From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH net 1/1] net/af_iucv: don't use paged skbs for TX on HiperSockets Date: Tue, 10 Jan 2017 21:07:11 -0500 (EST) Message-ID: <20170110.210711.1780886001866499809.davem@davemloft.net> References: <20170110161034.82445-1-ubraun@linux.vnet.ibm.com> <20170110161034.82445-2-ubraun@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, linux-s390@vger.kernel.org, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, stable@vger.kernel.org To: ubraun@linux.vnet.ibm.com Return-path: Received: from shards.monkeyblade.net ([184.105.139.130]:34578 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935739AbdAKCHN (ORCPT ); Tue, 10 Jan 2017 21:07:13 -0500 In-Reply-To: <20170110161034.82445-2-ubraun@linux.vnet.ibm.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Ursula Braun Date: Tue, 10 Jan 2017 17:10:34 +0100 > From: Julian Wiedmann > > With commit e53743994e21 > ("af_iucv: use paged SKBs for big outbound messages"), > we transmit paged skbs for both of AF_IUCV's transport modes > (IUCV or HiperSockets). > The qeth driver for Layer 3 HiperSockets currently doesn't > support NETIF_F_SG, so these skbs would just be linearized again > by the stack. > Avoid that overhead by using paged skbs only for IUCV transport. > > cc stable, since this also circumvents a significant skb leak when > sending large messages (where the skb then needs to be linearized). > > Signed-off-by: Julian Wiedmann > Signed-off-by: Ursula Braun > Cc: # v4.8+ > Fixes: e53743994e21 ("af_iucv: use paged SKBs for big outbound messages") Applied.