From patchwork Thu Nov 7 09:47:52 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Can Guo X-Patchwork-Id: 11232411 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 B2FA114E5 for ; Thu, 7 Nov 2019 09:48:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8533420656 for ; Thu, 7 Nov 2019 09:48:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="MtTBOOGC"; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="CoHkD6WF" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387756AbfKGJsa (ORCPT ); Thu, 7 Nov 2019 04:48:30 -0500 Received: from smtp.codeaurora.org ([198.145.29.96]:60282 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726866AbfKGJs3 (ORCPT ); Thu, 7 Nov 2019 04:48:29 -0500 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 97CDA60A0A; Thu, 7 Nov 2019 09:48:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1573120107; bh=FtDInhzlNbMYnaah34JKXnQVyTO/o1xFZ/slgp6EYrQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MtTBOOGC3OZ7E99/+3B2moDdUEDx2rKHd3Givhb/dGsdZW9IGWkgzVMUMGKd92K3h Bryny6LkTr30RE7OGY4FmxoL5fDwoh6OKgRrMl1IWSx7mZX/ixFibXTksU1VcQw6Ch llVAbldr+tohfNZ/j7dZ0nY9+FoFI1VStMF/IYDQ= X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on pdx-caf-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.7 required=2.0 tests=ALL_TRUSTED,BAYES_00, DKIM_INVALID,DKIM_SIGNED,SPF_NONE autolearn=no 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@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id 04697602E0; Thu, 7 Nov 2019 09:48:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1573120103; bh=FtDInhzlNbMYnaah34JKXnQVyTO/o1xFZ/slgp6EYrQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CoHkD6WFOFIoWG8COx/lnsD0p8o68PmgRbi32LIt6q2A7Vz+XLs/+IYaxLnpCXYRo oVAEdIXfF6FI2nWq6rYxJM7O6pZEHb/fJG0Pm/haKR0ToCCuE6ooZtY7jLkxQS9WyT mHD1ggpmvI4gbh8Hbd4BbIro5ZTQlKjy1zB5y0xY= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 04697602E0 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=cang@codeaurora.org From: Can Guo To: asutoshd@codeaurora.org, nguyenb@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 , Tomas Winkler , Venkat Gopalakrishnan , Subhash Jadavani , linux-kernel@vger.kernel.org (open list) Subject: [PATCH v2 1/6] scsi: ufs: Flush exception event before suspend Date: Thu, 7 Nov 2019 01:47:52 -0800 Message-Id: <1573120078-15547-2-git-send-email-cang@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1573120078-15547-1-git-send-email-cang@codeaurora.org> References: <1573120078-15547-1-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 --- 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;