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 X-Spam-Level: X-Spam-Status: No, score=-15.4 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7BB11C432BE for ; Thu, 5 Aug 2021 02:36:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6088A60E78 for ; Thu, 5 Aug 2021 02:36:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234582AbhHECgW (ORCPT ); Wed, 4 Aug 2021 22:36:22 -0400 Received: from szxga01-in.huawei.com ([45.249.212.187]:7785 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229807AbhHECgV (ORCPT ); Wed, 4 Aug 2021 22:36:21 -0400 Received: from dggemv704-chm.china.huawei.com (unknown [172.30.72.56]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4GgCQl1QDgzYlGn; Thu, 5 Aug 2021 10:35:59 +0800 (CST) Received: from dggema769-chm.china.huawei.com (10.1.198.211) by dggemv704-chm.china.huawei.com (10.3.19.47) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256) id 15.1.2176.2; Thu, 5 Aug 2021 10:36:06 +0800 Received: from [10.174.179.215] (10.174.179.215) by dggema769-chm.china.huawei.com (10.1.198.211) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2; Thu, 5 Aug 2021 10:36:04 +0800 Subject: Re: [PATCH -next] RDMA/hns: Fix return in hns_roce_rereg_user_mr() To: Leon Romanovsky CC: , , , , , , References: <20210804125939.20516-1-yuehaibing@huawei.com> From: YueHaibing Message-ID: Date: Thu, 5 Aug 2021 10:36:03 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.5.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.179.215] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To dggema769-chm.china.huawei.com (10.1.198.211) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2021/8/4 21:53, Leon Romanovsky wrote: > On Wed, Aug 04, 2021 at 08:59:39PM +0800, YueHaibing wrote: >> If re-registering an MR in hns_roce_rereg_user_mr(), we should >> return NULL instead of pass 0 to ERR_PTR. >> >> Fixes: 4e9fc1dae2a9 ("RDMA/hns: Optimize the MR registration process") >> Signed-off-by: YueHaibing >> --- >> drivers/infiniband/hw/hns/hns_roce_mr.c | 4 +++- >> 1 file changed, 3 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/infiniband/hw/hns/hns_roce_mr.c b/drivers/infiniband/hw/hns/hns_roce_mr.c >> index 006c84bb3f9f..7089ac780291 100644 >> --- a/drivers/infiniband/hw/hns/hns_roce_mr.c >> +++ b/drivers/infiniband/hw/hns/hns_roce_mr.c >> @@ -352,7 +352,9 @@ struct ib_mr *hns_roce_rereg_user_mr(struct ib_mr *ibmr, int flags, u64 start, >> free_cmd_mbox: >> hns_roce_free_cmd_mailbox(hr_dev, mailbox); >> >> - return ERR_PTR(ret); >> + if (ret) >> + return ERR_PTR(ret); >> + return NULL; >> } > > I don't understand this function, it returns or ERR_PTR() or NULL, but > should return &mr->ibmr in success path. How does it work? Did you means hns_roce_reg_user_mr()? hns_roce_rereg_user_mr() returns ERR_PTR() on failure, and return NULL on success, In ib_uverbs_rereg_mr(), old mr will be used if rereg_user_mr() return NULL, see: 829 new_mr = ib_dev->ops.rereg_user_mr(mr, cmd.flags, cmd.start, cmd.length, 830 cmd.hca_va, cmd.access_flags, new_pd, 831 &attrs->driver_udata); 832 if (IS_ERR(new_mr)) { 833 ret = PTR_ERR(new_mr); 834 goto put_new_uobj; 835 } 836 if (new_mr) { ..... 860 mr = new_mr; 861 } else { 862 if (cmd.flags & IB_MR_REREG_PD) { 863 atomic_dec(&orig_pd->usecnt); 864 mr->pd = new_pd; 865 atomic_inc(&new_pd->usecnt); 866 } 867 if (cmd.flags & IB_MR_REREG_TRANS) 868 mr->iova = cmd.hca_va; 869 } > > Thanks > >> >> int hns_roce_dereg_mr(struct ib_mr *ibmr, struct ib_udata *udata) >> -- >> 2.17.1 >> > . >