From nobody Wed Sep 3 02:01:01 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2C19BC6FA82 for ; Fri, 2 Sep 2022 12:33:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236825AbiIBMdV (ORCPT ); Fri, 2 Sep 2022 08:33:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36696 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236702AbiIBMcF (ORCPT ); Fri, 2 Sep 2022 08:32:05 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E75E8E1934; Fri, 2 Sep 2022 05:27:23 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 2A10EB82AA2; Fri, 2 Sep 2022 12:25:26 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 868D0C433D7; Fri, 2 Sep 2022 12:25:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1662121524; bh=datHgiSjND2VmkLLoF7eduR5OnhuevfGSmxmRwUU9Jg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sCUSvf4kzN5e+Tj84nq2/X2zb5mdjSEoHAlZcrh2D/vTkLiZakf3mzwzvxECs2AHp nJv2ODDrhDT5DBV9yOo3bNETSOa3vxq3SbAiKTIHvCQVJsKGeojTplKnd77jikU/Wa KM27q+3hw2DEYuJS3OnhWNLvmRt6Urz0URCS++dE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Michael Kelley , Saurabh Sengar , "Martin K. Petersen" Subject: [PATCH 4.19 36/56] scsi: storvsc: Remove WQ_MEM_RECLAIM from storvsc_error_wq Date: Fri, 2 Sep 2022 14:18:56 +0200 Message-Id: <20220902121401.554898954@linuxfoundation.org> X-Mailer: git-send-email 2.37.3 In-Reply-To: <20220902121400.219861128@linuxfoundation.org> References: <20220902121400.219861128@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Saurabh Sengar commit d957e7ffb2c72410bcc1a514153a46719255a5da upstream. storvsc_error_wq workqueue should not be marked as WQ_MEM_RECLAIM as it doesn't need to make forward progress under memory pressure. Marking this workqueue as WQ_MEM_RECLAIM may cause deadlock while flushing a non-WQ_MEM_RECLAIM workqueue. In the current state it causes the following warning: [ 14.506347] ------------[ cut here ]------------ [ 14.506354] workqueue: WQ_MEM_RECLAIM storvsc_error_wq_0:storvsc_remove_= lun is flushing !WQ_MEM_RECLAIM events_freezable_power_:disk_events_workfn [ 14.506360] WARNING: CPU: 0 PID: 8 at <-snip->kernel/workqueue.c:2623 ch= eck_flush_dependency+0xb5/0x130 [ 14.506390] CPU: 0 PID: 8 Comm: kworker/u4:0 Not tainted 5.4.0-1086-azur= e #91~18.04.1-Ubuntu [ 14.506391] Hardware name: Microsoft Corporation Virtual Machine/Virtual= Machine, BIOS Hyper-V UEFI Release v4.1 05/09/2022 [ 14.506393] Workqueue: storvsc_error_wq_0 storvsc_remove_lun [ 14.506395] RIP: 0010:check_flush_dependency+0xb5/0x130 <-snip-> [ 14.506408] Call Trace: [ 14.506412] __flush_work+0xf1/0x1c0 [ 14.506414] __cancel_work_timer+0x12f/0x1b0 [ 14.506417] ? kernfs_put+0xf0/0x190 [ 14.506418] cancel_delayed_work_sync+0x13/0x20 [ 14.506420] disk_block_events+0x78/0x80 [ 14.506421] del_gendisk+0x3d/0x2f0 [ 14.506423] sr_remove+0x28/0x70 [ 14.506427] device_release_driver_internal+0xef/0x1c0 [ 14.506428] device_release_driver+0x12/0x20 [ 14.506429] bus_remove_device+0xe1/0x150 [ 14.506431] device_del+0x167/0x380 [ 14.506432] __scsi_remove_device+0x11d/0x150 [ 14.506433] scsi_remove_device+0x26/0x40 [ 14.506434] storvsc_remove_lun+0x40/0x60 [ 14.506436] process_one_work+0x209/0x400 [ 14.506437] worker_thread+0x34/0x400 [ 14.506439] kthread+0x121/0x140 [ 14.506440] ? process_one_work+0x400/0x400 [ 14.506441] ? kthread_park+0x90/0x90 [ 14.506443] ret_from_fork+0x35/0x40 [ 14.506445] ---[ end trace 2d9633159fdc6ee7 ]--- Link: https://lore.kernel.org/r/1659628534-17539-1-git-send-email-ssengar@l= inux.microsoft.com Fixes: 436ad9413353 ("scsi: storvsc: Allow only one remove lun work item to= be issued per lun") Reviewed-by: Michael Kelley Signed-off-by: Saurabh Sengar Signed-off-by: Martin K. Petersen Signed-off-by: Greg Kroah-Hartman --- drivers/scsi/storvsc_drv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/scsi/storvsc_drv.c +++ b/drivers/scsi/storvsc_drv.c @@ -1858,7 +1858,7 @@ static int storvsc_probe(struct hv_devic */ host_dev->handle_error_wq =3D alloc_ordered_workqueue("storvsc_error_wq_%d", - WQ_MEM_RECLAIM, + 0, host->host_no); if (!host_dev->handle_error_wq) goto err_out2;