mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Kees Cook <keescook@chromium.org>
Cc: kernel test robot <xiaolong.ye@intel.com>, LKP <lkp@01.org>,
	LKML <linux-kernel@vger.kernel.org>,
	Rik van Riel <riel@redhat.com>,
	Steven Rostedt <rostedt@goodmis.org>
Subject: Re: [list] 8052ce2d97: WARNING: CPU: 0 PID: 1 at lib/list_debug.c:60 __list_del_entry+0x4d/0x71
Date: Thu, 8 Sep 2016 02:27:12 -0700	[thread overview]
Message-ID: <20160908092712.GI3663@linux.vnet.ibm.com> (raw)
In-Reply-To: <CAGXu5jJFNymPhRp=1Zp829-_wmT2XwzR0Lej2hy_CExQrG1Y5g@mail.gmail.com>

On Wed, Sep 07, 2016 at 10:25:58AM -0700, Kees Cook wrote:
> On Wed, Sep 7, 2016 at 12:31 AM, Paul E. McKenney
> <paulmck@linux.vnet.ibm.com> wrote:
> > On Tue, Sep 06, 2016 at 11:49:04AM -0400, Kees Cook wrote:
> >> On Sun, Sep 4, 2016 at 5:48 AM, Paul E. McKenney
> >> <paulmck@linux.vnet.ibm.com> wrote:
> >> > On Sun, Sep 04, 2016 at 08:35:40AM +0800, kernel test robot wrote:
> >> >>
> >> >> FYI, we noticed the following commit:
> >> >>
> >> >> https://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git dev.2016.08.19a
> >> >> commit 8052ce2d9771ab5a818307f3abbaf33bba82a631 ("list: Split list_add() debug checking into separate function")
> >> >>
> >> >> in testcase: boot
> >> >>
> >> >> on test machine: qemu-system-i386 -enable-kvm -m 360M
> >> >>
> >> >> caused below changes:
> >> >
> >> > Hello, Kees,
> >> >
> >> > Looks like your change might have actually found a bug.  ;-)
> >> >
> >> > How would you like to handle this?
> >>
> >> We should fix the bug! :)
> >
> > But of course...
> >
> > The question is whether I am considered to be fully responsible for
> > chasing down any bugs that arise.  It is looking like I am, in which
> > case I must defer this patch to the 4.10 merge window.  Things are a
> > bit crazy now due to prior overcommitments...
> 
> I'm going to double-check the code, but the changes I made shouldn't
> have changed any of the logical checks under CONFIG_DEBUG_LIST... just
> the manifestation of WARN vs BUG. So, since both this and the BPF RCU
> bug have appeared, something has changed... I will go digging...

So maybe the boot failures are a result of the WARN->BUG transition?

