From patchwork Thu Feb 11 19:18:28 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Asutosh Das (asd)" X-Patchwork-Id: 12083919 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=-11.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,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 884BEC433E0 for ; Thu, 11 Feb 2021 19:20:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 35D7C64DEC for ; Thu, 11 Feb 2021 19:20:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230138AbhBKTTc (ORCPT ); Thu, 11 Feb 2021 14:19:32 -0500 Received: from labrats.qualcomm.com ([199.106.110.90]:12488 "EHLO labrats.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229742AbhBKTT3 (ORCPT ); Thu, 11 Feb 2021 14:19:29 -0500 IronPort-SDR: yazEGgeAj2g9SnbjH6tVBw2tYi46SQgj9ZXwINNiGU/dIVCSAsXyEReM4v7NBiiPEjRi5mu1ja g3SkZoKbGjbIW5Rm4XSDGhPzFe7esDXzpURjaVA45RlOdjXXCLMQbKMtiN2Hth9Uec0eqEl4eK KQA0zJqVdM06RnzEIH3AvYQEEAyvRaTJrCvCob8IwCtSbb2Ut9owLEd0GhzQokUxUxaL+AMFES eL7VBgpNX34qtyyL7Gkc3w8OZemz97Oa0Z2F163IGF5DcUpNlCuR5BsVwDCurKIWutR42nlLSi ojM= X-IronPort-AV: E=Sophos;i="5.81,171,1610438400"; d="scan'208";a="47741091" Received: from unknown (HELO ironmsg02-sd.qualcomm.com) ([10.53.140.142]) by labrats.qualcomm.com with ESMTP; 11 Feb 2021 11:18:48 -0800 X-QCInternal: smtphost Received: from wsp769891wss.qualcomm.com (HELO stor-presley.qualcomm.com) ([192.168.140.85]) by ironmsg02-sd.qualcomm.com with ESMTP; 11 Feb 2021 11:18:47 -0800 Received: by stor-presley.qualcomm.com (Postfix, from userid 92687) id CB9982191A; Thu, 11 Feb 2021 11:18:47 -0800 (PST) From: Asutosh Das To: cang@codeaurora.org, martin.petersen@oracle.com, linux-scsi@vger.kernel.org Cc: Asutosh Das , linux-arm-msm@vger.kernel.org, stern@rowland.harvard.edu Subject: [RFC PATCH v3 0/1] Enable power management for ufs wlun Date: Thu, 11 Feb 2021 11:18:28 -0800 Message-Id: X-Mailer: git-send-email 2.7.4 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org This patch attempts to fix a deadlock in ufs while sending SSU. Recently, blk_queue_enter() added a check to not process requests if the queue is suspended. That leads to a resume of the associated device which is suspended. In ufs, that device is ufs device wlun and it's parent is ufs_hba. This resume tries to resume ufs device wlun which in turn tries to resume ufs_hba, which is already in the process of suspending, thus causing a deadlock. This patch takes care of: * Suspending the ufs device lun only after all other luns are suspended * Sending SSU during ufs device wlun suspend * Clearing uac for rpmb and ufs device wlun * Not sending commands to the device during host suspend I'm testing it out now, please take a look and let me know. Asutosh Das (1): scsi: ufs: Enable power management for wlun drivers/scsi/ufs/ufshcd.c | 415 +++++++++++++++++++++++++++++++++++++-------- drivers/scsi/ufs/ufshcd.h | 4 + include/trace/events/ufs.h | 20 +++ 3 files changed, 364 insertions(+), 75 deletions(-)