From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH] batman-adv: Revert "use core MTU range checking in misc drivers" Date: Wed, 26 Oct 2016 17:20:14 -0400 (EDT) Message-ID: <20161026.172014.1445485460255687424.davem@davemloft.net> References: <20161022074624.30033-1-sven@narfation.org> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, b.a.t.m.a.n@lists.open-mesh.org, linux-kernel@vger.kernel.org, jarod@redhat.com To: sven@narfation.org Return-path: In-Reply-To: <20161022074624.30033-1-sven@narfation.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: Sven Eckelmann Date: Sat, 22 Oct 2016 09:46:24 +0200 > The maximum MTU is defined via the slave devices of an batman-adv > interface. Thus it is not possible to calculate the max_mtu during the > creation of the batman-adv device when no slave devices are attached. Doing > so would for example break non-fragmentation setups which then > (incorrectly) allow an MTU of 1500 even when underlying device cannot > transport 1500 bytes + batman-adv headers. > > Checking the dynamically calculated max_mtu via the minimum of the slave > devices MTU during .ndo_change_mtu is also used by the bridge interface. > > Cc: Jarod Wilson > Fixes: b3e3893e1253 ("net: use core MTU range checking in misc drivers") > Signed-off-by: Sven Eckelmann Applied, thanks.