From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751763AbbKJImo (ORCPT ); Tue, 10 Nov 2015 03:42:44 -0500 Received: from mail.ab3.no ([176.58.113.160]:42724 "EHLO mail.ab3.no" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750899AbbKJImm convert rfc822-to-8bit (ORCPT ); Tue, 10 Nov 2015 03:42:42 -0500 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Date: Tue, 10 Nov 2015 09:42:36 +0100 From: =?UTF-8?Q?Mads_L=C3=B8nsethagen?= To: =?UTF-8?Q?Mads_L=C3=B8nsethagen?= Cc: linux-kernel@vger.kernel.org Subject: Re: BUG: unable to handle kernel NULL pointer dereference when mounting/umounting vfat in 4.3.0, worked in 4.2.4 In-Reply-To: <3807a278a4e56c0b478d460e794e6484@ab3.no> References: <3807a278a4e56c0b478d460e794e6484@ab3.no> Message-ID: Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2015-11-06 21:37, Mads Lønsethagen wrote: > After updating from 4.2.4 to 4.3.0 I cannot seem to list files in my > /boot-folder after mounting it, and I get a kernel BUG when I try to > umount it. > > exai ~ # mount /⁠boot > exai ~ # sync > exai ~ # mount > [ ... snip ... ] > /dev/sda1 on /boot type vfat > (rw,noatime,fmask=0022,dmask=0022,codepage=865,iocharset=utf8,shortname=mixed,errors=remount-ro) > tmpfs on /run/user/1000 type tmpfs > (rw,nosuid,nodev,relatime,size=808900k,mode=700,uid=1000,gid=1000) > exai ~ # ls -⁠l /⁠boot > ls: cannot open directory /⁠boot: No such device or address > exai ~ # umount /⁠boot/⁠ > Killed > exai ~ # dmesg | tail -⁠50 > [ 47.959725] cfg80211: (5150000 KHz - 5250000 KHz @ 80000 KHz, 200000 > KHz AUTO), (N/A, 2000 mBm), (N/A) > [ 47.959726] cfg80211: (5250000 KHz - 5350000 KHz @ 80000 KHz, 200000 > KHz AUTO), (N/A, 2000 mBm), (0 s) > [ 47.959727] cfg80211: (5470000 KHz - 5725000 KHz @ 160000 KHz), (N/A, > 2698 mBm), (0 s) > [ 47.959728] cfg80211: (57000000 KHz - 66000000 KHz @ 2160000 KHz), > (N/A, 4000 mBm), (N/A) > [ 101.965931] BUG: unable to handle kernel NULL pointer dereference at > 0000000000000028 > [ 101.966053] IP: [] > truncate_inode_pages_range+0x1e/0x6a0 > [ 101.966152] PGD 838e7067 PUD 6c8db067 PMD 0 > [ 101.966222] Oops: 0000 [#1] PREEMPT SMP > [ 101.966300] Modules linked in: iwlmvm iwlwifi vfat fat uvcvideo > videobuf2_vmalloc videobuf2_memops videobuf2_core v4l2_common videodev > x86_pkg_temp_thermal coretemp kvm_intel kvm microcode i2c_i801 iTCO_wdt > xhci_pci xhci_hcd ideapad_laptop sparse_keymap int3403_thermal > int3402_thermal processor_thermal_device int340x_thermal_zone > intel_soc_dts_iosf int3400_thermal iosf_mbi acpi_thermal_rel > intel_smartconnect efivarfs > [ 101.967059] CPU: 0 PID: 1311 Comm: umount Not tainted 4.3.0-⁠gentoo > #1 > [ 101.967151] Hardware name: LENOVO 20266/Yoga2, BIOS 76CN42WW > 03/02/2015 > [ 101.967206] task: ffff880087a23000 ti: ffff88006c92c000 task.ti: > ffff88006c92c000 > [ 101.967269] RIP: 0010:[] [] > truncate_inode_pages_range+0x1e/0x6a0 > [ 101.967354] RSP: 0018:ffff88006c92fcd0 EFLAGS: 00010282 > [ 101.967395] RAX: 0000000000000000 RBX: ffffffffffffffff RCX: > 9e37fffffffc0001 > [ 101.967453] RDX: ffffffffffffffff RSI: 0000000000000000 RDI: > ffff88008897c770 > [ 101.967512] RBP: 0000000000000000 R08: 0000000000000000 R09: > 0000000000000000 > [ 101.967571] R10: ffff88008897c718 R11: 0000000000000000 R12: > ffffffffa03468c0 > [ 101.967630] R13: ffff88006c930000 R14: ffff8802532bd438 R15: > ffff88008897c690 > [ 101.967689] FS: 00007fabc7f61780(0000) GS:ffff88025f200000(0000) > knlGS:0000000000000000 > [ 101.967757] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ 101.967802] CR2: 0000000000000028 CR3: 000000006c8df000 CR4: > 00000000001406f0 > [ 101.967880] Stack: > [ 101.967897] ffff88008897c770 0000000000000000 ffff880087a23000 > 0000000000000000 > [ 101.967966] ffffffff81100678 0000000000000000 ffffffff810fefd6 > ffff88006c92fe58 > [ 101.968034] 00ffffff00000000 00000002900e19c0 ffffffff810fd640 > ffff8802540b8248 > [ 101.968102] Call Trace: > [ 101.968117] [] ? pagevec_lookup_tag+0x18/⁠0x20 > [ 101.968167] [] ? write_cache_pages+0xe6/⁠0x390 > [ 101.968215] [] ? domain_dirty_limits+0xe0/⁠0xe0 > [ 101.968266] [] ? finish_task_switch+0x53/⁠0x180 > [ 101.968316] [] ? find_get_pages_tag+0x126/⁠0x160 > [ 101.968366] [] ? > __inode_wait_for_writeback+0x62/0xb0 > [ 101.968422] [] ? autoremove_wake_function+0x30/0x30 > [ 101.968478] [] ? fat_evict_inode+0x10/⁠0x50 [fat] > [ 101.968530] [] ? evict+0xb3/⁠0x180 > [ 101.968567] [] ? dispose_list+0x2d/⁠0x40 > [ 101.968611] [] ? evict_inodes+0x13a/⁠0x150 > [ 101.968656] [] ? generic_shutdown_super+0x35/⁠0xe0 > [ 101.968707] [] ? kill_block_super+0x1c/⁠0x60 > [ 101.968754] [] ? deactivate_locked_super+0x34/⁠0x60 > [ 101.968806] [] ? cleanup_mnt+0x36/⁠0x80 > [ 101.968860] [] ? task_work_run+0x6f/⁠0x90 > [ 101.968917] [] ? prepare_exit_to_usermode+0x95/0xd0 > [ 101.968971] [] ? int_ret_from_sys_call+0x25/⁠0x8f > [ 101.969021] Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 41 57 41 56 > 41 55 41 54 55 48 89 f5 53 48 89 d3 48 81 ec 10 01 00 00 48 8b 07 48 89 > 3c 24 <48> 8b 40 28 8b 80 08 04 00 00 85 c0 78 05 e8 cf 19 04 00 48 8b > [ 101.969295] RIP [] > truncate_inode_pages_range+0x1e/0x6a0 > [ 101.969355] RSP > [ 101.969377] CR2: 0000000000000028 > [ 101.990401] -⁠-⁠-⁠[ end trace a5cb453620b7ad23 ]-⁠-⁠-⁠ > exai ~ # > Fortunately, I'm not able to reproduce this. I think the problem stemmed from doing a small change in menuconfig and then forgetting to copy out the new bzImage to /boot but having the new modules installed. Sorry for the noise. - Mads