From patchwork Thu Jul 2 03:34:51 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stanley Chu X-Patchwork-Id: 11637823 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 181266C1 for ; Thu, 2 Jul 2020 03:36:25 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E4B0B207D4 for ; Thu, 2 Jul 2020 03:36:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="RxbjJLN7"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=mediatek.com header.i=@mediatek.com header.b="iN7IUOpd" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E4B0B207D4 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=mediatek.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:Message-ID:Date:Subject:To:From: Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender :Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=XpuCXWLg3mEvWGpEKZzHGWUHnPTn7guTiYeowCoe3s4=; b=RxbjJLN70G+S6HcaQX7ztWC7Dm o4Fn9RlwY+v94xL8ERm/Dg29tNBTTcdL4d2rMXWStVPRJR7b4mZhhCgh38PMniiRppDUlWysThut3 lP1wqyQpkbUrUjbO6/Wqt73kVXUNSCnTR3DP+/ufmQdbM+TiIEHPnhze7yLQeFCmzfRBlbShyZtoX 6Gn+cZfn/hIfW5UuGVTXLlzlBMUcXlgH3+K/D5Rv3UOKgoeNYKLaoNtmS+2HOi6ugCPCiDmW87B3l SFICjun/thvaRI350p7FVpvJp0AdYxAHFogOeGww9IJXa9mbUJLKbefOBWIVCIdU3nQo+gO6cq3x7 V9vVe/pg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jqq08-0006F1-6i; Thu, 02 Jul 2020 03:35:04 +0000 Received: from mailgw01.mediatek.com ([216.200.240.184]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jqq04-0006Dy-Uo; Thu, 02 Jul 2020 03:35:02 +0000 X-UUID: 91fac700349840b7ab8740fd40221b3a-20200701 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Transfer-Encoding:Content-Type:MIME-Version:Message-ID:Date:Subject:CC:To:From; bh=O8tR3m1usHUyKyTLuqtgxgifBOAcJvs4RhW300Axtyc=; b=iN7IUOpdM60nFIddzEpaCCTf0nsW6aiHatJa5NusX4xna0sJey4i8wj+Ne9tc3GToHwsd/blN77dU2okKRmPY8QC54FrudvUU0yhKapvfhL6V7Ysx3PLNpPXs38eZC7ywhxc+O1SbWqTBmpSCA0ihkkDcYwYNr+FtvO373DCCB4=; X-UUID: 91fac700349840b7ab8740fd40221b3a-20200701 Received: from mtkcas67.mediatek.inc [(172.29.193.45)] by mailgw01.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLS) with ESMTP id 83981050; Wed, 01 Jul 2020 19:34:53 -0800 Received: from mtkmbs08n1.mediatek.inc (172.21.101.55) by MTKMBS62N1.mediatek.inc (172.29.193.41) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Wed, 1 Jul 2020 20:34:53 -0700 Received: from MTKCAS06.mediatek.inc (172.21.101.30) by mtkmbs08n1.mediatek.inc (172.21.101.55) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Thu, 2 Jul 2020 11:34:51 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by MTKCAS06.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Thu, 2 Jul 2020 11:34:52 +0800 From: Stanley Chu To: , , , , , Subject: [RFC PATCH v2] scsi: ufs: Quiesce all scsi devices before shutdown Date: Thu, 2 Jul 2020 11:34:51 +0800 Message-ID: <20200702033451.26635-1-stanley.chu@mediatek.com> X-Mailer: git-send-email 2.18.0 MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200701_233501_373542_516C1021 X-CRM114-Status: UNSURE ( 9.90 ) X-CRM114-Notice: Please train this message. X-Spam-Score: -0.2 (/) X-Spam-Report: SpamAssassin version 3.4.4 on merlin.infradead.org summary: Content analysis details: (-0.2 points) pts rule name description ---- ---------------------- -------------------------------------------------- 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.0 SPF_PASS SPF: sender matches SPF record 0.0 MIME_BASE64_TEXT RAW: Message text disguised using base64 encoding -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid 0.0 UNPARSEABLE_RELAY Informational: message has unparseable relay lines X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Stanley Chu , andy.teng@mediatek.com, cc.chou@mediatek.com, chun-hung.wu@mediatek.com, kuohong.wang@mediatek.com, linux-kernel@vger.kernel.org, cang@codeaurora.org, linux-mediatek@lists.infradead.org, peter.wang@mediatek.com, matthias.bgg@gmail.com, beanhuo@micron.com, chaotian.jing@mediatek.com, linux-arm-kernel@lists.infradead.org, asutoshd@codeaurora.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org Currently I/O request could be still submitted to UFS device while UFS is working on shutdown flow. This may lead to racing as below scenarios and finally system may crash due to unclocked register accesses. To fix this kind of issues, specifically quiesce all SCSI devices before UFS shutdown to block all I/O request sending from block layer. Example of racing scenario: While UFS device is runtime-suspended Thread #1: Executing UFS shutdown flow, e.g., ufshcd_suspend(UFS_SHUTDOWN_PM) Thread #2: Executing runtime resume flow triggered by I/O request, e.g., ufshcd_resume(UFS_RUNTIME_PM) This breaks the assumption that UFS PM flows can not be running concurrently and some unexpected racing behavior may happen. Signed-off-by: Stanley Chu --- drivers/scsi/ufs/ufshcd.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 59358bb75014..18da2d64f9fa 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -8599,10 +8599,27 @@ EXPORT_SYMBOL(ufshcd_runtime_idle); int ufshcd_shutdown(struct ufs_hba *hba) { int ret = 0; + struct scsi_target *starget; if (!hba->is_powered) goto out; + /* + * Quiesce all SCSI devices to prevent any non-PM requests sending + * from block layer during and after shutdown. + * + * Here we can not use blk_cleanup_queue() since PM requests + * (with BLK_MQ_REQ_PREEMPT flag) are still required to be sent + * through block layer. Therefore SCSI command queued after the + * scsi_target_quiesce() call returned will block until + * blk_cleanup_queue() is called. + * + * Besides, scsi_target_"un"quiesce (e.g., scsi_target_resume) can + * be ignored since shutdown is one-way flow. + */ + list_for_each_entry(starget, &hba->host->__targets, siblings) + scsi_target_quiesce(starget); + if (ufshcd_is_ufs_dev_poweroff(hba) && ufshcd_is_link_off(hba)) goto out;