[PATCH] makedumpfile: fix off-by-one bug in page_to_pfn()

Wen Congyang wency at cn.fujitsu.com
Mon Dec 12 19:36:07 EST 2011


At 12/13/2011 08:21 AM, tachibana at mxm.nes.nec.co.jp Write:
> Hi Wen,
> 
> On 2011/12/12 17:23:59 +0800, Wen Congyang <wency at cn.fujitsu.com> wrote:
>> At 11/24/2011 01:20 PM, Atsushi Kumagai Write:
>>> Hi Wen,
>>>
>>> Thank you for the patch. 
>>> I will check it.
>>
>> Hi, kumagai
>>
>> do you have any comment for this patch?
> 
> Sorry for late reply.
> I will merge your fix to the next makedumpfile. By the way, did you 
> detect this problem only by source program? Or by result of makedumpfile?
> If there is no problem, please let me know it.

By result of makedumpfile. I find some pages are still in vmcore.

Thanks
Wen Congyang

> 
> Thanks
> tachibana
> 
> 
>>
>> Thanks
>> Wen Congyang
>>
>>>
>>> Thanks
>>> Kumagai
>>>
>>>
>>> On Wed, 23 Nov 2011 13:53:51 +0800
>>> Wen Congyang <wency at cn.fujitsu.com> wrote:
>>>
>>>> The pfn region in a mmd is [mmd->pfn_start, mmd->pfn_end).
>>>> So the max index should be mmd->pfn_end - mmd->pfn_start -1.
>>>> If index >=(not >) mmd->pfn_end - mmd->pfn_start, we should check
>>>> the next mmd.
>>>>
>>>> Signed-off-by: Wen Congyang <wency at cn.fujitsu.com>
>>>>
>>>> ---
>>>>  makedumpfile.c |    2 +-
>>>>  1 files changed, 1 insertions(+), 1 deletions(-)
>>>>
>>>> diff --git a/makedumpfile.c b/makedumpfile.c
>>>> index 7b7c266..db8e53f 100644
>>>> --- a/makedumpfile.c
>>>> +++ b/makedumpfile.c
>>>> @@ -2879,7 +2879,7 @@ page_to_pfn(unsigned long page)
>>>>  		if (page < mmd->mem_map)
>>>>  			continue;
>>>>  		index = (page - mmd->mem_map) / SIZE(page);
>>>> -		if (index > mmd->pfn_end - mmd->pfn_start)
>>>> +		if (index >= mmd->pfn_end - mmd->pfn_start)
>>>>  			continue;
>>>>  		pfn = mmd->pfn_start + index;
>>>>  		break;
>>>> -- 
>>>> 1.7.1
>>>
>>> _______________________________________________
>>> kexec mailing list
>>> kexec at lists.infradead.org
>>> http://lists.infradead.org/mailman/listinfo/kexec
>>>
>>
>>
>> _______________________________________________
>> kexec mailing list
>> kexec at lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/kexec
> 




More information about the kexec mailing list