From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: [PATCH] net: Add default_advmss() methods to blackhole dst_ops Date: Fri, 18 Feb 2011 14:33:25 +0100 Message-ID: <1298036005.6201.58.camel@edumazet-laptop> References: <20110218050321.10415.qmail@science.horizon.com> <1298010735.2642.9.camel@edumazet-laptop> <1298023023.2595.170.camel@edumazet-laptop> <1298035443.6201.51.camel@edumazet-laptop> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: George Spelvin , David Miller , linux-kernel@vger.kernel.org, netdev , Roland Dreier To: Changli Gao Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Le vendredi 18 f=C3=A9vrier 2011 =C3=A0 21:29 +0800, Changli Gao a =C3=A9= crit : > On Fri, Feb 18, 2011 at 9:24 PM, Eric Dumazet wrote: > > Le vendredi 18 f=C3=A9vrier 2011 =C3=A0 21:16 +0800, Changli Gao a = =C3=A9crit : > > > >> I am wondering why magic number 256 is used here. Is there a speci= al > >> reason? Thanks. > >> > > > > It really doesnt matter. SYN message will be dropped anyway. > > > > 256 happens to be the default value > > of /proc/sys/net/ipv4/route/min_adv_mss > > >=20 > Thanks for your explaining. IMHO, ip_rt_min_advmss is better than a > magic number, here. >=20 I had this exact idea but found we need struct net pointer to get this value, not provided in parameters, so I falled back to the 256 value.