Re: v2.6.26-rc9: kernel BUG at kernel/sched.c:5858!

["Vegard Nossum" <vegard.nossum@gmail.com>]

On Thu, Jul 10, 2008 at 1:59 PM, Vegard Nossum <vegard.nossum@gmail.com> wrote:
> Hi,
>
> Looks like CPU hotplug still has some problems. Just got this on
> latest mainline, and I couldn't find the exact same report on LKML
> or kerneloops, maybe it can be helpful for debugging the existing
> problem(s)?
>
> lockdep: fixing up alternatives.
> ------------[ cut here ]------------
> kernel BUG at kernel/sched.c:5858!
> invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
> Pid: 3934, comm: bash Not tainted (2.6.26-rc9-00057-g60d678c #3)
> EIP: 0060:[<c057f7c5>] EFLAGS: 00210046 CPU: 0
> EIP is at migration_call+0x495/0x4d0
> EAX: 00000000 EBX: c0803f00 ECX: f6bd0000 EDX: 017b0000
> ESI: e7d24fb0 EDI: c1fb3f00 EBP: f62e7e78 ESP: f62e7e48
>  DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
> Process bash (pid: 3934, ti=f62e6000 task=f60fbfc0 task.ti=f62e6000)
> Stack: 00000000 c06ddf70 f62e7e6c 00200246 c0803f00 00000001 c1fb3f00 f62e7e6c
>       c0581fcf c074ec70 ffffffff 00000000 f62e7e98 c014d5a7 00000001 00000007
>       c074ecf4 ffffffff 00000001 e7c86f90 f62e7eac c014d619 ffffffff 00000000
> Call Trace:
>  [<c0581fcf>] ? preempt_schedule+0x3f/0x50
>  [<c014d5a7>] ? notifier_call_chain+0x37/0x70
>  [<c014d619>] ? __raw_notifier_call_chain+0x19/0x20
>  [<c014d63a>] ? raw_notifier_call_chain+0x1a/0x20
>  [<c055ff68>] ? _cpu_down+0x148/0x240
>  [<c015da8f>] ? cpu_maps_update_begin+0xf/0x20
>  [<c056008b>] ? cpu_down+0x2b/0x40
>  [<c05612a9>] ? store_online+0x39/0x80
>  [<c0561270>] ? store_online+0x0/0x80
>  [<c02fba7b>] ? sysdev_store+0x2b/0x40
>  [<c01dd0f2>] ? sysfs_write_file+0xa2/0x100
>  [<c019ed76>] ? vfs_write+0x96/0x130
>  [<c01dd050>] ? sysfs_write_file+0x0/0x100
>  [<c019f43d>] ? sys_write+0x3d/0x70
>  [<c0104ceb>] ? sysenter_past_esp+0x78/0xd1
>  =======================
> Code: 45 e8 e8 2f 53 00 00 b8 01 00 00 00 e9 a2 fb ff ff bb 60 36 59 c0 eb 02 8b
>  1b 89 f8 ff 53 18 85 c0 89 c6 74 f3 90 e9 89 fe ff ff <0f> 0b eb fe 8d b4 26 00
>  00 00 00 e8 8b 82 bd ff 89 f0 50 9d 0f
> EIP: [<c057f7c5>] migration_call+0x495/0x4d0 SS:ESP 0068:f62e7e48
>
>
> Oh, I just saw
>
> commit dc7fab8b3bb388c57c6c4a43ba68c8a32ca25204
> Author: Dmitry Adamushko <dmitry.adamushko@gmail.com>
> Date:   Thu Jul 10 00:32:40 2008 +0200
>
>   sched: fix cpu hotplug
>
> will apply and retry. Is this likely to fix the oops I saw, though?

Nope, I get the same thing (just 2 lines offset):

------------[ cut here ]------------
kernel BUG at kernel/sched.c:5860!
invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Pid: 3879, comm: bash Not tainted (2.6.26-rc9-00058-g2515e04 #4)
EIP: 0060:[<c057f7d5>] EFLAGS: 00210046 CPU: 0
EIP is at migration_call+0x495/0x4d0
EAX: 00000000 EBX: c0593600 ECX: c1f65e80 EDX: 017b0000
ESI: f6d08000 EDI: c1fb3f00 EBP: ccdf3e78 ESP: ccdf3e48
 DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
Process bash (pid: 3879, ti=ccdf2000 task=e7bb6f90 task.ti=ccdf2000)
Stack: 00000000 c06ddf70 ccdf3e6c 00200246 c0803f00 00000001 c1fb3f00 ccdf3e6c
       c0581fdf c074ec70 ffffffff 00000000 ccdf3e98 c014d5b7 00000001 00000007
       c074ecf4 ffffffff 00000001 e7beafd0 ccdf3eac c014d629 ffffffff 00000000
Call Trace:
 [<c0581fdf>] ? preempt_schedule+0x3f/0x50
 [<c014d5b7>] ? notifier_call_chain+0x37/0x70
 [<c014d629>] ? __raw_notifier_call_chain+0x19/0x20
 [<c014d64a>] ? raw_notifier_call_chain+0x1a/0x20
 [<c055ff78>] ? _cpu_down+0x148/0x240
 [<c015da9f>] ? cpu_maps_update_begin+0xf/0x20
 [<c056009b>] ? cpu_down+0x2b/0x40
 [<c05612b9>] ? store_online+0x39/0x80
 [<c0561280>] ? store_online+0x0/0x80
 [<c02fba8b>] ? sysdev_store+0x2b/0x40
 [<c01dd102>] ? sysfs_write_file+0xa2/0x100
 [<c019ed86>] ? vfs_write+0x96/0x130
 [<c01dd060>] ? sysfs_write_file+0x0/0x100
 [<c019f44d>] ? sys_write+0x3d/0x70
 [<c0104ceb>] ? sysenter_past_esp+0x78/0xd1
 =======================
Code: 45 e8 e8 2f 53 00 00 b8 01 00 00 00 e9 a2 fb ff ff bb 60 36 59
c0 eb 02 8b 1b 89 f8 ff 53 18 85 c0 89 c6 74 f3 90 e9 89 fe ff ff <0f>
0b eb fe 8d b4 26 00 00 00 00 e8 8b 82 bd ff 89 f0 50 9d 0f


Vegard

-- 
"The animistic metaphor of the bug that maliciously sneaked in while
the programmer was not looking is intellectually dishonest as it
disguises that the error is the programmer's own creation."
	-- E. W. Dijkstra, EWD1036