From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754059AbeD3BeY (ORCPT ); Sun, 29 Apr 2018 21:34:24 -0400 Received: from shards.monkeyblade.net ([184.105.139.130]:54024 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753839AbeD3BeT (ORCPT ); Sun, 29 Apr 2018 21:34:19 -0400 Date: Sun, 29 Apr 2018 21:34:17 -0400 (EDT) Message-Id: <20180429.213417.1622456092178936722.davem@davemloft.net> To: edumazet@google.com Cc: netdev@vger.kernel.org, luto@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, ka-cheong.poon@oracle.com, eric.dumazet@gmail.com Subject: Re: [PATCH v4 net-next 0/2] tcp: mmap: rework zerocopy receive From: David Miller In-Reply-To: <20180427155809.79094-1-edumazet@google.com> References: <20180427155809.79094-1-edumazet@google.com> X-Mailer: Mew version 6.7 on Emacs 25.3 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eric Dumazet Date: Fri, 27 Apr 2018 08:58:07 -0700 > syzbot reported a lockdep issue caused by tcp mmap() support. > > I implemented Andy Lutomirski nice suggestions to resolve the > issue and increase scalability as well. > > First patch is adding a new getsockopt() operation and changes mmap() > behavior. > > Second patch changes tcp_mmap reference program. > > v4: tcp mmap() support depends on CONFIG_MMU, as kbuild bot told us. > > v3: change TCP_ZEROCOPY_RECEIVE to be a getsockopt() option > instead of setsockopt(), feedback from Ka-Cheon Poon > > v2: Added a missing page align of zc->length in tcp_zerocopy_receive() > Properly clear zc->recv_skip_hint in case user request was completed. Looks great, series applied, thanks Eric.