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=-9.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 DBBF2C33CAA for ; Thu, 23 Jan 2020 06:12:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id ABBDF24655 for ; Thu, 23 Jan 2020 06:12:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="NlyuTrzZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726103AbgAWGMp (ORCPT ); Thu, 23 Jan 2020 01:12:45 -0500 Received: from mail25.static.mailgun.info ([104.130.122.25]:42451 "EHLO mail25.static.mailgun.info" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725818AbgAWGMp (ORCPT ); Thu, 23 Jan 2020 01:12:45 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1579759964; h=References: In-Reply-To: Message-Id: Date: Subject: Cc: To: From: Sender; bh=9S0QIlbYmQAb+fbkT7yD3PV4Zf5YseEdwAjssYu+PQ8=; b=NlyuTrzZfMfyrczXjiAgD94Y4TZBr8LLpRkQZx/PjThOBL5EGkehIRR3n44GqyT2ecp/dSGh WNK9bzcq0MUVvllh6VZQMsjM/0b62QqcKGN6/fu5t1AnMkiay5hMiZ09+0rnwW40YEB91vUg Cq5TitLs80zLhtUmnDEK5k5Tzis= X-Mailgun-Sending-Ip: 104.130.122.25 X-Mailgun-Sid: WyI0MWYwYSIsICJsaW51eC1rZXJuZWxAdmdlci5rZXJuZWwub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by mxa.mailgun.org with ESMTP id 5e29395b.7fb056a165a8-smtp-out-n02; Thu, 23 Jan 2020 06:12:43 -0000 (UTC) Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 6427EC447B1; Thu, 23 Jan 2020 06:12:43 +0000 (UTC) Received: from pacamara-linux.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: cang) by smtp.codeaurora.org (Postfix) with ESMTPSA id 9E777C447A5; Thu, 23 Jan 2020 06:12:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 9E777C447A5 Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=none smtp.mailfrom=cang@codeaurora.org From: Can Guo To: asutoshd@codeaurora.org, nguyenb@codeaurora.org, hongwus@codeaurora.org, rnayak@codeaurora.org, linux-scsi@vger.kernel.org, kernel-team@android.com, saravanak@google.com, salyzyn@google.com, cang@codeaurora.org Cc: Sayali Lokhande , Alim Akhtar , Avri Altman , Pedro Sousa , "James E.J. Bottomley" , "Martin K. Petersen" , Stanley Chu , Bean Huo , Venkat Gopalakrishnan , Tomas Winkler , linux-kernel@vger.kernel.org (open list) Subject: [PATCH v3 1/8] scsi: ufs: Flush exception event before suspend Date: Wed, 22 Jan 2020 22:12:18 -0800 Message-Id: <1579759946-5448-2-git-send-email-cang@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1579759946-5448-1-git-send-email-cang@codeaurora.org> References: <1579759946-5448-1-git-send-email-cang@codeaurora.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Sayali Lokhande Exception event can be raised by the device when system suspend is in progress. This will result in unclocked register access in exception event handler as clocks will be turned off during suspend. This change makes sure to flush exception event handler work in suspend before disabling clocks to avoid unclocked register access issue. Signed-off-by: Sayali Lokhande Signed-off-by: Asutosh Das Signed-off-by: Can Guo --- drivers/scsi/ufs/ufshcd.c | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 1201578..c2de29f 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -4760,8 +4760,15 @@ static void ufshcd_slave_destroy(struct scsi_device *sdev) * UFS device needs urgent BKOPs. */ if (!hba->pm_op_in_progress && - ufshcd_is_exception_event(lrbp->ucd_rsp_ptr)) - schedule_work(&hba->eeh_work); + ufshcd_is_exception_event(lrbp->ucd_rsp_ptr)) { + /* + * Prevent suspend once eeh_work is scheduled + * to avoid deadlock between ufshcd_suspend + * and exception event handler. + */ + if (schedule_work(&hba->eeh_work)) + pm_runtime_get_noresume(hba->dev); + } break; case UPIU_TRANSACTION_REJECT_UPIU: /* TODO: handle Reject UPIU Response */ @@ -5215,7 +5222,14 @@ static void ufshcd_exception_event_handler(struct work_struct *work) out: scsi_unblock_requests(hba->host); - pm_runtime_put_sync(hba->dev); + /* + * pm_runtime_get_noresume is called while scheduling + * eeh_work to avoid suspend racing with exception work. + * Hence decrement usage counter using pm_runtime_put_noidle + * to allow suspend on completion of exception event handler. + */ + pm_runtime_put_noidle(hba->dev); + pm_runtime_put(hba->dev); return; } @@ -7901,6 +7915,7 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op) goto enable_gating; } + flush_work(&hba->eeh_work); ret = ufshcd_link_state_transition(hba, req_link_state, 1); if (ret) goto set_dev_active; -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project