From patchwork Tue Aug 1 15:21:30 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Brian King X-Patchwork-Id: 9874835 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id F34E86038F for ; Tue, 1 Aug 2017 15:21:39 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E2D4128652 for ; Tue, 1 Aug 2017 15:21:39 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D7869286C6; Tue, 1 Aug 2017 15:21:39 +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=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable 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 6E578286CB for ; Tue, 1 Aug 2017 15:21:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751773AbdHAPVi (ORCPT ); Tue, 1 Aug 2017 11:21:38 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:42901 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751701AbdHAPVg (ORCPT ); Tue, 1 Aug 2017 11:21:36 -0400 Received: from pps.filterd (m0098420.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v71FJUrV039602 for ; Tue, 1 Aug 2017 11:21:35 -0400 Received: from e38.co.us.ibm.com (e38.co.us.ibm.com [32.97.110.159]) by mx0b-001b2d01.pphosted.com with ESMTP id 2c2tj2dm01-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 01 Aug 2017 11:21:35 -0400 Received: from localhost by e38.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Tue, 1 Aug 2017 09:21:31 -0600 Received: from b03ledav005.gho.boulder.ibm.com (b03ledav005.gho.boulder.ibm.com [9.17.130.236]) by b03cxnp08027.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v71FLVxk65536082; Tue, 1 Aug 2017 08:21:31 -0700 Received: from b03ledav005.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 2AF05BE042; Tue, 1 Aug 2017 09:21:31 -0600 (MDT) Received: from [9.10.86.49] (unknown [9.10.86.49]) by b03ledav005.gho.boulder.ibm.com (Postfix) with ESMTP id 86758BE044; Tue, 1 Aug 2017 09:21:30 -0600 (MDT) Subject: [PATCH] ipr: Fix scsi-mq lockdep issue To: linux-scsi Cc: Michael Ellerman , Jens Axboe , "linux-kernel@vger.kernel.org" , "linux-block@vger.kernel.org" , Bart Van Assche , "linuxppc-dev@lists.ozlabs.org" , "James E.J. Bottomley" , Wendy Xiong References: <87a83qfosu.fsf@concordia.ellerman.id.au> <073ed79c-11ce-e86c-a905-91fd28675d47@kernel.dk> <1501166846.2516.1.camel@wdc.com> <5b85a365-faa1-3987-9b6b-270399c30686@kernel.dk> <87lgn9dqx3.fsf@concordia.ellerman.id.au> <92379297-9667-ae52-b05c-6c8a0ce4751c@kernel.dk> <5dcfe3ac-50c7-86a6-e571-fe5a1c1dc316@linux.vnet.ibm.com> <87379c6cfh.fsf@concordia.ellerman.id.au> <87a83ju6av.fsf@concordia.ellerman.id.au> From: Brian King Date: Tue, 1 Aug 2017 10:21:30 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.0 MIME-Version: 1.0 In-Reply-To: <87a83ju6av.fsf@concordia.ellerman.id.au> Content-Language: en-US X-TM-AS-GCONF: 00 x-cbid: 17080115-0028-0000-0000-0000081F51DD X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00007465; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000215; SDB=6.00896050; UDB=6.00448214; IPR=6.00676238; BA=6.00005506; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00016482; XFM=3.00000015; UTC=2017-08-01 15:21:33 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17080115-0029-0000-0000-000036F11C7D Message-Id: <6d2bbcc8-3f4b-9b41-45b2-160f4817e439@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-08-01_08:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=2 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1706020000 definitions=main-1708010252 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 Fixes the following lockdep warning that can occur when scsi-mq is enabled with ipr due to ipr calling scsi_unblock_requests from irq context. The fix is to move the call to scsi_unblock_requests to ipr's existing workqueue. stack backtrace: CPU: 28 PID: 0 Comm: swapper/28 Not tainted 4.13.0-rc2-gcc6x-gf74c89b #1 Call Trace: [c000001fffe97550] [c000000000b50818] dump_stack+0xe8/0x160 (unreliable) [c000001fffe97590] [c0000000001586d0] print_usage_bug+0x2d0/0x390 [c000001fffe97640] [c000000000158f34] mark_lock+0x7a4/0x8e0 [c000001fffe976f0] [c00000000015a000] __lock_acquire+0x6a0/0x1a70 [c000001fffe97860] [c00000000015befc] lock_acquire+0xec/0x2e0 [c000001fffe97930] [c000000000b71514] _raw_spin_lock+0x44/0x70 [c000001fffe97960] [c0000000005b60f4] blk_mq_sched_dispatch_requests+0xa4/0x2a0 [c000001fffe979c0] [c0000000005acac0] __blk_mq_run_hw_queue+0x100/0x2c0 [c000001fffe97a00] [c0000000005ad478] __blk_mq_delay_run_hw_queue+0x118/0x130 [c000001fffe97a40] [c0000000005ad61c] blk_mq_start_hw_queues+0x6c/0xa0 [c000001fffe97a80] [c000000000797aac] scsi_kick_queue+0x2c/0x60 [c000001fffe97aa0] [c000000000797cf0] scsi_run_queue+0x210/0x360 [c000001fffe97b10] [c00000000079b888] scsi_run_host_queues+0x48/0x80 [c000001fffe97b40] [c0000000007b6090] ipr_ioa_bringdown_done+0x70/0x1e0 [c000001fffe97bc0] [c0000000007bc860] ipr_reset_ioa_job+0x80/0xf0 [c000001fffe97bf0] [c0000000007b4d50] ipr_reset_timer_done+0xd0/0x100 [c000001fffe97c30] [c0000000001937bc] call_timer_fn+0xdc/0x4b0 [c000001fffe97cf0] [c000000000193d08] expire_timers+0x178/0x330 [c000001fffe97d60] [c0000000001940c8] run_timer_softirq+0xb8/0x120 [c000001fffe97de0] [c000000000b726a8] __do_softirq+0x168/0x6d8 [c000001fffe97ef0] [c0000000000df2c8] irq_exit+0x108/0x150 [c000001fffe97f10] [c000000000017bf4] __do_irq+0x2a4/0x4a0 [c000001fffe97f90] [c00000000002da50] call_do_irq+0x14/0x24 [c0000007fad93aa0] [c000000000017e8c] do_IRQ+0x9c/0x140 [c0000007fad93af0] [c000000000008b98] hardware_interrupt_common+0x138/0x140 Reported-by: Michael Ellerman Signed-off-by: Brian King Index: linux-2.6.git/drivers/scsi/ipr.c =================================================================== --- linux-2.6.git.orig/drivers/scsi/ipr.c +++ linux-2.6.git/drivers/scsi/ipr.c @@ -3351,6 +3351,16 @@ static void ipr_worker_thread(struct wor return; } + if (ioa_cfg->scsi_unblock) { + ioa_cfg->scsi_unblock = 0; + ioa_cfg->scsi_blocked = 0; + spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags); + scsi_unblock_requests(ioa_cfg->host); + spin_lock_irqsave(ioa_cfg->host->host_lock, lock_flags); + if (ioa_cfg->scsi_blocked) + scsi_block_requests(ioa_cfg->host); + } + if (!ioa_cfg->scan_enabled) { spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags); return; @@ -7211,9 +7221,8 @@ static int ipr_ioa_bringdown_done(struct ENTER; if (!ioa_cfg->hrrq[IPR_INIT_HRRQ].removing_ioa) { ipr_trace; - spin_unlock_irq(ioa_cfg->host->host_lock); - scsi_unblock_requests(ioa_cfg->host); - spin_lock_irq(ioa_cfg->host->host_lock); + ioa_cfg->scsi_unblock = 1; + schedule_work(&ioa_cfg->work_q); } ioa_cfg->in_reset_reload = 0; @@ -7287,13 +7296,7 @@ static int ipr_ioa_reset_done(struct ipr list_add_tail(&ipr_cmd->queue, &ipr_cmd->hrrq->hrrq_free_q); wake_up_all(&ioa_cfg->reset_wait_q); - spin_unlock(ioa_cfg->host->host_lock); - scsi_unblock_requests(ioa_cfg->host); - spin_lock(ioa_cfg->host->host_lock); - - if (!ioa_cfg->hrrq[IPR_INIT_HRRQ].allow_cmds) - scsi_block_requests(ioa_cfg->host); - + ioa_cfg->scsi_unblock = 1; schedule_work(&ioa_cfg->work_q); LEAVE; return IPR_RC_JOB_RETURN; @@ -9249,8 +9252,11 @@ static void _ipr_initiate_ioa_reset(stru spin_unlock(&ioa_cfg->hrrq[i]._lock); } wmb(); - if (!ioa_cfg->hrrq[IPR_INIT_HRRQ].removing_ioa) + if (!ioa_cfg->hrrq[IPR_INIT_HRRQ].removing_ioa) { + ioa_cfg->scsi_unblock = 0; + ioa_cfg->scsi_blocked = 1; scsi_block_requests(ioa_cfg->host); + } ipr_cmd = ipr_get_free_ipr_cmnd(ioa_cfg); ioa_cfg->reset_cmd = ipr_cmd; @@ -9306,9 +9312,8 @@ static void ipr_initiate_ioa_reset(struc wake_up_all(&ioa_cfg->reset_wait_q); if (!ioa_cfg->hrrq[IPR_INIT_HRRQ].removing_ioa) { - spin_unlock_irq(ioa_cfg->host->host_lock); - scsi_unblock_requests(ioa_cfg->host); - spin_lock_irq(ioa_cfg->host->host_lock); + ioa_cfg->scsi_unblock = 1; + schedule_work(&ioa_cfg->work_q); } return; } else { Index: linux-2.6.git/drivers/scsi/ipr.h =================================================================== --- linux-2.6.git.orig/drivers/scsi/ipr.h +++ linux-2.6.git/drivers/scsi/ipr.h @@ -1488,6 +1488,8 @@ struct ipr_ioa_cfg { u8 cfg_locked:1; u8 clear_isr:1; u8 probe_done:1; + u8 scsi_unblock:1; + u8 scsi_blocked:1; u8 revid;