From: Vitaly Kuznetsov <vkuznets@redhat.com>
To: David Miller <davem@davemloft.net>
Cc: David.Laight@ACULAB.COM, haiyangz@microsoft.com,
netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
kys@microsoft.com, jasowang@redhat.com
Subject: Re: [PATCH net-next RFC] net: increase LL_MAX_HEADER for Hyper-V
Date: Thu, 17 Sep 2015 11:03:25 +0200 [thread overview]
Message-ID: <87k2rpwh7m.fsf@vitty.brq.redhat.com> (raw)
In-Reply-To: <20150916.105936.2275139635170756984.davem@davemloft.net> (David Miller's message of "Wed, 16 Sep 2015 10:59:36 -0700 (PDT)")
David Miller <davem@davemloft.net> writes:
> From: David Laight <David.Laight@ACULAB.COM>
> Date: Wed, 16 Sep 2015 16:25:03 +0000
>
>> Am I right in thinking this is adding an extra 96 unused bytes to the front
>> of almost all skb just so that hyper-v can make its link level header
>> contiguous with whatever follows (IP header ?).
>>
>> Doesn't sound ideal.
>
> Agreed, this is rediculous, and the entire stack will incur this cost
> just because hyperv is enabled in the kernel config.
That's what 'RFC' in the subject was about :-)
We already have a precedent of increasing LL_MAX_HEADER globaly because
of a config option (CONFIG_MAC80211_MESH) but Hyper-V needs more.
--
Vitaly
prev parent reply other threads:[~2015-09-17 9:03 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-09-16 15:50 Vitaly Kuznetsov
2015-09-16 16:08 ` Haiyang Zhang
2015-09-16 16:25 ` David Laight
2015-09-16 17:26 ` Alexander Duyck
2015-09-16 17:55 ` KY Srinivasan
2015-09-16 21:38 ` Alexander Duyck
2015-09-16 22:57 ` KY Srinivasan
2015-09-16 23:48 ` Alexander Duyck
2015-09-16 23:58 ` KY Srinivasan
2015-09-17 8:38 ` David Laight
2015-09-17 15:14 ` KY Srinivasan
2015-09-17 18:52 ` David Miller
2015-09-17 19:52 ` KY Srinivasan
2015-09-17 20:10 ` David Miller
2015-09-17 21:16 ` KY Srinivasan
2015-09-16 17:59 ` David Miller
2015-09-17 9:03 ` Vitaly Kuznetsov [this message]
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