Re: 2.6.29-rc8 pv_ops dom0 BUG / unable to handle kernel paging request

[Jeremy Fitzhardinge <jeremy@goop.org>]

Pasi Kärkkäinen wrote:
> On Sun, Mar 22, 2009 at 12:50:31AM +0200, Pasi Kärkkäinen wrote:
>   
>> On Sat, Mar 21, 2009 at 10:16:52PM +0200, Pasi Kärkkäinen wrote:
>>     
>>>> Also, do you see this problem before you've started any other domains?  
>>>> Or does it only happen once you've run a domU (or only while a domU is 
>>>> running)?
>>>>
>>>>         
>>> I'm not running any other domains.. Only dom0 is running.
>>>
>>> Steps to reproduce this BUG on my pv_ops dom0 testbox:
>>>
>>> 1) Reboot the box to pv_ops dom0 kernel
>>> 2) Login to dom0 via ssh
>>> 3) Start kernel compilation on dom0 (make bzImage && make modules)
>>> 4) Wait some minutes and pv_ops dom0 kernel BUGs
>>>
>>> So no other domains has been or is running when this happens..
>>>
>>> I'll try disabling CONFIG_HIGHPTE now, and see if that makes any difference.
>>>
>>>       
>> CONFIG_HIGHPTE=y and pv_ops dom0 survives up for maybe 30 mins, and then
>> BUGs (during kernel compilation):
>> http://pasik.reaktio.net/xen/pv_ops-dom0-debug/pv_ops-dom0-bootlog-22-xen331-linux-2.6.29-rc8-bug-with-highpte.txt
>>
>>
>> CONFIG_HIGHPTE=n and I get BUG during system startup when udev is started:
>> http://pasik.reaktio.net/xen/pv_ops-dom0-debug/pv_ops-dom0-bootlog-23-xen331-linux-2.6.29-rc8-bug-no-highpte.txt
>>
>> Starting udev: BUG: unable to handle kernel paging request at 70007823
>> IP: [<e30ce245>] pdc_common_ops+0x171/0xfffffcfe [sata_promise]
>> *pdpt = 000000005f781001 
>> Oops: 0002 [#1] SMP 
>>
>> So yeah..  with CONFIG_HIGHPTE=n it seems to happen when sata_promise is loaded.. What should I try next? 
>>
>>     
>
> Actually it's not only sata_promise. I tried 2 more times with the
> CONFIG_HIGHPTE=n pv_ops dom0 kernel:
>
> http://pasik.reaktio.net/xen/pv_ops-dom0-debug/pv_ops-dom0-bootlog-23-xen331-linux-2.6.29-rc8-bug-no-highpte.txt
> http://pasik.reaktio.net/xen/pv_ops-dom0-debug/pv_ops-dom0-bootlog-23-xen331-linux-2.6.29-rc8-bug-no-highpte-2.txt
> http://pasik.reaktio.net/xen/pv_ops-dom0-debug/pv_ops-dom0-bootlog-23-xen331-linux-2.6.29-rc8-bug-no-highpte-3.txt
>
> BUG: unable to handle kernel paging request at a536462c
> IP: [<e30f4278>] classes+0x688/0xfffffa30 [parport]
> *pdpt = 000000005f759001 
> Oops: 0002 [#1] SMP 
>   

Hm, OK.  Something is clearly drastically amiss.  I'll try to repro.

    J