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From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH v8 3/3] net: hisilicon: new hip04 ethernet driver
Date: Wed, 10 Dec 2014 11:07:32 -0500 (EST)
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From: Arnd Bergmann <arnd@arndb.de>
Date: Wed, 10 Dec 2014 10:35:20 +0100

> On Wednesday 10 December 2014 14:45:29 Ding Tianhong wrote:
>> 
>> Miss this code, I think the best way is skb_orphan(skb), just like the cxgb3 drivers, some hardware
>> didn't use the tx inq to free dmad Tx packages.
> 
> The problem with skb_orphan is that you are telling the network stack that
> the packet is now out of its reach and it will no longer be able to take
> queued packets into account.

skb_orphan() also does not release netfilter resources attached to the
packet.

Really, all drivers must free TX SKBs in a small, finite, amount of
time after submission.

There is no way around this.