From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D6647C433F5 for ; Tue, 8 Mar 2022 07:58:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344714AbiCHH66 (ORCPT ); Tue, 8 Mar 2022 02:58:58 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44262 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237428AbiCHH64 (ORCPT ); Tue, 8 Mar 2022 02:58:56 -0500 Received: from smtp.tom.com (smtprz15.163.net [106.3.154.248]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F24EF1E3C2 for ; Mon, 7 Mar 2022 23:57:59 -0800 (PST) Received: from my-app01.tom.com (my-app01.tom.com [127.0.0.1]) by freemail01.tom.com (Postfix) with ESMTP id 772E31E8C276 for ; Tue, 8 Mar 2022 15:57:57 +0800 (CST) Received: from my-app01.tom.com (HELO smtp.tom.com) ([127.0.0.1]) by my-app01 (TOM SMTP Server) with SMTP ID -382177656 for ; Tue, 08 Mar 2022 15:57:57 +0800 (CST) Received: from antispam3.tom.com (unknown [172.25.16.54]) by freemail01.tom.com (Postfix) with ESMTP id 622C81E8C1EC for ; Tue, 8 Mar 2022 15:57:57 +0800 (CST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=tom.com; s=201807; t=1646726277; bh=VE2APZ2EUOPto3xCBpDlYUdKULx5+IcuTAJTyrhmCSY=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=TNT6WwpA6WPDWkpnUpBeyhZ3XaXoCUbuYbSiYJQMfBC4HMHd1xTBLGZ6JMbizzmCX dqxSgolOwBa0WAn5mM2dMrLv53vMSIpVc1JQZeCGl4qCfjHolHXGZI34gQMLFb90+D rfv36HFA6yHB/TqABxeBkaso7WNc3Cig1h8TIDPg= Received: from antispam3.tom.com (antispam3.tom.com [127.0.0.1]) by antispam3.tom.com (Postfix) with ESMTP id 3C6949C1C1F for ; Tue, 8 Mar 2022 15:57:57 +0800 (CST) X-Virus-Scanned: Debian amavisd-new at antispam3.tom.com Received: from antispam3.tom.com ([127.0.0.1]) by antispam3.tom.com (antispam3.tom.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 97zfaMQx5y_b for ; Tue, 8 Mar 2022 15:57:56 +0800 (CST) Received: from localhost (unknown [223.104.210.22]) by antispam3.tom.com (Postfix) with ESMTPA id 4B4899C0839; Tue, 8 Mar 2022 15:57:55 +0800 (CST) Date: Tue, 8 Mar 2022 15:57:54 +0800 From: Mingbao Sun To: Christoph Hellwig Cc: Keith Busch , Jens Axboe , Sagi Grimberg , Chaitanya Kulkarni , linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, tyler.sun@dell.com, ping.gan@dell.com, yanxiu.cai@dell.com, libin.zhang@dell.com, ao.sun@dell.com Subject: Re: [PATCH 2/2] nvme-tcp: support specifying the congestion-control Message-ID: <20220308155754.000029bb@tom.com> In-Reply-To: <20220308071227.GB24575@lst.de> References: <20220304092754.2721-1-sunmingbao@tom.com> <20220304092754.2721-3-sunmingbao@tom.com> <20220304162032.GA12250@lst.de> <20220305150915.00006b44@tom.com> <20220308071227.GB24575@lst.de> X-Mailer: Claws Mail 3.18.0 (GTK+ 2.24.33; x86_64-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 8 Mar 2022 08:12:27 +0100 Christoph Hellwig wrote: > On Sat, Mar 05, 2022 at 03:09:15PM +0800, Mingbao Sun wrote: > > Well, actually I did have thought whether the calling of network API > > here is proper. Since I did find that there is no call to APIs of > > PCI/RDMA/TCP in fabrics.c. > > Yes - for a good reason. Without networking support your patch won't > even compile (both the host and target side). accept. Will remove the calls to networking APIs in the next version. With investigation, I found the tcp_congestion could also get checked later within sock_common_setsockopt in nvme_tcp_alloc_queue. And this brings no difference to the command 'nvme connect'. > > > But I hope the following could make a defense for it: > > > > Anyway, we need to validate the tcp_congestion passed in from > > user-space, right? > > Do we? It seems like no one else really calls this routine to verify > things. In fact it has no modular users at all in the current tree. OK. Got it. > > > The role of nvmf_parse_options is similar to that of > > drivers/nvme/target/configfs.c from the target side. > > And both of them can not avoid handling specific options of the > > sub-classes (e.g., NVMF_OPT_HDR_DIGEST, NVMF_OPT_TOS, NVMF_OPT_KATO). > > NVMF_OPT_KATO is completely generic, but yes, there other two are > transport specific. None of them calls out into other modules > that would need dependecies, though. Yeah, NVMF_OPT_KATO is generic. Sorry for the mistake. > > I'm also a little concerned that no other in kernel user like iSCSI, > NBD or NFS has any code like this. Well, at least I could first remove the calls to networking APIs on the host side. And it brings no downside.