From patchwork Thu Aug 2 17:44:42 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bart Van Assche X-Patchwork-Id: 10554007 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 43136139A for ; Thu, 2 Aug 2018 17:44:46 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3236A2C3C6 for ; Thu, 2 Aug 2018 17:44:46 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 23C812C3DE; Thu, 2 Aug 2018 17:44:46 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI,T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8D62D2C3C6 for ; Thu, 2 Aug 2018 17:44:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387562AbeHBTgw (ORCPT ); Thu, 2 Aug 2018 15:36:52 -0400 Received: from esa5.hgst.iphmx.com ([216.71.153.144]:58397 "EHLO esa5.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387422AbeHBTgw (ORCPT ); Thu, 2 Aug 2018 15:36:52 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=wdc.com; i=@wdc.com; q=dns/txt; s=dkim.wdc.com; t=1533231884; x=1564767884; h=from:to:cc:subject:date:message-id; bh=zX5JgZPpaReDBAU41OV+K/j5lV3EaWA0ASyDaa4fZdU=; b=K4uvpVobzr9UVAn9tArdqyrNKdsS5ZvaPQyIMiIJqAvJ9wXfvq3rv+ey bSSDoXBO7ORwI/T7qK5DQYpM1KZfjVFT2W40Gxo1TV3AMj6Z84on0mboY hK90r7JAJ/k0O5ByBvVwRlQMUadihWtuQZa4EVq0ZKJ6X9FM5qxjH6cWX oJFwMzxmgH49m1e1oonIRgbQkujEXJrd6HLtn1rY/4VTOtYYMf7itEPyo emfvJ8v9v5LMpl96JNUnISbkziCn5hybgAGuyUnT+aA7jQdk1EdAkETq0 Bw5WmXrFp9tSvbqswcDmphdudZuPDCIZtApuE+aeRwPwNjFDh2STP5z1/ A==; X-IronPort-AV: E=Sophos;i="5.51,436,1526313600"; d="scan'208";a="86969624" Received: from uls-op-cesaip01.wdc.com (HELO uls-op-cesaep01.wdc.com) ([199.255.45.14]) by ob1.hgst.iphmx.com with ESMTP; 03 Aug 2018 01:44:43 +0800 Received: from uls-op-cesaip01.wdc.com ([10.248.3.36]) by uls-op-cesaep01.wdc.com with ESMTP; 02 Aug 2018 10:33:06 -0700 Received: from thinkpad-bart.sdcorp.global.sandisk.com ([10.111.67.248]) by uls-op-cesaip01.wdc.com with ESMTP; 02 Aug 2018 10:44:44 -0700 From: Bart Van Assche To: "Martin K . Petersen" , "James E . J . Bottomley" Cc: linux-scsi@vger.kernel.org, Bart Van Assche , Maurizio Lombardi , Johannes Thumshirn , Alan Stern , stable@vger.kernel.org Subject: [PATCH] sr: Avoid that opening a CD-ROM hangs with runtime power management enabled Date: Thu, 2 Aug 2018 10:44:42 -0700 Message-Id: <20180802174442.7310-1-bart.vanassche@wdc.com> X-Mailer: git-send-email 2.18.0 Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Surround scsi_execute() calls with scsi_autopm_get_device() and scsi_autopm_put_device(). Note: removing sr_mutex protection from the scsi_cd_get() and scsi_cd_put() calls is safe because the purpose of sr_mutex is to serialize cdrom_*() calls. This patch avoids that complaints similar to the following appear in the kernel log if runtime power management is enabled: INFO: task systemd-udevd:650 blocked for more than 120 seconds. Not tainted 4.18.0-rc7-dbg+ #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. systemd-udevd D28176 650 513 0x00000104 Call Trace: __schedule+0x444/0xfe0 schedule+0x4e/0xe0 schedule_preempt_disabled+0x18/0x30 __mutex_lock+0x41c/0xc70 mutex_lock_nested+0x1b/0x20 __blkdev_get+0x106/0x970 blkdev_get+0x22c/0x5a0 blkdev_open+0xe9/0x100 do_dentry_open.isra.19+0x33e/0x570 vfs_open+0x7c/0xd0 path_openat+0x6e3/0x1120 do_filp_open+0x11c/0x1c0 do_sys_open+0x208/0x2d0 __x64_sys_openat+0x59/0x70 do_syscall_64+0x77/0x230 entry_SYSCALL_64_after_hwframe+0x49/0xbe Signed-off-by: Bart Van Assche Cc: Maurizio Lombardi Cc: Johannes Thumshirn Cc: Alan Stern Cc: Tested-by: Johannes Thumshirn Reviewed-by: Johannes Thumshirn --- drivers/scsi/sr.c | 29 +++++++++++++++++++++-------- 1 file changed, 21 insertions(+), 8 deletions(-) diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c index 3f3cb72e0c0c..d0389b20574d 100644 --- a/drivers/scsi/sr.c +++ b/drivers/scsi/sr.c @@ -523,18 +523,26 @@ static int sr_init_command(struct scsi_cmnd *SCpnt) static int sr_block_open(struct block_device *bdev, fmode_t mode) { struct scsi_cd *cd; + struct scsi_device *sdev; int ret = -ENXIO; + cd = scsi_cd_get(bdev->bd_disk); + if (!cd) + goto out; + + sdev = cd->device; + scsi_autopm_get_device(sdev); check_disk_change(bdev); mutex_lock(&sr_mutex); - cd = scsi_cd_get(bdev->bd_disk); - if (cd) { - ret = cdrom_open(&cd->cdi, bdev, mode); - if (ret) - scsi_cd_put(cd); - } + ret = cdrom_open(&cd->cdi, bdev, mode); mutex_unlock(&sr_mutex); + + scsi_autopm_put_device(sdev); + if (ret) + scsi_cd_put(cd); + +out: return ret; } @@ -562,6 +570,8 @@ static int sr_block_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd, if (ret) goto out; + scsi_autopm_get_device(sdev); + /* * Send SCSI addressing ioctls directly to mid level, send other * ioctls to cdrom/block level. @@ -570,15 +580,18 @@ static int sr_block_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd, case SCSI_IOCTL_GET_IDLUN: case SCSI_IOCTL_GET_BUS_NUMBER: ret = scsi_ioctl(sdev, cmd, argp); - goto out; + goto put; } ret = cdrom_ioctl(&cd->cdi, bdev, mode, cmd, arg); if (ret != -ENOSYS) - goto out; + goto put; ret = scsi_ioctl(sdev, cmd, argp); +put: + scsi_autopm_put_device(sdev); + out: mutex_unlock(&sr_mutex); return ret;