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=-18.0 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=ham 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 32A4DC433DB for ; Fri, 1 Jan 2021 16:06:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F1DBD221FE for ; Fri, 1 Jan 2021 16:06:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727241AbhAAQFr (ORCPT ); Fri, 1 Jan 2021 11:05:47 -0500 Received: from mail-pl1-f170.google.com ([209.85.214.170]:34069 "EHLO mail-pl1-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727181AbhAAQFq (ORCPT ); Fri, 1 Jan 2021 11:05:46 -0500 Received: by mail-pl1-f170.google.com with SMTP id t6so11230191plq.1; Fri, 01 Jan 2021 08:05:31 -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:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=C02k2lVQV4BY4JNeZeCIxYmhRctA7lTjARTl+uthnK4=; b=FMTTJYpLyPLE5w+DeL40lEngi7H6jgsZwrmAC4FlXeFDqIUpKZzBfj106cfQdLdtZN 7i0IjgNHhY2njfAJ1DWGzNGYt8qPXRbsG4CsF/DzMzh7A+v3vrKQTPCnTYPGdhDZtEsB NABBbiTs6FiNWO5VUmtdtcupr7ltEEnH1rpGPJUa3q/qMWhN+KTH1csu6ClpaOI53xlu 9lqcsgfInksnz44L7iCRTkQTpXn6Z/ywLv9JeL4CcQQBG1HuaHVjquTJ44BbHpXkqZFy U5VPA83sBOy+XWEA+/z50UegRHmaJkAfKabdEyoS3bmi8lOw9ZturnPJU9gSZNBI6Eo7 H/hA== X-Gm-Message-State: AOAM5305Nd6tKnEKtFDGHbZiutfwPwwr9vVZPX/6VFr7Fz/PG8vtL5+P TXV+v/7cFx8a3ZKsZuUB2ATnVajau4I= X-Google-Smtp-Source: ABdhPJz4tP4UcpAY+7kHazDsyvutQznO68u3nakYQCZnitmwaJssTbyMK6LvJMIWHpZnlAfa8FyFew== X-Received: by 2002:a17:902:b7c3:b029:da:76bc:2aa9 with SMTP id v3-20020a170902b7c3b02900da76bc2aa9mr62271011plz.21.1609517105100; Fri, 01 Jan 2021 08:05:05 -0800 (PST) Received: from [192.168.3.217] (c-73-241-217-19.hsd1.ca.comcast.net. [73.241.217.19]) by smtp.gmail.com with ESMTPSA id js9sm17588351pjb.2.2021.01.01.08.05.02 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 01 Jan 2021 08:05:03 -0800 (PST) Subject: Re: [PATCH v2 1/2] scsi: ufs: Fix a possible NULL pointer issue To: Can Guo , asutoshd@codeaurora.org, nguyenb@codeaurora.org, hongwus@codeaurora.org, ziqichen@codeaurora.org, rnayak@codeaurora.org, linux-scsi@vger.kernel.org, kernel-team@android.com, saravanak@google.com, salyzyn@google.com Cc: Alim Akhtar , Avri Altman , "James E.J. Bottomley" , "Martin K. Petersen" , Stanley Chu , Bean Huo , open list References: <1609479893-8889-1-git-send-email-cang@codeaurora.org> <1609479893-8889-2-git-send-email-cang@codeaurora.org> From: Bart Van Assche Message-ID: <7cff30c3-6df8-7b8c-0f5b-a95980b8f706@acm.org> Date: Fri, 1 Jan 2021 08:05:01 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 In-Reply-To: <1609479893-8889-2-git-send-email-cang@codeaurora.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/31/20 9:44 PM, Can Guo wrote: > During system resume/suspend, hba could be NULL. In this case, do not touch > eh_sem. > > Fixes: 88a92d6ae4fe ("scsi: ufs: Serialize eh_work with system PM events and async scan") > > Signed-off-by: Can Guo > --- > drivers/scsi/ufs/ufshcd.c | 9 +++++---- > 1 file changed, 5 insertions(+), 4 deletions(-) > > diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c > index e221add..34e2541 100644 > --- a/drivers/scsi/ufs/ufshcd.c > +++ b/drivers/scsi/ufs/ufshcd.c > @@ -8896,8 +8896,11 @@ int ufshcd_system_suspend(struct ufs_hba *hba) > int ret = 0; > ktime_t start = ktime_get(); > > + if (!hba) > + return 0; > + > down(&hba->eh_sem); > - if (!hba || !hba->is_powered) > + if (!hba->is_powered) > return 0; > > if ((ufs_get_pm_lvl_to_dev_pwr_mode(hba->spm_lvl) == > @@ -8945,10 +8948,8 @@ int ufshcd_system_resume(struct ufs_hba *hba) > int ret = 0; > ktime_t start = ktime_get(); > > - if (!hba) { > - up(&hba->eh_sem); > + if (!hba) > return -EINVAL; > - } > > if (!hba->is_powered || pm_runtime_suspended(hba->dev)) > /* Hi Can, How can ufshcd_system_suspend() or ufshcd_system_resume() be called with a NULL argument? In ufshcd_pci_probe() I see that pci_set_drvdata() is called before pm_runtime_allow(). ufshcd_pci_remove() calls pm_runtime_forbid(). Thanks, Bart.