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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 96B71C3F2CE for ; Sun, 1 Mar 2020 02:58:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6CF1320828 for ; Sun, 1 Mar 2020 02:58:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727228AbgCAC6I (ORCPT ); Sat, 29 Feb 2020 21:58:08 -0500 Received: from mail-pj1-f67.google.com ([209.85.216.67]:35966 "EHLO mail-pj1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726786AbgCAC6I (ORCPT ); Sat, 29 Feb 2020 21:58:08 -0500 Received: by mail-pj1-f67.google.com with SMTP id gv17so2934503pjb.1; Sat, 29 Feb 2020 18:58:07 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:autocrypt :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=D4MlvJRj68LMrS7IDPbO+oW/bka+rXu9QTiGNQT3WrE=; b=sV60QJbWtxYwUzl63TEEb4By2OcP2dW2a/IVxVc+amCTa33B58bJiwDqXbAeLICbbw kkmecNSYnHe3XSdn/D194VUELomcs29Eowv8uk832EdSf2kxm4lFQ2BhPnR5GwGaPMjm DcYO9KTr1yxbQrDpFJ9M/YzdIAft7FxdTBMDgEuL2gRIpN75OqNrI96C2Bzb0ee2ICuw iI12sk5dFKFAzGkoDw4wynLrDoDmPcrcuRt7kV4RboERygPK9fQ8PA1CfNBIEnKUg1MN Jx9ua2um8BIOPRZwV3nLRc0fulZTW877JZBQPoMHDG/Nn5/Hycp2uIxHtgQtkeA0mo6u MUPA== X-Gm-Message-State: APjAAAW0P3ao+lrm4B5C7hpigIBkmBwlEjfqTB3MUFFevkifyiayIX6f 0B1da0F9t5tMkkHDrrcZB5Y= X-Google-Smtp-Source: APXvYqySEvSPq5aQq2NXAwwzRcJoEJSGapgOqKZjldd2M0y8kpJRHJHlx9C5wy6hqoFm0JSDu3dSMQ== X-Received: by 2002:a17:90a:9416:: with SMTP id r22mr13501977pjo.2.1583031487129; Sat, 29 Feb 2020 18:58:07 -0800 (PST) Received: from ?IPv6:2601:647:4000:d7:bd83:6f94:8c5:942d? ([2601:647:4000:d7:bd83:6f94:8c5:942d]) by smtp.gmail.com with ESMTPSA id r198sm17215775pfr.54.2020.02.29.18.58.05 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 29 Feb 2020 18:58:06 -0800 (PST) Subject: Re: [PATCH v9 20/25] block/rnbd: server: main functionality To: Jack Wang , linux-block@vger.kernel.org, linux-rdma@vger.kernel.org Cc: axboe@kernel.dk, hch@infradead.org, sagi@grimberg.me, leon@kernel.org, dledford@redhat.com, jgg@ziepe.ca, danil.kipnis@cloud.ionos.com, jinpu.wang@cloud.ionos.com, rpenyaev@suse.de, pankaj.gupta@cloud.ionos.com References: <20200221104721.350-1-jinpuwang@gmail.com> <20200221104721.350-21-jinpuwang@gmail.com> From: Bart Van Assche Autocrypt: addr=bvanassche@acm.org; prefer-encrypt=mutual; keydata= mQENBFSOu4oBCADcRWxVUvkkvRmmwTwIjIJvZOu6wNm+dz5AF4z0FHW2KNZL3oheO3P8UZWr LQOrCfRcK8e/sIs2Y2D3Lg/SL7qqbMehGEYcJptu6mKkywBfoYbtBkVoJ/jQsi2H0vBiiCOy fmxMHIPcYxaJdXxrOG2UO4B60Y/BzE6OrPDT44w4cZA9DH5xialliWU447Bts8TJNa3lZKS1 