Re: /proc/kcore has a unreasonable size(281474974617600) in x86_64 2.6.30-rc8.

Tao Ma
2009-06-08T08:02:38Z

Américo Wang wrote:
> On Mon, Jun 8, 2009 at 2:02 PM, Tao Ma<tao.ma@oracle.com> wrote:
>>
>> Amerigo Wang wrote:
>>> On Sat, Jun 06, 2009 at 03:21:23PM -0700, Yinghai Lu wrote:
>>>> Tao Ma wrote:
>>>>> Yinghai Lu wrote:
>>>>>> Tao Ma wrote:
>>>>>>> Amerigo Wang wrote:
>>>>>>>> On Fri, Jun 05, 2009 at 05:30:49PM +0800, Tao Ma wrote:
>>>>>>>>>> Please send the boot logs: dmesg -s 1000000 > foo
>>>>>>>>> attached.
>>>>>>>>> #######high memory 18446612137615818752, size_t 18446612137615818752
>>>>>>>>> #######kcore size 5301604352, PAGE_OFFSET 0, PAGE_SIZE 4096
>>>>>>>> These two lines must be added by yourself...
>>>>>>>>
>>>>>>>> What?!
>>>>>>>> How can PAGE_OFFSET be 0??
>>>>>>>> Can you show us these two printk() you just added?
>>>>>>>>
>>>>>>>> And, the size of kcore is not the crazy number in the subject...
>>>>>>>> This one is much saner..
>>>>>>> Sorry, I used the wrong printk. the correct one is:
>>>>>>> #######high memory 18446612137615818752, size_t 18446612137615818752
>>>>>>> #######kcore size 5301604352, PAGE_OFFSET 18446612132314218496,
>>>>>>> PAGE_SIZE 4096
>>>>>>>
>>>>>> %lx should be used.
>>>>>>
>>>>>> also you compiler doesn't like
>>>>>>
>>>>>> high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
>>>>>>
>>>>>> in setup.c?
>>>>> Sorry fo my poor English, bug what do you mean?
>>>>>
>>>>> I just printk in the setup.c and the result is
>>>>>
>>>>> @@@@high_momory ffff88013c000000
>>>> so that value print out is right.
>>> Yeah.
>>>
>>> Tao, can you reproduce the number mentioned in the subject??
>> Sorry for the delay.
>>
>> But the result is the same
>
> Yes?
> Your printk() shows kcore size is: 5301604352, and in your subject it is
> 281474974617600...
>
> Or they happened in the same time?
yes. the same box and the same linux version.
A bit strange.

[taoma@ocfs2-test2 ~]$ dmesg|grep "high memory"
high memory ffff88013c000000, size 5301604352
[taoma@ocfs2-test2 ~]$ ll /proc/kcore
-r-------- 1 root root 281474974617600 Jun 8 15:20 /proc/kcore

Regards,
Tao