Received: by 10.192.165.148 with SMTP id m20csp3261794imm; Sun, 29 Apr 2018 18:34:59 -0700 (PDT) X-Google-Smtp-Source: AB8JxZoAMYuohM8w/YVVxzTOqQD3NeXSdBrmh+wsS9lVV2H7u3UWUFq8U3P5tlkJ+KCGQL5bHkcN X-Received: by 2002:a63:a54f:: with SMTP id r15-v6mr9007122pgu.236.1525052099565; Sun, 29 Apr 2018 18:34:59 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1525052099; cv=none; d=google.com; s=arc-20160816; b=bNDLSj+RE1Tp1eDQDy6SJvIIGB9TJ+fDrp6UxA7rMNVgIAMLI/nJ5LzGuOEhJ6lmFS L2ba9PR2zMhXu3mRW928Q0Fy3uCmGJy2DkylSCtFgqJOx+7wswZnE2f4LLOC+AgZXw5o Ihmn54ciJETL7Dpvmwnoph9crQd3brzch1QrsS2LCF87gPAOnFUqs3jho9CKgnYIOTby nQr2uXQchEaRWkIwSvgjAu5lYdZa7yX8Pw/4FVsk80MICen1u3d6HnD92N5c6jt7ZENO TqWCS/LLw80HL/Zi8rZATvKRyV2sAg6qVGRrQ6E6eIWw/rk7UXvTi3lfSgm29X09bzsi Q9jg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding:mime-version :references:in-reply-to:from:subject:cc:to:message-id:date :arc-authentication-results; bh=I7pJk2k8DDod+JAJgXoNmFp26JcvhaXS3q7VBrujzZA=; b=gxH5WhOImygFNjNdON8pEA2n8Jjx6k+E6CMl7t/7DEGH9wtvtUz49FFimocUsbMO5r rKWsUY+Q57GEtlHJD4C/5mQss8Sa/exjXCI1L+w/F07LdMRoikCoW6b+sefq3udLzhj5 4y76OcevqO74RvjSisbMc2jiCNHFuOoNS+a1mcoc9jZpx+E3kzPGNKBsHossDF6SkwH+ cA7iAcVcDBZVrwFk1EWIo7Aqed2VwPfOxg0r8hIrvzby/acxAdz92nt5kVQdY5T4COWA x2LDj95Rluzvf5sj7EnNTzAz8ADn3irZpjL4DLvVYaFbvYLh0WNSvQCD6TeiFxVo/ZMr bCLg== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id h4-v6si6388107pls.490.2018.04.29.18.34.45; Sun, 29 Apr 2018 18:34:59 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754045AbeD3BeX (ORCPT + 99 others); Sun, 29 Apr 2018 21:34:23 -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 Received: from localhost (pool-173-77-163-54.nycmny.fios.verizon.net [173.77.163.54]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 1E70210938E79; Sun, 29 Apr 2018 18:34:18 -0700 (PDT) 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 X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Sun, 29 Apr 2018 18:34:18 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk 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.