From patchwork Thu Feb 6 06:56:44 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Can Guo X-Patchwork-Id: 11367683 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 8AAE81398 for ; Thu, 6 Feb 2020 06:57:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 69B26214AF for ; Thu, 6 Feb 2020 06:57:09 +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="Yad50AMf" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727946AbgBFG5J (ORCPT ); Thu, 6 Feb 2020 01:57:09 -0500 Received: from mail25.static.mailgun.info ([104.130.122.25]:63714 "EHLO mail25.static.mailgun.info" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727843AbgBFG5J (ORCPT ); Thu, 6 Feb 2020 01:57:09 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1580972228; h=References: In-Reply-To: Message-Id: Date: Subject: Cc: To: From: Sender; bh=qPkoBZcjFDDffVZqOjSoc0Prt/FQJ0KkDvb0IVj8YME=; b=Yad50AMfY2TsfFagIyME/42mkcN3ITt5kbxiGgrvWqS5arGnlHbAM7X084yFjuj0j9rXVO23 f53ayvg3fjy6AKwX3G43lQGNxyCD9KIzdEll+iQGMKxku18C89hYeo3/Z/bC3bVC3rtybhOR t6T9QUM5Q21vVoZQ6M/SQkQgvog= X-Mailgun-Sending-Ip: 104.130.122.25 X-Mailgun-Sid: WyJlNmU5NiIsICJsaW51eC1zY3NpQHZnZXIua2VybmVsLm9yZyIsICJiZTllNGEiXQ== 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 5e3bb8c2.7f6a06bc5570-smtp-out-n03; Thu, 06 Feb 2020 06:57:06 -0000 (UTC) Received: by smtp.codeaurora.org (Postfix, from userid 1001) id D0E38C4479C; Thu, 6 Feb 2020 06:57:04 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-caf-mail-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=2.0 tests=ALL_TRUSTED,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.0 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 3B1E4C433CB; Thu, 6 Feb 2020 06:57:02 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 3B1E4C433CB 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 , "James E.J. Bottomley" , "Martin K. Petersen" , Bean Huo , Stanley Chu , Bart Van Assche , Venkat Gopalakrishnan , Tomas Winkler , linux-kernel@vger.kernel.org (open list) Subject: [PATCH 1/8] scsi: ufs: Flush exception event before suspend Date: Wed, 5 Feb 2020 22:56:44 -0800 Message-Id: <1580972212-29881-2-git-send-email-cang@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1580972212-29881-1-git-send-email-cang@codeaurora.org> References: <1580972212-29881-1-git-send-email-cang@codeaurora.org> Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@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 Reviewed-by: Bean Huo diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index abd0e6b..10dbc0c 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -4730,8 +4730,15 @@ 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) && + schedule_work(&hba->eeh_work)) { + /* + * Prevent suspend once eeh_work is scheduled + * to avoid deadlock between ufshcd_suspend + * and exception event handler. + */ + pm_runtime_get_noresume(hba->dev); + } break; case UPIU_TRANSACTION_REJECT_UPIU: /* TODO: handle Reject UPIU Response */ @@ -5184,7 +5191,14 @@ static void ufshcd_exception_event_handler(struct work_struct *work) out: ufshcd_scsi_unblock_requests(hba); - 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; } @@ -7924,6 +7938,7 @@ 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;