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=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 D9679C33CAA for ; Thu, 23 Jan 2020 07:26:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AA258217F4 for ; Thu, 23 Jan 2020 07:26:05 +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="vnr9wTWw" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726442AbgAWH0E (ORCPT ); Thu, 23 Jan 2020 02:26:04 -0500 Received: from mail26.static.mailgun.info ([104.130.122.26]:23129 "EHLO mail26.static.mailgun.info" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726054AbgAWH0D (ORCPT ); Thu, 23 Jan 2020 02:26:03 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1579764363; h=References: In-Reply-To: Message-Id: Date: Subject: Cc: To: From: Sender; bh=9S0QIlbYmQAb+fbkT7yD3PV4Zf5YseEdwAjssYu+PQ8=; b=vnr9wTWw2x2Veo4SM1099Zb4UQdHa1hU6RcceKNILV7zvbtEja1UaX36JHlbWs5TBF4f3o5c 7O7AFLmr8TVljm7+KhrAAIW0lqT6l2KT0Yw+/KnQCKcl5Sst/wa1h+XMOjToAoHgFN0rtAvX LHD6+KXvrvovmyVTvQFUmvwT7WQ= X-Mailgun-Sending-Ip: 104.130.122.26 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 5e294a8a.7fd2376666f8-smtp-out-n01; Thu, 23 Jan 2020 07:26:02 -0000 (UTC) Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 1B3C1C447A5; Thu, 23 Jan 2020 07:26:02 +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 666D0C43383; Thu, 23 Jan 2020 07:26:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 666D0C43383 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 v4 1/8] scsi: ufs: Flush exception event before suspend Date: Wed, 22 Jan 2020 23:25:42 -0800 Message-Id: <1579764349-15578-2-git-send-email-cang@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1579764349-15578-1-git-send-email-cang@codeaurora.org> References: <1579764349-15578-1-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