at 12:07:32AM +0800, Huawei@dpdk.org wrote:
> > > > > The virtio_net_hdr desc all pointed to the same buffer. It doesn't cause
> > > > > issue because in the simple TX mode we don't use the header. This patch
> > > > > makes the header desc point to different buffer.
> > > > > 
> > > > > Signed-off-by: Huawei Xie <huawei.xie@intel.com>
> > > > 
> > > > Acked-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
> > > 
> > > Does it fix something in the current behaviour?
> > 
> > It's more like a logic fixing to me.
> > 
> > > I have the feeling it may wait for 2.3.
> > 
> > It's been introduced in v2.2, with Huawei's simple tx patchset.
> > Therefore, I guess 2.2 is good to go?
> 
> The vhost driver has been validated without with patch.

Huawei stated in the commit log that "It doesn't cause issue because in
the simple TX mode we don't use the header".

> Merging it would be taking the risk of breaking something
> (or just reduce performance) for no clear benefit.
> Am I missing something?

I know your concerns: we really should be cagy about making any changes
when a release is close, especially when all stuff are validated. From
this point of view, I agree with you we could delay it to v2.3.

Maybe huawei have more inputs here?

	--yliu