							Thanx, Paul

> -Kees
> 
> > Yes, yes, they will be crazy then as well, but this would be higher
> > on the priority list.
> >
> >                                                         Thanx, Paul
> >
> >> >> +------------------------------------------------------------+------------+------------+
> >> >> |                                                            | 0a33d912a3 | 8052ce2d97 |
> >> >> +------------------------------------------------------------+------------+------------+
> >> >> | boot_successes                                             | 0          | 0          |
> >> >> | boot_failures                                              | 211        | 18         |
> >> >> | WARNING:at_lib/list_debug.c:#__list_del_entry              | 211        | 18         |
> >> >> | calltrace:init                                             | 209        | 18         |
> >> >> | WARNING:at_lib/list_debug.c:#__list_add                    | 209        |            |
> >> >> | calltrace:i8042_init                                       | 209        | 17         |
> >> >> | calltrace:SyS_reboot                                       | 192        | 4          |
> >> >> | EIP_is_at__mutex_unlock_slowpath                           | 29         |            |
> >> >> | Kernel_panic-not_syncing:softlockup:hung_tasks             | 138        |            |
> >> >> | BUG:workqueue_lockup-pool_cpus=#flags=#nice=#stuck_for#s   | 56         |            |
> >> >> | EIP_is_at_lock_release                                     | 7          |            |
> >> >> | EIP_is_at_lock_acquire                                     | 28         |            |
> >> >> | EIP_is_at_raw_spin_unlock_irq                              | 30         |            |
> >> >> | EIP_is_at_mutex_lock_nested                                | 21         |            |
> >> >> | EIP_is_at_lock_is_held                                     | 10         |            |
> >> >> | EIP_is_at_device_shutdown                                  | 3          |            |
> >> >> | EIP_is_at___might_sleep                                    | 5          |            |
> >> >> | EIP_is_at__list_del_entry                                  | 4          | 1          |
> >> >> | EIP_is_at_get_device                                       | 1          |            |
> >> >> | BUG:unable_to_handle_kernel                                | 7          | 5          |
> >> >> | Oops                                                       | 7          | 5          |
> >> >> | calltrace:SyS_ipc                                          | 4          | 4          |
> >> >> | Kernel_panic-not_syncing:Fatal_exception                   | 7          | 5          |
> >> >> | EIP_is_at_pm_runtime_barrier                               | 1          |            |
> >> >> | EIP_is_at_lock_acquired                                    | 1          |            |
> >> >> | EIP_is_at__might_sleep                                     | 1          |            |
> >> >> | BUG:workqueue_lockup-pool_cpus=#-#flags=#nice=#stuck_for#s | 1          |            |
> >> >> | WARNING:at_arch/x86/mm/dump_pagetables.c:#note_page        | 26         |            |
> >> >> | calltrace:mark_rodata_ro                                   | 26         |            |
> >> >> | WARNING:at_lib/list_debug.c:#__list_add_valid              | 0          | 17         |
> >> >> | calltrace:serio_handle_event                               | 0          | 17         |
> >> >> | calltrace:userio_misc_init                                 | 0          | 17         |
> >> >> | calltrace:mousedev_init                                    | 0          | 17         |
> >> >> | calltrace:evdev_init                                       | 0          | 17         |
> >> >> | calltrace:cmos_init                                        | 0          | 17         |
> >> >> | calltrace:test_init                                        | 0          | 17         |
> >> >> | calltrace:pca_isa_driver_init                              | 0          | 17         |
> >> >> | calltrace:vim2m_init                                       | 0          | 17         |
> >> >> | calltrace:fm_drv_init                                      | 0          | 17         |
> >> >> | calltrace:test_power_init                                  | 0          | 17         |
> >> >> | calltrace:raid#_init                                       | 0          | 17         |
> >> >> | calltrace:dm_init                                          | 0          | 17         |
> >> >> | calltrace:vhci_init                                        | 0          | 17         |
> >> >> | calltrace:dcdrbu_init                                      | 0          | 17         |
> >> >> | calltrace:dcdbas_init                                      | 0          | 17         |
> >> >> | calltrace:uhid_init                                        | 0          | 17         |
> >> >> | calltrace:vhost_net_init                                   | 0          | 17         |
