[systemd-devel] Kernel BUG() on shutdown

[Andrew Edmunds]

Hi,

I got a kernel BUG() today as my machine was shutting down under systemd.  See output below.

A quick browse on LKML suggests that this is related to the scheduling of cpu-groups. It
looks like the relevant code has had some changes recently so there is at least the
possibility that the issue is already fixed in the latest kernel.  See:
http://lkml.org/lkml/2010/10/20/339

At the moment I not sure whether something in the shutdown specifically triggered it or
whether the timing was just coincidental.

Has anyone else seen this?


# systemctl reboot
Stopping /sys/fs/fuse/connections...
Stopping LSB: Set the CPU Frequency Scaling governor to "ondemand"...
Stopping LSB: Run /etcrc.local if it exist...
Stopping acpi-support.service...
Stopping LSB: Record successful boot for GRUB...
Stopping Getty on tty5...
Stopping Getty on tty3...
Stopping Getty on tty2...
Stopping Getty on tty6...
Stopping Getty on tty1...
Stopping Getty on tty4...
Stopping Serial Getty on ttyS0...
Starting Save Random Seed...
Stopping Permit User Sessions...
 * Disabling power management...
   ...done.
Stopping LSB: Speech Dispatcher...
Stopping LSB: SANE network scanner server...
Stopping LSB: Restore resolv.conf if the system crashed....
Stopping LSB: Start NTP daemon...
Stopping LSB: Tool to automatically collect and submit kernel crash signatures...
Stopping LSB: start and stop the Postfix Mail Transport Agent...
Stopping LSB: Cleans up any mess left by 0dns-up...
Stopping LSB: VirtualBox Additions service...
Stopping LSB: Start the PulseAudio sound server...
Stopping LSB: Start bluetoothd...
Stopping sudo.service...
Stopping LSB: fancontrol...
Stopping LSB: Load crashkernel image with kexec...
Stopping LSB: fast remote file copy program daemon...
Stopping LSB: Support for extra binary formats...
saned disabled; edit /etc/default/saned
speech-dispatcher disabled; edit /etc/default/speech-dispatcher
Stopping VirtualBox Guest Addition service  * PulseAudio configured for per-user sessions
 * Stopping rsync daemon rsync
 * Stopping fan speed regulator fancontrol
Stopping D-Bus System Message Bus...
   ...done.
   ...done.
 * Disabling additional executable inary formats binfmt-support
 * Stopping NTP server ntpd
 ...done.
Stopping LSB: VirtualBox Linux Additions kernel modules...
Starting systemd Syslog Kernel Log Buffer Bridge...
   ...done.
 * Stopping Postfix Mail Transport Agent postfix
   ...done.
Stopping VirtualBox Additions ...done.
   ...done.
Stopping Apply Kernel Variables...
Stopping Apply System Clock UTC Offset...
Starting Update RTC With System Clock..
Starting Notify Audit System and Update UTMP about System Shutdown...
Stopping Lock Directory...
Stopping Runtime Directory...
Stopping Remount Root FS...
Stopping Remount API VFS...
[   79.173073] BUG: unable to handle kernel NULL pointer dereference at 0000001c
[   79.175071] IP: [<c01443b4>] set_next_entity+0x14/0xe0
[   79.176046] *pde = 2d918067 *pte = 00000000
[   79.176046] Oops: 0000 [#1] SMP
[   79.176046] last sysfs file: /sys/module/pcie_aspm/parameters/policy
[   79.176046] Modules linked in: snd_intel8x0 snd_ac97_codec ac97_bus snd_pcm binfmt_misc snd_seq_midi snd_rawmidi snd_seq_midi_event snd_seq snd_timer snd_seq_device snd soundcore snd_page_alloc ppdev parport_pc i2c_piix4 parport psmouse serio_raw autofs4 floppy pcnet32 mii [last unloaded: vboxguest]
[   79.176046]
[   79.176046] Pid: 1138, comm: systemctl Not tainted 2.6.35-22-generic #35ppa1 /VirtualBox
[   79.176046] EIP: 0060:[<c01443b4>] EFLAGS: 00010082 CPU: 0
[   79.176046] EIP is at set_next_entity+0x14/0xe0
[   79.176046] EAX: ef1ea720 EBX: ef1ea720 ECX: edbed19c EDX: 00000000
[   79.176046] ESI: 00000000 EDI: 00000000 EBP: e3927ee4 ESP: e3927ed0
[   79.176046]  DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
[   79.176046] Process systemctl (pid: 1138, ti=e3926000 task=e396f230 task.ti=e3926000)
[   79.176046] Stack:
[   79.176046]  133e53b7 00000000 ef1ea720 00000000 00000000 e3927efc c014457d c5808700
[   79.176046] <0> 00000000 c5808700 00000000 e3927f54 c05c6bb1 c08c3700 c08c3700 e396f230
[   79.176046] <0> c05d8aa0 c08c3700 c08c3700 00000001 e3927f28 c08c3700 c08c3700 c016abff
[   79.176046] Call Trace:
[   79.176046]  [<c014457d>] ? pick_next_task_fair+0xbd/0x100
[   79.176046]  [<c05c6bb1>] ? schedule+0x4f1/0x7a0
[   79.176046]  [<c016abff>] ? switch_task_namespaces+0x1f/0x60
[   79.176046]  [<c014f079>] ? do_exit+0x1b9/0x340
[   79.176046]  [<c014f23e>] ? do_group_exit+0x3e/0xa0
[   79.176046]  [<c014f2b8>] ? sys_exit_group+0x18/0x20
[   79.176046]  [<c05c9114>] ? syscall_call+0x7/0xb
[   79.176046] Code: e4 83 45 ec 08 8b 45 ec 8b 00 85 c0 89 45 e8 75 d8 e9 77 ff ff ff 90 55 89 e5 83 ec 14 89 5d f4 89 75 f8 89 7d fc 0f 1f 44 00 00 <8b> 4a 1c 89 c6 89 d3 85 c9 0f 85 95 00 00 00 8b 46 40 8b 90 4c
[   79.176046] EIP: [<c01443b4>] set_next_entity+0x14/0xe0 SS:ESP 0068:e3927ed0
[   79.176046] CR2: 000000000000001c
[   79.176046] ---[ end trace 19d7c4bdf6f52705 ]---
[   79.176046] Fixing recursive fault but reboot is needed!

-- 
Andrew Edmunds
andrew.edmunds at yahoo.com.au