From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: RE: [PATCH] net/hyperv: fix erroneous NETDEV_TX_BUSY use
Date: Wed, 14 Mar 2012 13:14:32 -0700
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Cc: Ben Greear <greearb@candelatech.com>,
	David Miller <davem@davemloft.net>,
	netdev <netdev@vger.kernel.org>,
	KY Srinivasan <kys@microsoft.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Haiyang Zhang <haiyangz@microsoft.com>
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On Wed, 2012-03-14 at 20:00 +0000, Haiyang Zhang wrote:

> Actually, I'm working on this bug, and have a patch under our internal 
> review now. My fix is actually not freeing the SKB, and return NETDEV_TX_BUSY.
> 
> Even if the vmbus ring buffer is busy currently, it can be available during
> the next re-try, because the host is taking away data from ring buffer. The 
> stop/wake queue mechanism is in the netvsc.c file.
> 
> In the out-of-memory case, dropping packet and return NETDEV_TX_OK seems fine.

That will be fine for net-next.

I sent a patch for current kernels, where obvious and minimal fixes
apply.