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=-6.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,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 94E47C433DF for ; Fri, 31 Jul 2020 04:06:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7A1B12070B for ; Fri, 31 Jul 2020 04:06:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726305AbgGaEGq (ORCPT ); Fri, 31 Jul 2020 00:06:46 -0400 Received: from mail-pj1-f68.google.com ([209.85.216.68]:40725 "EHLO mail-pj1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725800AbgGaEGp (ORCPT ); Fri, 31 Jul 2020 00:06:45 -0400 Received: by mail-pj1-f68.google.com with SMTP id t15so6556585pjq.5; Thu, 30 Jul 2020 21:06:45 -0700 (PDT) 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=QQ35CE9yJFKcx/uvB2EsoL6aQNmrJJ39h4x1UksSOeI=; b=oCx+OmtDmgcsKf4YV1IAtnHqhz2Y2qhro0Yby9520SONIWBEE4vGbr/7AEmTzsHiaC ENPpUWZbkekLE0dIoQ2AMdn4UfxLEDJujY7rHCZGZiPXokRNbo7z2o98NSAidR2AmgQ7 Ev0s4tZJe85EkW5GeA5nZ2vvC8qa7Ik1jx26X6pNvlgDHab5ALPNAKkj+WxA6PfBMDy+ 4pUAl3GnLEmAq92Jl+ERBx7zpGTO/s2hu/LKEsnpCf2hXEHhkyzaKYsqy9F0FJkmscj9 +o4ShmPav8WOVhuLbG8RiLpE+uwVVvF25ry4cyuhP0lmp7xwHEGtdyoTSYdZWHwMrfuK 8UAw== X-Gm-Message-State: AOAM530q1ohsa0E8RzsK4H2iDp3RM6SIZBb12aBcnuwXbxsTwXq4nCeS 7DMnmlmfnuvDlHvwaL0aCro= X-Google-Smtp-Source: ABdhPJzXnGsmXXgO8qRrgHFnZCn5E/++s0JbD0mUM5v850qtfGXGD2zI4A5vvBBtJhqa9flYfth/vQ== X-Received: by 2002:a17:902:ff13:: with SMTP id f19mr2147996plj.326.1596168404804; Thu, 30 Jul 2020 21:06:44 -0700 (PDT) Received: from [192.168.50.147] (c-73-241-217-19.hsd1.ca.comcast.net. [73.241.217.19]) by smtp.gmail.com with ESMTPSA id r8sm8054046pfg.147.2020.07.30.21.06.41 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 30 Jul 2020 21:06:43 -0700 (PDT) Subject: Re: [PATCH v4] scsi: ufs: Cleanup completed request without interrupt notification To: Stanley Chu , Avri Altman Cc: "linux-scsi@vger.kernel.org" , "martin.petersen@oracle.com" , "alim.akhtar@samsung.com" , "jejb@linux.ibm.com" , "beanhuo@micron.com" , "asutoshd@codeaurora.org" , "cang@codeaurora.org" , "matthias.bgg@gmail.com" , "linux-mediatek@lists.infradead.org" , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "kuohong.wang@mediatek.com" , "peter.wang@mediatek.com" , "chun-hung.wu@mediatek.com" , "andy.teng@mediatek.com" , "chaotian.jing@mediatek.com" , "cc.chou@mediatek.com" References: <20200724140246.19434-1-stanley.chu@mediatek.com> <1596159018.17247.53.camel@mtkswgap22> 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: <97f1dfb0-41b6-0249-3e82-cae480b0efb6@acm.org> Date: Thu, 30 Jul 2020 21:06:41 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <1596159018.17247.53.camel@mtkswgap22> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020-07-30 18:30, Stanley Chu wrote: > On Mon, 2020-07-27 at 11:18 +0000, Avri Altman wrote: >> Looks good to me. >> But better wait and see if Bart have any further reservations. > > Would you have any further suggestions? Today is the first time that I took a look at ufshcd_abort(). The approach of that function looks wrong to me. This is how I think that a SCSI LLD abort handler should work: (1) Serialize against the completion path (__ufshcd_transfer_req_compl()) such that it cannot happen that the abort handler and the regular completion path both call cmd->scsi_done(cmd) at the same time. I'm not sure whether an existing synchronization object can be used for this purpose or whether a new synchronization object has to be introduced to serialize scsi_done() calls from __ufshcd_transfer_req_compl() and ufshcd_abort(). (2) While holding that synchronization object, check whether the SCSI command is still outstanding. If so, submit a SCSI abort TMR to the device. (3) If the command has been aborted, call scsi_done() and return SUCCESS. If aborting failed and the command is still in progress, return FAILED. An example is available in srp_abort() in drivers/infiniband/ulp/srp/ib_srp.c. Bart.