From mboxrd@z Thu Jan 1 00:00:00 1970 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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 E1EB2ECDE43 for ; Thu, 18 Oct 2018 17:57:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9F8BA21479 for ; Thu, 18 Oct 2018 17:57:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="J+jyEg6B" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9F8BA21479 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728948AbeJSB77 (ORCPT ); Thu, 18 Oct 2018 21:59:59 -0400 Received: from mail.kernel.org ([198.145.29.99]:47626 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727605AbeJSB76 (ORCPT ); Thu, 18 Oct 2018 21:59:58 -0400 Received: from localhost (ip-213-127-77-176.ip.prioritytelecom.net [213.127.77.176]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 1C17721479; Thu, 18 Oct 2018 17:57:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1539885473; bh=f+tazmJ8vhj0HxTSlr9kgdOV4vNnUBJUJc6lbI335AE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=J+jyEg6Bi11vDS/qBZkkHaLYTRCGc582WaJL9dMpHUcYskpL+rJgWa1ZdXE7DhvaD vw/qfQVOyGYV5FohOBsoxJRyt7qayLuYHi6oH7XoCC2RLa/Bf0AdD3XSxOcv3X+55T wjoGbPvCpNAWuT0LKT8Q8B0zDMZg7l2yHmpO6+QE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Wen Xiong , Brian King , "Martin K. Petersen" , Sasha Levin Subject: [PATCH 4.18 34/53] scsi: ipr: System hung while dlpar adding primary ipr adapter back Date: Thu, 18 Oct 2018 19:54:27 +0200 Message-Id: <20181018175422.668086312@linuxfoundation.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181018175416.561567978@linuxfoundation.org> References: <20181018175416.561567978@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Wen Xiong [ Upstream commit 318ddb34b2052f838aa243d07173e2badf3e630e ] While dlpar adding primary ipr adapter back, driver goes through adapter initialization then schedule ipr_worker_thread to start te disk scan by dropping the host lock, calling scsi_add_device. Then get the adapter reset request again, so driver does scsi_block_requests, this will cause the scsi_add_device get hung until we unblock. But we can't run ipr_worker_thread to do the unblock because its stuck in scsi_add_device. This patch fixes the issue. [mkp: typo and whitespace fixes] Signed-off-by: Wen Xiong Acked-by: Brian King Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/scsi/ipr.c | 106 ++++++++++++++++++++++++++++++----------------------- drivers/scsi/ipr.h | 1 2 files changed, 62 insertions(+), 45 deletions(-) --- a/drivers/scsi/ipr.c +++ b/drivers/scsi/ipr.c @@ -3310,6 +3310,65 @@ static void ipr_release_dump(struct kref LEAVE; } +static void ipr_add_remove_thread(struct work_struct *work) +{ + unsigned long lock_flags; + struct ipr_resource_entry *res; + struct scsi_device *sdev; + struct ipr_ioa_cfg *ioa_cfg = + container_of(work, struct ipr_ioa_cfg, scsi_add_work_q); + u8 bus, target, lun; + int did_work; + + ENTER; + spin_lock_irqsave(ioa_cfg->host->host_lock, lock_flags); + +restart: + do { + did_work = 0; + if (!ioa_cfg->hrrq[IPR_INIT_HRRQ].allow_cmds) { + spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags); + return; + } + + list_for_each_entry(res, &ioa_cfg->used_res_q, queue) { + if (res->del_from_ml && res->sdev) { + did_work = 1; + sdev = res->sdev; + if (!scsi_device_get(sdev)) { + if (!res->add_to_ml) + list_move_tail(&res->queue, &ioa_cfg->free_res_q); + else + res->del_from_ml = 0; + spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags); + scsi_remove_device(sdev); + scsi_device_put(sdev); + spin_lock_irqsave(ioa_cfg->host->host_lock, lock_flags); + } + break; + } + } + } while (did_work); + + list_for_each_entry(res, &ioa_cfg->used_res_q, queue) { + if (res->add_to_ml) { + bus = res->bus; + target = res->target; + lun = res->lun; + res->add_to_ml = 0; + spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags); + scsi_add_device(ioa_cfg->host, bus, target, lun); + spin_lock_irqsave(ioa_cfg->host->host_lock, lock_flags); + goto restart; + } + } + + ioa_cfg->scan_done = 1; + spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags); + kobject_uevent(&ioa_cfg->host->shost_dev.kobj, KOBJ_CHANGE); + LEAVE; +} + /** * ipr_worker_thread - Worker thread * @work: ioa config struct @@ -3324,13 +3383,9 @@ static void ipr_release_dump(struct kref static void ipr_worker_thread(struct work_struct *work) { unsigned long lock_flags; - struct ipr_resource_entry *res; - struct scsi_device *sdev; struct ipr_dump *dump; struct ipr_ioa_cfg *ioa_cfg = container_of(work, struct ipr_ioa_cfg, work_q); - u8 bus, target, lun; - int did_work; ENTER; spin_lock_irqsave(ioa_cfg->host->host_lock, lock_flags); @@ -3368,49 +3423,9 @@ static void ipr_worker_thread(struct wor return; } -restart: - do { - did_work = 0; - if (!ioa_cfg->hrrq[IPR_INIT_HRRQ].allow_cmds) { - spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags); - return; - } + schedule_work(&ioa_cfg->scsi_add_work_q); - list_for_each_entry(res, &ioa_cfg->used_res_q, queue) { - if (res->del_from_ml && res->sdev) { - did_work = 1; - sdev = res->sdev; - if (!scsi_device_get(sdev)) { - if (!res->add_to_ml) - list_move_tail(&res->queue, &ioa_cfg->free_res_q); - else - res->del_from_ml = 0; - spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags); - scsi_remove_device(sdev); - scsi_device_put(sdev); - spin_lock_irqsave(ioa_cfg->host->host_lock, lock_flags); - } - break; - } - } - } while (did_work); - - list_for_each_entry(res, &ioa_cfg->used_res_q, queue) { - if (res->add_to_ml) { - bus = res->bus; - target = res->target; - lun = res->lun; - res->add_to_ml = 0; - spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags); - scsi_add_device(ioa_cfg->host, bus, target, lun); - spin_lock_irqsave(ioa_cfg->host->host_lock, lock_flags); - goto restart; - } - } - - ioa_cfg->scan_done = 1; spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags); - kobject_uevent(&ioa_cfg->host->shost_dev.kobj, KOBJ_CHANGE); LEAVE; } @@ -9908,6 +9923,7 @@ static void ipr_init_ioa_cfg(struct ipr_ INIT_LIST_HEAD(&ioa_cfg->free_res_q); INIT_LIST_HEAD(&ioa_cfg->used_res_q); INIT_WORK(&ioa_cfg->work_q, ipr_worker_thread); + INIT_WORK(&ioa_cfg->scsi_add_work_q, ipr_add_remove_thread); init_waitqueue_head(&ioa_cfg->reset_wait_q); init_waitqueue_head(&ioa_cfg->msi_wait_q); init_waitqueue_head(&ioa_cfg->eeh_wait_q); --- a/drivers/scsi/ipr.h +++ b/drivers/scsi/ipr.h @@ -1568,6 +1568,7 @@ struct ipr_ioa_cfg { u8 saved_mode_page_len; struct work_struct work_q; + struct work_struct scsi_add_work_q; struct workqueue_struct *reset_work_q; wait_queue_head_t reset_wait_q;