From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754278AbdJIQFe (ORCPT ); Mon, 9 Oct 2017 12:05:34 -0400 Received: from mail-qk0-f195.google.com ([209.85.220.195]:37348 "EHLO mail-qk0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751834AbdJIQFd (ORCPT ); Mon, 9 Oct 2017 12:05:33 -0400 X-Google-Smtp-Source: AOwi7QAnoRsLvOkLMoXFxMs5FGgnVu/+GrmUPbXRq2qRYJtzA72K+ELfib7B4t8SxB2OV+T4UcBSJw== Date: Mon, 9 Oct 2017 09:05:29 -0700 From: Tejun Heo To: Linus Torvalds Cc: NeilBrown , kernel test robot , Jens Axboe , Christoph Hellwig , Ming Lei , LKML , LKP Subject: Re: [lkp-robot] [blk] 47e0fb461f: BUG:unable_to_handle_kernel Message-ID: <20171009160529.GG3301751@devbig577.frc2.facebook.com> References: <20170921024603.GB8188@yexl-desktop> <87a81or0u2.fsf@notabene.neil.brown.name> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Sat, Sep 30, 2017 at 01:21:13PM -0700, Linus Torvalds wrote: > Tejun, any ideas? The original report is at > > https://lkml.org/lkml/2017/9/20/939 > > in case you don't see it in your inbox from lkml. So, in the full log, there is an earlier warning. [ 60.198729] ------------[ cut here ]------------ [ 60.199708] WARNING: CPU: 0 PID: 1 at drivers/ata/libata-core.c:6533 ata_host_detach+0x65/0xef [ 60.201642] CPU: 0 PID: 1 Comm: swapper Tainted: G S 4.12.0-rc5-00126-g47e0fb46 #1 [ 60.203370] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.3-20161025_171302-gandalf 04/01/2014 [ 60.205276] task: d9b10040 task.stack: d9b0a000 [ 60.206377] EIP: ata_host_detach+0x65/0xef [ 60.207254] EFLAGS: 00210246 CPU: 0 [ 60.208051] EAX: fffffffd EBX: d5f80000 ECX: 00000000 EDX: d57d6a80 [ 60.209158] ESI: 00200282 EDI: 00000000 EBP: d9b0be70 ESP: d9b0be60 [ 60.210262] DS: 007b ES: 007b FS: 0000 GS: 00e0 SS: 0068 [ 60.211264] CR0: 80050033 CR2: 00000000 CR3: 02a75000 CR4: 001406b0 [ 60.212370] Call Trace: [ 60.213060] ata_pci_remove_one+0xe/0x10 [ 60.213914] piix_remove_one+0x25/0x28 [ 60.214750] pci_device_remove+0x1c/0x44 [ 60.215607] driver_probe_device+0x188/0x34d [ 60.216501] __driver_attach+0x64/0xb4 [ 60.217341] bus_for_each_dev+0x4f/0x63 [ 60.218175] driver_attach+0x14/0x16 [ 60.218988] ? driver_probe_device+0x34d/0x34d [ 60.219895] bus_add_driver+0xba/0x1d4 [ 60.220721] driver_register+0x6e/0xa0 [ 60.221562] __pci_register_driver+0x28/0x2b [ 60.222465] ? pdc_sata_pci_driver_init+0x16/0x16 [ 60.223406] piix_init+0x14/0x24 [ 60.224178] do_one_initcall+0x89/0x12d [ 60.225016] ? parse_args+0x102/0x298 [ 60.225915] sd 1:0:0:0: [sda] 16384 512-byte logical blocks: (8.39 MB/8.00 MiB) [ 60.227523] kernel_init_freeable+0xec/0x168 [ 60.228421] ? rest_init+0x6a/0x6a [ 60.229225] kernel_init+0x8/0xcb [ 60.230003] ret_from_fork+0x19/0x30 It looks like somebody is trying to detach the device while async probing is in progress, making later async operations free-after-use. There was a driver core driver detach autotest feature which incorrectly invoked driver detach while async probes are in progress and this looks like that. This has already been fixed. Xialong, can you repro this on the latest kernel? Thanks. -- tejun