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 E5679C433EF for ; Wed, 2 Mar 2022 07:28:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239882AbiCBH3j (ORCPT ); Wed, 2 Mar 2022 02:29:39 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57922 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236844AbiCBH3U (ORCPT ); Wed, 2 Mar 2022 02:29:20 -0500 Received: from out30-57.freemail.mail.aliyun.com (out30-57.freemail.mail.aliyun.com [115.124.30.57]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 70CF651E51; Tue, 1 Mar 2022 23:28:36 -0800 (PST) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R621e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e01424;MF=guwen@linux.alibaba.com;NM=1;PH=DS;RN=7;SR=0;TI=SMTPD_---0V61g7Jq_1646206113; Received: from 30.225.24.118(mailfrom:guwen@linux.alibaba.com fp:SMTPD_---0V61g7Jq_1646206113) by smtp.aliyun-inc.com(127.0.0.1); Wed, 02 Mar 2022 15:28:34 +0800 Message-ID: <82bd43af-1d90-4395-b868-4a045bf4a47b@linux.alibaba.com> Date: Wed, 2 Mar 2022 15:28:32 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:91.0) Gecko/20100101 Thunderbird/91.4.0 Subject: Re: [PATCH net] net/smc: fix unexpected SMC_CLC_DECL_ERR_REGRMB error To: "D. Wythe" , kgraul@linux.ibm.com Cc: kuba@kernel.org, davem@davemloft.net, netdev@vger.kernel.org, linux-s390@vger.kernel.org, linux-rdma@vger.kernel.org References: <1646140644-121649-1-git-send-email-alibuda@linux.alibaba.com> From: Wen Gu In-Reply-To: <1646140644-121649-1-git-send-email-alibuda@linux.alibaba.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-s390@vger.kernel.org 在 2022/3/1 下午9:17, D. Wythe 写道: > From: "D. Wythe" > > Remove connections from link group is not synchronous with handling > SMC_LLC_DELETE_RKEY, which means that even the number of connections is > less that SMC_RMBS_PER_LGR_MAX, it does not mean that the connection can > register rtoken successfully later, in other words, the rtoken entry may > have not been released. This will cause an unexpected > SMC_CLC_DECL_ERR_REGRMB to be reported, and then ths smc connection have > to fallback to TCP. > IMHO, if there are SMC_RMBS_PER_LGR_MAX connections in the link group now, one of them is being removed and here comes a new connection at this moment, then: (1) without this patch, the new connection will be added into the old link group but fallback if the removing connection has not finished unregistering its rmb. (2) with this patch, a new link group will be created and the new connection will be added into the new link group. I am wondering if (1) should be considered as a issue, or just a bydesign? If it is a issue, I think this patch works, Thanks! Reviewed-by: Wen Gu Best Regards, Wen Gu