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

Américo Wang
2009-06-05T09:17:37Z

Add some Cc: to x86 people. :)

Yinghai?

On Fri, Jun 5, 2009 at 4:57 PM, Tao Ma<tao.ma@oracle.com> wrote:
>
>
> Amerigo Wang wrote:
>>
>> On Fri, Jun 05, 2009 at 02:59:46PM +0800, Tao Ma wrote:
>>>
>>> Andrew Morton wrote:
>>>>
>>>> On Fri, 05 Jun 2009 12:03:52 +0800 Tao Ma <tao.ma@oracle.com> wrote:
>>>>
>>>>> Hi list,
>>>>>       In 2.6.30-rc8, /proc/kcore in x86_64's size is unreasonable large
>>>>> to be 281474974617600.
>>>>> While in a x86 box, it is 931131392 which looks sane.
>>>>>
>>>>> [root@test8 ~]# ll /proc/kcore
>>>>> -r-------- 1 root root 281474974617600 Jun  5 11:15 /proc/kcore
>>>>>
>>>>> [root@ocfs2-test9 ~]$ ll /proc/kcore
>>>>> -r-------- 1 root root 931131392 Jun  5 11:58 /proc/kcore
>>>>>
>>>>> I just noticed this when kexec fails in "Can't find kernel text map
>>>>> area from kcore".
>>>>>
>>>>> Is there something wrong?
>>>>>
>>>> fs/proc/kcore.c hasn't changed since October last year.  Was 2.6.29 OK?
>>>> Earlier kernels?
>>>
>>> with 2.6.29, ls shows the same output.
>>> [root@test8 ~]# ll /proc/kcore
>>> -r-------- 1 root root 281474974617600 Jun  5 14:35 /proc/kcore
>>
>>
>> Thanks.
>>
>> It looks like the value of 'high_memory' is insane..
>> Can you get its value on your machine? You can add a printk() or use
>> systemtap etc..
>
> Just did that.
> Also a strange number.
> high memory 18446612137615818752.
>
> Regards,
> Tao
>