RFR: 8159890: SIGSEGV with UseStringDeduplication and UseSharedSpaces/RequireSharedSpaces

[Per Liden]

Thanks for reviewing Stefan/Derek/Thomas/Jiangli/Ioi.

Thanks for the test Ioi, new webrev with test included:

http://cr.openjdk.java.net/~pliden/8159890/webrev.1/

cheers,
Per

On 2016-06-22 18:20, Ioi Lam wrote:
>
>
> On 6/22/16 9:11 AM, Thomas Schatzl wrote:
>> Hi,
>>
>> On Wed, 2016-06-22 at 16:49 +0200, Per Liden wrote:
>>> Hi,
>>>
>>> Summary: This was bug was introduced by JDK-8150607 - Clean up
>>> CompactHashtable, where the rewrite of CompactHashtable::oops_do()
>>> by
>>> mistake now iterates over entry[0] instead of entry[1] for regular
>>> bucket types. This causes garbage (non-narrowOop) values to be passed
>>> to
>>> the OopClosure passed to oops_do() and we crash. The bug is easy to
>>> reproduce with:
>>>
>>> $ java -Xshare:dump
>>> $ java -XX:+UseSharedSpaces -XX:+UseStringDeduplication -version
>>>
>>> Webrev: http://cr.openjdk.java.net/~pliden/8159890/webrev.0/
>>> Bug: https://bugs.openjdk.java.net/browse/JDK-8159890
>
> Hi Per,
>
> Thanks for finding the bug. Sorry I checked code in without realizing
> that it needed a test case :-(
>
>>    looks good. Not really sure if this needs a regression test. It seems
>> to be too trivial and obvious a fix.
>
> I wrote one anyway :-) I think it's good to have some minimal coverage
> in the test suite to cover future issues.
>
> http://cr.openjdk.java.net/~iklam/jdk9/8159890_cds_strdedup.v02/SharedStringsDedup.java
>
>
> It's a slight modification of
>
> hotspot/test/runtime/SharedArchiveFile/SharedStringsRunAuto.java
>
>
> Thanks
> - Ioi
>
>
>> Thanks,
>>    Thomas
>