From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: RE: [PATCH 1/1] net/hyperv: Fix the code handling tx busy
Date: Mon, 19 Mar 2012 11:30:58 -0700
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Cc: Stephen Hemminger <shemminger@vyatta.com>,
	KY Srinivasan <kys@microsoft.com>,
	"davem@davemloft.net" <davem@davemloft.net>,
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To: Haiyang Zhang <haiyangz@microsoft.com>
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On Mon, 2012-03-19 at 17:50 +0000, Haiyang Zhang wrote:

> As in my previous reply to Eric --
> We actually stop queue when the ring buffer is busy, see the code in netvsc.c
> 
> I have tested with one CPU. After NETDEV_TX_BUSY is returned, the Linux guest OS
> continues to respond without any problem.

Then something is wrong somewhere.

Dont hide a bug adding a trick.

If you ever return NETDEV_TX_BUSY from start_xmit(), then you MUST call
netif_tx_stop_queue() as well right before.

I believe I already told this before...