Re: [Xen-devel] What is the current state of Dom0 kernel support? / crash

[Jeremy Fitzhardinge <jeremy@xxxxxxxx>]

On 07/22/09 12:35, Pasi Kärkkäinen wrote:
> On Wed, Jul 22, 2009 at 12:14:37PM -0700, Jeremy Fitzhardinge wrote:
>   
>> On 07/21/09 06:03, Pasi Kärkkäinen wrote:
>>     
>>> I just tried the latest 32b PAE rebase/master tree (2.6.31-rc3).
>>>
>>> http://pasik.reaktio.net/xen/pv_ops-dom0-debug/pv_ops-dom0-log-10-rebase-master-with-highpte.txt
>>>
>>> Checking if this processor honours the WP bit even in supervisor mode...
>>> BUG: unable to handle kernel NULL pointer dereference at (null)
>>> IP: [<c058cdcb>] xen_evtchn_do_upcall+0xcc/0x13f
>>> *pdpt = 000000003d275001 
>>> Thread overran stack, or stack corrupted
>>> Oops: 0000 [#1] SMP 
>>> last sysfs file: 
>>> Modules linked in:
>>>
>>> Pid: 0, comm: swapper Not tainted (2.6.31-rc3 #20) P8SC8
>>> EIP: 0061:[<c058cdcb>] EFLAGS: 00010046 CPU: 0
>>> EIP is at xen_evtchn_do_upcall+0xcc/0x13f
>>> EAX: 00000000 EBX: ffffffff ECX: 00000000 EDX: 00000000
>>> ESI: 00000000 EDI: c08ec558 EBP: c087eedc ESP: c087eea0
>>>  DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: e021
>>> Process swapper (pid: 0, ti=c087e000 task=c083b1a0 task.ti=c087e000)
>>> Stack:
>>>  00001a6e 00000220 00000200 00000000 00000000 00000000 e3201014 c08ec558
>>> <0> c087eee4 f5681000 e3201010 00000000 00000000 c09017f8 f54ff000 c087ef20
>>> <0> c0409927 00000000 c09017f8 f54ff000 c09017f8 f54ff000 c087ef20 c0843f70
>>> Call Trace:
>>>  [<c0409927>] ? xen_do_upcall+0x7/0xc
>>>  [<c0404581>] ? xen_pte_clear+0x9/0x12
>>>  [<c0427a94>] ? set_pte_vaddr+0xb4/0xc4
>>>  [<c0426c8c>] ? __native_set_fixmap+0x25/0x30
>>>  [<c040471a>] ? xen_set_fixmap+0xc7/0xcc
>>>  [<c0897d86>] ? mem_init+0x24a/0x298
>>>  [<c088367e>] ? start_kernel+0x14b/0x2cd
>>>  [<c088336f>] ? unknown_bootoption+0x0/0x18e
>>>  [<c0883082>] ? i386_start_kernel+0x71/0x79
>>>  [<c0886188>] ? xen_start_kernel+0x52a/0x533
>>> Code: d0 89 45 cc 89 55 c8 eb 16 0f bc c8 03 4d d4 8b 04 8a 83 f8 ff 74 f8
>>> 8b 55 e4 e8 36 de e7 ff 8b 55 f0 8b 45 d0 03 
>>> 05 1c 0c 97 c0 <8b> 0c 10 8b 55 e8 8b 45 cc 23 0c 82 8b 45 c8 8b 04 82 8b 15
>>> 18 
>>> EIP: [<c058cdcb>] xen_evtchn_do_upcall+0xcc/0x13f SS:ESP e021:c087eea0
>>> CR2: 0000000000000000
>>> ---[ end trace 4eaa2a86a8e2da22 ]---
>>> Kernel panic - not syncing: Fatal exception in interrupt
>>>   
>>>       
>> Haven't seen that one before.  
>>
>>     
>
> Ok. I've seen many people report crashes during startup with rebase/master
> on 32b PAE. I assume they're seeing this same issue.
>   

Unfortunately its a bit awkward for me to test 32-bit regularly, so I
rely on other reports.  IanC did send me a success report from the -rc1
kernel, but its quite likely something changed since then.  It shouldn't
be too hard to work out once we can pinpoint the crash site.

>> The stack backtrace is a bit fuzzy; do you have CONFIG_FRAMEPOINTER enabled? 
>>  
>> And if you have CONFIG_DEBUGINFO enabled, you can map the eip c058cdcb 
>> to a specific source line (its not clear to me which pointer is NULL).
>>
>>     
>
> [root@dom0test linux-2.6-xen]# grep -i CONFIG_FRAMEPOINTER .config
> [root@dom0test linux-2.6-xen]# grep -i CONFIG_DEBUGINFO .config
> [root@dom0test linux-2.6-xen]# 
>
> Unfortunately those were not enabled.. I'll build a new kernel with
> CONFIG_DEBUGINFO enabled.
>   

Thanks,
    J


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