> >> >> | calltrace:dummy_stm_init                                   | 0          | 17         |
> >> >> | calltrace:stm_heartbeat_init                               | 0          | 17         |
> >> >> | calltrace:binder_init                                      | 0          | 17         |
> >> >> | calltrace:teql_init                                        | 0          | 17         |
> >> >> | calltrace:ipip_init                                        | 0          | 17         |
> >> >> | calltrace:ipgre_init                                       | 0          | 17         |
> >> >> | calltrace:sit_init                                         | 0          | 17         |
> >> >> | calltrace:ip6_tunnel_init                                  | 0          | 17         |
> >> >> | calltrace:ip6gre_init                                      | 0          | 17         |
> >> >> | calltrace:irlan_init                                       | 0          | 17         |
> >> >> | calltrace:pm_qos_power_init                                | 0          | 17         |
> >> >> | calltrace:ubi_init                                         | 0          | 17         |
> >> >> | calltrace:SyS_setsockopt                                   | 0          | 2          |
> >> >> | calltrace:SyS_socketcall                                   | 0          | 2          |
> >> >> | WARNING:at_include/linux/kref.h:#kobject_get               | 0          | 4          |
> >> >> | WARNING:at_kernel/locking/lockdep.c:#__lock_acquire        | 0          | 4          |
> >> >> | BUG:kernel_hang_in_test_stage                              | 0          | 4          |
> >> >> | calltrace:fw_cfg_sysfs_init                                | 0          | 7          |
> >> >> +------------------------------------------------------------+------------+------------+
> >> >>
> >> >>
> >> >>
> >> >> [  152.680291] g_acm_ms usbip-vudc.0: failed to start g_acm_ms: -22
> >> >> [  152.689209] usbip-vudc: probe of usbip-vudc.0 failed with error -22
> >> >> [  152.698509] ------------[ cut here ]------------
> >> >> [  152.709786] WARNING: CPU: 0 PID: 1 at lib/list_debug.c:60 __list_del_entry+0x4d/0x71
> >> >> [  152.722785] list_del corruption. next->prev should be cc0230d4, but was 6b6b6b6b
> >>
> >> That's the poison value, so this is a remove-after-remove bug?
> >>
> >> >> [  152.732828] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.8.0-rc1-00033-g8052ce2 #1
> >> >> [  152.742576] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Debian-1.8.2-1 04/01/2014
> >> >> [  152.754081]  00000000 00200246 c0033e78 c13c456b c0033ea4 c13e72ac c0033e90 c103fd02
> >> >> [  152.765720]  0000003c 6b6b6b6b cc0230d4 cc02300c c0033eac c103fd41 00000009 00000000
> >> >> [  152.776864]  c0033ea4 c1f7bc14 c0033ec0 c0033ecc c13e72ac c1f7bace 0000003c c1f7bc14
> >> >> [  152.788472] Call Trace:
> >> >> [  152.791964]  [<c13c456b>] dump_stack+0x75/0xa9
> >> >> [  152.797835]  [<c13e72ac>] ? __list_del_entry+0x4d/0x71
> >> >> [  152.804221]  [<c103fd02>] __warn+0xad/0xc4
> >> >> [  152.809694]  [<c103fd41>] warn_slowpath_fmt+0x28/0x2d
> >> >> [  152.816501]  [<c13e72ac>] __list_del_entry+0x4d/0x71
> >> >> [  152.822946]  [<c15027a8>] device_pm_remove+0x2b/0x5a
> >> >> [  152.829560]  [<c14f6317>] device_del+0x134/0x19a
> >> >> [  152.835558]  [<c14f5c38>] ? dev_set_name+0x14/0x16
> >> >> [  152.842135]  [<c14f9d7c>] platform_device_del+0x16/0x5d
> >> >> [  152.848909]  [<c2207515>] init+0xe5/0x112
> >> >> [  152.854149]  [<c2207430>] ? usbip_host_init+0xe5/0xe5
> >>
> >> What device is this? Looks like it's being removed right at init time??
> >>
> >> >> [  152.860796]  [<c21cec35>] do_one_initcall+0x7e/0x101
> >> >> [  152.867316]  [<c10564b7>] ? parse_args+0x190/0x265
> >> >> [  152.873497]  [<c21ced88>] ? kernel_init_freeable+0xd0/0x174
> >> >> [  152.880923]  [<c21ceda4>] kernel_init_freeable+0xec/0x174
> >> >> [  152.887499]  [<c1be421b>] kernel_init+0x8/0xd0
> >> >> [  152.893658]  [<c1bec3ae>] ret_from_kernel_thread+0xe/0x30
> >> >> [  152.900759]  [<c1be4213>] ? rest_init+0x111/0x111
> >> >> [  152.907334] ---[ end trace 2003739b08d25430 ]---
> >> >> [  152.920040] ------------[ cut here ]------------
> >>
> >> -Kees
> >>
> >>
> >> --
> >> Kees Cook
> >> Nexus Security
> >>
> >
> 
> 
> 
> -- 
> Kees Cook
> Nexus Security
> 

  reply	other threads:[~2016-09-08  9:27 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <57cb6c5c.ht1t4TgNR/5nHu0Z%xiaolong.ye@intel.com>
2016-09-04  9:48 ` Paul E. McKenney
2016-09-06 15:49   ` Kees Cook
2016-09-07  7:31     ` Paul E. McKenney
2016-09-07 17:25       ` Kees Cook
2016-09-08  9:27         ` Paul E. McKenney [this message]
2016-09-08 15:52           ` Kees Cook
2016-10-22  6:08 ` Kees Cook

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20160908092712.GI3663@linux.vnet.ibm.com \
    --to=paulmck@linux.vnet.ibm.com \
    --cc=keescook@chromium.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=lkp@01.org \
    --cc=riel@redhat.com \
    --cc=rostedt@goodmis.org \
    --cc=xiaolong.ye@intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

Powered by JetHome