RFR(s): 8152182: Possible overflow in initialzation of _rescan_task_size and _marking_task_size

sangheon sangheon.kim at oracle.com
Tue Apr 5 21:25:29 UTC 2016


Thank you, Jesper.

Sangheon


On 04/05/2016 02:24 PM, Jesper Wilhelmsson wrote:
> Looks good!
> /Jesper
>
> Den 5/4/16 kl. 23:19, skrev sangheon:
>> Hi all,
>>
>> After some discussion with Jesper, I updated below:
>> 1. Removed a flag value recommendation part. Maybe we need more tests 
>> on various
>> machines and this way is mostly exception comparing to other flags' 
>> handling. So
>> removing it.
>> 2. Changed comments 'would' -> 'could'.
>>
>> Updated webrev:
>> http://cr.openjdk.java.net/~sangheki/8152182/webrev.01_to_00
>> http://cr.openjdk.java.net/~sangheki/8152182/webrev.01_to_00
>>
>> Thanks,
>> Sangheon
>>
>>
>> On 04/05/2016 10:24 AM, sangheon wrote:
>>> Hi all,
>>>
>>> Please review this change for CMSRescanMultiple and 
>>> CMSConcMarkMultiple flags.
>>>
>>> Both flags are set by "CardTableModRefBS::card_size_in_words * 
>>> BitsPerWord *
>>> flag" which potentially would make an overflow with their maximum value
>>> without setting range. And these flags also would make an arithmetic 
>>> overflow
>>> when calculating with the size and the start address of reserved 
>>> area. In
>>> addition, CMSRescanMultiple needs an alignment check.
>>>
>>> CR: https://bugs.openjdk.java.net/browse/JDK-8152182
>>> Webrev: http://cr.openjdk.java.net/~sangheki/8152182/webrev.00
>>> Testing: JPRT, runtime/commandline JTREG for all platforms
>>>
>>> Thanks,
>>> Sangheon
>>



More information about the hotspot-gc-dev mailing list