AvW1ZklbvJfAJJAwzDih35LxU2fcWbmhPa7EO2DCv/LM1B10GBB/oQB5kvlq4aA2PSIWkqz4 3SI5kCPSsygD6wKnbRsvNn2mIACva6VHdm62A7xel5dJRfpQjXj2snd1F/YNoNc66UUTABEB AAG0JEJhcnQgVmFuIEFzc2NoZSA8YnZhbmFzc2NoZUBhY20ub3JnPokBOQQTAQIAIwUCVI67 igIbAwcLCQgHAwIBBhUIAgkKCwQWAgMBAh4BAheAAAoJEHFcPTXFzhAJ8QkH/1AdXblKL65M Y1Zk1bYKnkAb4a98LxCPm/pJBilvci6boefwlBDZ2NZuuYWYgyrehMB5H+q+Kq4P0IBbTqTa jTPAANn62A6jwJ0FnCn6YaM9TZQjM1F7LoDX3v+oAkaoXuq0dQ4hnxQNu792bi6QyVdZUvKc macVFVgfK9n04mL7RzjO3f+X4midKt/s+G+IPr4DGlrq+WH27eDbpUR3aYRk8EgbgGKvQFdD CEBFJi+5ZKOArmJVBSk21RHDpqyz6Vit3rjep7c1SN8s7NhVi9cjkKmMDM7KYhXkWc10lKx2 RTkFI30rkDm4U+JpdAd2+tP3tjGf9AyGGinpzE2XY1K5AQ0EVI67igEIAKiSyd0nECrgz+H5 PcFDGYQpGDMTl8MOPCKw/F3diXPuj2eql4xSbAdbUCJzk2ETif5s3twT2ER8cUTEVOaCEUY3 eOiaFgQ+nGLx4BXqqGewikPJCe+UBjFnH1m2/IFn4T9jPZkV8xlkKmDUqMK5EV9n3eQLkn5g lco+FepTtmbkSCCjd91EfThVbNYpVQ5ZjdBCXN66CKyJDMJ85HVr5rmXG/nqriTh6cv1l1Js T7AFvvPjUPknS6d+BETMhTkbGzoyS+sywEsQAgA+BMCxBH4LvUmHYhpS+W6CiZ3ZMxjO8Hgc ++w1mLeRUvda3i4/U8wDT3SWuHcB3DWlcppECLkAEQEAAYkBHwQYAQIACQUCVI67igIbDAAK CRBxXD01xc4QCZ4dB/0QrnEasxjM0PGeXK5hcZMT9Eo998alUfn5XU0RQDYdwp6/kMEXMdmT oH0F0xB3SQ8WVSXA9rrc4EBvZruWQ+5/zjVrhhfUAx12CzL4oQ9Ro2k45daYaonKTANYG22y //x8dLe2Fv1By4SKGhmzwH87uXxbTJAUxiWIi1np0z3/RDnoVyfmfbbL1DY7zf2hYXLLzsJR mSsED/1nlJ9Oq5fALdNEPgDyPUerqHxcmIub+pF0AzJoYHK5punqpqfGmqPbjxrJLPJfHVKy goMj5DlBMoYqEgpbwdUYkH6QdizJJCur4icy8GUNbisFYABeoJ91pnD4IGei3MTdvINSZI5e Message-ID: <33864f54-62af-cb5f-45fa-55a283dcd434@acm.org> Date: Sat, 29 Feb 2020 18:58:04 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 MIME-Version: 1.0 In-Reply-To: <20200221104721.350-21-jinpuwang@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 2020-02-21 02:47, Jack Wang wrote: > +static int dev_search_path_set(const char *val, const struct kernel_param *kp) > +{ > + char *dup; > + > + if (strlen(val) >= sizeof(dev_search_path)) > + return -EINVAL; > + > + dup = kstrdup(val, GFP_KERNEL); > + > + if (dup[strlen(dup) - 1] == '\n') > + dup[strlen(dup) - 1] = '\0'; > + > + strlcpy(dev_search_path, dup, sizeof(dev_search_path)); > + > + kfree(dup); > + pr_info("dev_search_path changed to '%s'\n", dev_search_path); > + > + return 0; > +} It is not necessary in this function to do memory allocation. Something like the following (untested) code should be sufficient: const char *p = strrchr(val, '\n') ? : val + strlen(val); snprintf(dev_search_path, sizeof(dev_search_path), "%.*s", (int)(p - val), val); How are concurrent attempts to change dev_search_path serialized? Thanks, Bart.