Re: [Xen-devel] kernel messages: alignment check: 0000 [#1] SMP

[Teck Choon Giam <giamteckchoon@xxxxxxxxx>]

On Mon, Nov 14, 2011 at 5:59 PM, Jan Beulich <JBeulich@xxxxxxxx> wrote:
>>>> On 13.11.11 at 20:00, Teck Choon Giam <giamteckchoon@xxxxxxxxx> wrote:
>> derefnull[15862]: segfault at 0 ip 000000000804c2eb sp
>> 00000000ffb4dfac error 4 in derefnull[8048000+57000]
>> divbyzero[15899] trap divide error ip:804d0be sp:ff849e9c error:0 in
>> divbyzero[8048000+56000]
>> derefnull[7328]: segfault at 0 ip 0000000000407701 sp 00007fff943b1c60
>> error 4 in derefnull[400000+77000]
>> divbyzero[7345] trap divide error ip:408d05 sp:7fff35784750 error:0 in
>> divbyzero[400000+76000]
>> derefnull[32738]: segfault at 0 ip 000000000804c2eb sp
>> 00000000ffbdbebc error 4 in derefnull[8048000+57000]
>> divbyzero[32755] trap divide error ip:804d0be sp:ffc0f53c error:0 in
>> divbyzero[8048000+56000]
>> derefnull[18732]: segfault at 0 ip 0000000000407701 sp
>> 00007fffec69eb30 error 4 in derefnull[400000+77000]
>> divbyzero[18841] trap divide error ip:408d05 sp:7fffed159ae0 error:0
>> in divbyzero[400000+76000]
>> derefnull[10813]: segfault at 0 ip 000000000804c2eb sp
>> 00000000ffc17dec error 4 in derefnull[8048000+57000]
>> divbyzero[10827] trap divide error ip:804d0be sp:ffdb347c error:0 in
>> divbyzero[8048000+56000]
>> derefnull[27073]: segfault at 0 ip 0000000000407701 sp
>> 00007fff37c6ba00 error 4 in derefnull[400000+77000]
>> divbyzero[27087] trap divide error ip:408d05 sp:7fffc93d8ab0 error:0
>> in divbyzero[400000+76000]
>> derefnull[11819]: segfault at 0 ip 000000000804c2eb sp
>> 00000000ffbb9edc error 4 in derefnull[8048000+57000]
>> divbyzero[11833] trap divide error ip:804d0be sp:ff9c5a1c error:0 in
>> divbyzero[8048000+56000]
>> derefnull[28080]: segfault at 0 ip 0000000000407701 sp
>> 00007fff5d3045d0 error 4 in derefnull[400000+77000]
>> divbyzero[28094] trap divide error ip:408d05 sp:7fff6369ca90 error:0
>> in divbyzero[400000+76000]
>> derefnull[22199]: segfault at 0 ip 000000000804c2eb sp
>> 00000000ffa5f64c error 4 in derefnull[8048000+57000]
>> divbyzero[22213] trap divide error ip:804d0be sp:ffb2c92c error:0 in
>> divbyzero[8048000+56000]
>> derefnull[11755]: segfault at 0 ip 0000000000407701 sp
>> 00007fffe0a4a070 error 4 in derefnull[400000+77000]
>> divbyzero[11768] trap divide error ip:408d05 sp:7fffaac47410 error:0
>> in divbyzero[400000+76000]
>> derefnull[3492]: segfault at 0 ip 000000000804c2eb sp 00000000ff9b0a9c
>> error 4 in derefnull[8048000+57000]
>> divbyzero[3506] trap divide error ip:804d0be sp:ffb387ac error:0 in
>> divbyzero[8048000+56000]
>> derefnull[25591]: segfault at 0 ip 0000000000407701 sp
>> 00007fffc5e82060 error 4 in derefnull[400000+77000]
>> divbyzero[25607] trap divide error ip:408d05 sp:7ffff3882660 error:0
>> in divbyzero[400000+76000]
>
> Up to here (you're certainly aware) are only indications of application 
> faults.

Yes, I know.  Trying to include what is going on in the build system
prior to the kernel message.

>
>> alignment check: 0000 [#1] SMP
>> last sysfs file: /sys/devices/system/cpu/cpu7/cache/index2/shared_cpu_map
>> CPU 7
>> Modules linked in: ipv6 dm_mirror dm_region_hash dm_log microcode
>> rtc_core rtc_lib pcspkr ext3 jbd dm_mod [last unloaded:
>> scsi_wait_scan]
>> Pid: 4002, comm: sbcl Not tainted 2.6.32.47-0.choon.sl6 #1
>> RIP: e030:[<ffffffff810179ff>]  [<ffffffff810179ff>]
>> convert_from_fxsr+0x11f/0x13d
>> RSP: e02b:ffff8800a8301cb8  EFLAGS: 00050246
>
> Something in the kernel has turned on EFLAGS.AC which, in a 64-bit pv
> Xen kernel, must never be done (for it is running itself in ring 3). Tracking
> down where this happens may (unless someone can offer a good guess)
> require sprinkling around respective WARN_ON()s or BUG_ON()s.
>

Ok... thanks for your kind explanation.  I will see whether can I
reproduce this in version 2.6.32.48.  By the way, just the two related
kernel messages and the pv/domU still running as per normal without
any problem though.

Once again, many thanks.

Kindest regards,
Giam Teck Choon

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel