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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C3E68C00140 for ; Sun, 21 Aug 2022 21:39:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231800AbiHUVj4 (ORCPT ); Sun, 21 Aug 2022 17:39:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33260 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229541AbiHUVjx (ORCPT ); Sun, 21 Aug 2022 17:39:53 -0400 Received: from mail-pf1-f177.google.com (mail-pf1-f177.google.com [209.85.210.177]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7F63C1E3FD for ; Sun, 21 Aug 2022 14:39:52 -0700 (PDT) Received: by mail-pf1-f177.google.com with SMTP id x15so7775254pfp.4 for ; Sun, 21 Aug 2022 14:39:52 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc; bh=TBTta4D/RBg6tfd42bSdioiS4BURRGR92bmrXX7PSxk=; b=a+AAAAGlxNu0iSrh8ke0N/QwPo3tadXJSGg+6ovsQm86s8uR7Ln6f2FINygfc2rmI1 tjnpaX+Et9HEMiJb3vG2AVL31eFJ+xZPmUxJMjLBBD3OCX9aZpRuLCySR5dEQEUtXW1K bpLenT1NQCjgxBnPOQiRoDtMenL2Lp4UrovEhkz3axujoE+SWn81FCFGfA1+i4eWML3O TkHU7s6PPBohXsJZB+xfFK+68XudtOqtX+N6Oa2IPV0y7tbOtGcljP5ssvnnoXcXCvjO pyKVuQB8zFzglbwoJrL6hBgmIbs9/8BQWLsUADrmJFX1mL0/yLGY7xpoIh9ezETZhjzH iowg== X-Gm-Message-State: ACgBeo2sFD+M5s+1IurG3Y5mbJ2PdXXsUtwTbfNnAhoZ/RgxQycNm+TQ 2iwM1eJFiNpW/HIxTN4U5wgcPtSiLLE= X-Google-Smtp-Source: AA6agR7jBOTXtAvQb55RQQdijz5f57/iDe1kqGfzCOx66Nn9Fu6G2GOy8remsvcztaKAOyV13OWctw== X-Received: by 2002:a63:445a:0:b0:42a:306e:5e30 with SMTP id t26-20020a63445a000000b0042a306e5e30mr12115659pgk.40.1661117991746; Sun, 21 Aug 2022 14:39:51 -0700 (PDT) Received: from [192.168.3.217] ([98.51.102.78]) by smtp.gmail.com with ESMTPSA id q7-20020a170902a3c700b00172bf229dfdsm5189073plb.97.2022.08.21.14.39.49 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 21 Aug 2022 14:39:50 -0700 (PDT) Message-ID: <27d0dde8-344c-1dd0-cc26-0e10c4e1f296@acm.org> Date: Sun, 21 Aug 2022 14:39:48 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.1.2 Subject: Re: [PATCH v2] driver core: Fix bus_type.match() error handling Content-Language: en-US To: Guenter Roeck Cc: Isaac Manjarres , Greg Kroah-Hartman , "Rafael J. Wysocki" , Ulf Hansson , Tomeu Vizoso , Russell King , Marek Szyprowski , Saravana Kannan , stable@kernel.org, kernel-team@android.com, linux-kernel@vger.kernel.org References: <20220817010559.GA1880847@roeck-us.net> <20220818225932.GA3433999@roeck-us.net> <20220819112832.GA3106213@roeck-us.net> <20220819220841.GA3230067@roeck-us.net> <12b231ea-dc7d-bb09-3986-32a07a63acd4@acm.org> <20220820114801.GA3958319@roeck-us.net> From: Bart Van Assche In-Reply-To: <20220820114801.GA3958319@roeck-us.net> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 8/20/22 04:48, Guenter Roeck wrote: > INFO: task init:283 blocked for more than 122 seconds. > Tainted: G N 6.0.0-rc1-00303-g963a70bee588 #3 > "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > task:init state:D stack: 0 pid: 283 ppid: 1 flags:0x00000000 > __schedule from schedule+0x70/0x118 > schedule from scsi_remove_host+0x178/0x1c4 > scsi_remove_host from usb_stor_disconnect+0x40/0xe8 > usb_stor_disconnect from usb_unbind_interface+0x78/0x274 > usb_unbind_interface from device_release_driver_internal+0x1a4/0x230 > device_release_driver_internal from bus_remove_device+0xd0/0x100 > bus_remove_device from device_del+0x174/0x3ec > device_del from usb_disable_device+0xcc/0x178 > usb_disable_device from usb_disconnect+0xcc/0x274 > usb_disconnect from usb_disconnect+0x98/0x274 > usb_disconnect from usb_remove_hcd+0xd0/0x16c > usb_remove_hcd from host_stop+0x38/0xa8 > host_stop from ci_hdrc_remove+0x40/0x134 > ci_hdrc_remove from platform_remove+0x24/0x54 > platform_remove from device_release_driver_internal+0x1a4/0x230 > device_release_driver_internal from bus_remove_device+0xd0/0x100 > bus_remove_device from device_del+0x174/0x3ec > device_del from platform_device_del.part.0+0x10/0x78 > platform_device_del.part.0 from platform_device_unregister+0x18/0x28 > platform_device_unregister from ci_hdrc_remove_device+0xc/0x24 > ci_hdrc_remove_device from ci_hdrc_imx_remove+0x28/0xfc > ci_hdrc_imx_remove from device_shutdown+0x178/0x230 > device_shutdown from __do_sys_reboot+0x168/0x258 > __do_sys_reboot from ret_fast_syscall+0x0/0x1c Hi Guenter, Thank you for having shared this information. I think this deadlock is the result of holding a reference on /dev/sda (by the mount() system call) while calling scsi_remove_host(). It seems wrong to me that ci_hdrc_imx_shutdown() calls ci_hdrc_imx_remove() - I think that function should only do the minimum that is required to prepare for shutdown instead of calling scsi_remove_host() indirectly. That being said, the patch series "scsi: core: Call blk_mq_free_tag_set() earlier" probably will have to be reverted because of the following deadlock reported by syzbot: https://lore.kernel.org/linux-scsi/000000000000b5187d05e6c08086@google.com/ Thanks, Bart.