Hotspot crash compiling sun.invoke.util.ValueConversions::identity

[Vladimir Ivanov]

Thanks, Eirik!

> I have an hs_err file ready with a corresponding core dump file (176MB).
>
> I'll zip these up and send a download link to you off-list.
>
> Let me know if there is a better way to manage these files. Should we
> have a Jira issue to track progress?
Yes, I plan to file one once I make sure it's not a duplicate.

Best regards,
Vladimir Ivanov

>
> Thanks,
> Eirik.
>
> On Mon, Mar 2, 2015 at 4:01 PM, Vladimir Ivanov
> <vladimir.x.ivanov at oracle.com> wrote:
>> Eirik,
>>
>> Thanks for the report!
>>
>> As a first step, I'd like to see corresponding hotspot crash log
>> (hs_err_pid*.log).
>>
>> It seems you stepped on a bug in invokedynamic implementation (lambdas are
>> translated into indy calls on bytecode level) which happens when it is
>> initialized too early in VM lifecycle (e.g. java agent premain).
>>
>> I'd be grateful for a stand-alone test case (focus on premain method logic)
>> or steps how to reproduce it myself.
>>
>> Best regards,
>> Vladimir Ivanov
>>
>> On 3/2/15 4:10 AM, Eirik Bjørsnøs wrote:
>>>
>>> Ladies and gentlemen,
>>>
>>> Last week, some of the world's brightest, most capable and all round
>>> good looking Java developers gathered in Crested Butte, Colorado for
>>> the Winter Tech Forum (WTF) 2015 [1].
>>>
>>> Wednesday was Hackathon Day, and a group of us decided to embark the
>>> adventure of creating a live Java code coverage engine called Skybar
>>> [2].
>>>
>>> We made good progress and by the afternoon we knew we'd have something
>>> good to show at the 8pm showcase. So we confidently headed over to
>>> Ryce Asian Bistro [3] at 17:30 for a nice team dinner.
>>>
>>> Luckily we went easy on the saké, because when we came back to
>>> finalise our demo, we found that Hotspot had crashed:
>>>
>>> # A fatal error has been detected by the Java Runtime Environment:
>>> #
>>> #  SIGBUS (0xa) at pc=0x000000012a6d61e6, pid=10738, tid=18691
>>> [..]
>>> Compiled method (c2)  152453 1542       4
>>> sun.invoke.util.ValueConversions::identity (2 bytes)
>>>
>>> Shock, horror! Our demo was just minutes away, would we be able to
>>> present? Our team immediately went into debugging mode:
>>>
>>> Could we reproduce without using our -javaagent? No. Was the crash
>>> consistently reproducible? Kind of, but we had to stress test our
>>> code. Was there a any consistency in the hs_err reports? Yes, it
>>> seemed to always involve lambda expressions in out agent code.
>>>
>>> The team decided we had to remove all lambdas from our agent code in
>>> the hope that would improve the situation. And it did! At 7:50 PM, we
>>> had a stable build and ran out to make it to the presentations.
>>>
>>> Skybar was very well received. Our demo worked. Nothing crashed.
>>> Applause and shouts of "Ship it!" was heard from the audience. It was
>>> good times. We headed over to the Princess Wine Bar [4] for some
>>> celebratory drinks.
>>>
>>> The team is continuing our work on Skybar. But we miss our lamdas, and
>>> we want them back! To achieve this, we need help from the Hotspot
>>> team. On our side, we are willing to  work with you try to make
>>> reproducible test cases and collect any other useful information.
>>>
>>> What would be the best next step in saving Lambas on Agents? We would
>>> love to help out fixing this. Should we file an issue somewhere and
>>> upload our hs_err file(s)?
>>>
>>> On behalf of the Skybar team -
>>> Eirik,
>>>
>>> [1] http://www.mindviewinc.com/Conferences/JavaPosseRoundup/
>>> [2] https://github.com/WinterTechForum/skybar
>>> [3] http://www.ryceasianbistro.com
>>> [4] https://www.facebook.com/princesswinebar
>>>
>>