RFR: JDK-8209389: SIGSEGV in WalkOopAndArchiveClosure::do_oop_work

[Jiangli Zhou]

Thanks!

Jiangli


On 8/16/18 10:49 AM, Ioi Lam wrote:
> Looks good. Thanks!
>
> - Ioi
>
>
> On 8/15/18 5:45 PM, Jiangli Zhou wrote:
>> Here is the updated webrev: 
>> http://cr.openjdk.java.net/~jiangli/8209389/webrev.01/.
>>
>> Thanks,
>>
>> Jiangli
>>
>>
>> On 8/14/18 9:34 PM, Jiangli Zhou wrote:
>>> Hi Ioi,
>>>
>>> Thanks for the review and suggestions. I'll incorporate them.
>>>
>>> Thanks,
>>>
>>> Jiangli
>>>
>>>
>>> On 8/14/18 6:05 PM, Ioi Lam wrote:
>>>> Hi Jiangli,
>>>>
>>>> The changes look good. I think it's OK to exit the dumping VM 
>>>> because normally we should not be archiving such large objects.
>>>>
>>>> For the various messages, I think we should include the object size 
>>>> (in bytes).
>>>>
>>>> Also, for this message:
>>>>
>>>>  395       if (archived == NULL) {
>>>>  396         ResourceMark rm;
>>>>  397         tty->print("Failed to archive %s object " PTR_FORMAT " 
>>>> in sub-graph",
>>>>  398                    obj->klass()->external_name(), p2i(obj));
>>>>  399         vm_exit(1);
>>>>  400       }
>>>>
>>>> In addition to the size, I think we should also add 
>>>> obj->print_on(tty) to help diagnosing the problems.
>>>>
>>>> Thanks
>>>>
>>>> - Ioi
>>>>
>>>> On 8/14/18 5:50 PM, Jiangli Zhou wrote:
>>>>> Please review the following fix that addresses the issue for 
>>>>> JDK-8209389. A Java object that's larger than one GC region cannot 
>>>>> be archived as we currently don't support object spanning more 
>>>>> than one archive heap region. The archiving code needs to check 
>>>>> the MetaspaceShared::archive_heap_object return value and handle 
>>>>> failure accordingly. Thanks Claes for finding the edge case and 
>>>>> reporting the problem!
>>>>>
>>>>>   webrev: http://cr.openjdk.java.net/~jiangli/8209389/webrev.00
>>>>>
>>>>>   bug: https://bugs.openjdk.java.net/browse/JDK-8209389
>>>>>
>>>>> - java_lang_Class::archive_basic_type_mirrors
>>>>>   Archived object returned by MetaspaceShared::archive_heap_object 
>>>>> should not be NULL in these cases (basic type mirrors are not 
>>>>> humongous). Added an assert.
>>>>>
>>>>> - HeapShared::archive_reachable_objects_from_static_field
>>>>>   If the sub-graph entry object is too large, archiving is skipped 
>>>>> for it’s referenced sub-graph and dumping process continues.
>>>>>
>>>>> - WalkOopAndArchiveClosure::do_oop_work
>>>>>   Abort dumping when archiving failures due to extra-large object 
>>>>> encountered during the sub-graph archiving.
>>>>>
>>>>> Tested with the new test case included in the webrev. Tier1 - 
>>>>> tier4 testing are in progress.
>>>>>
>>>>> Thanks,
>>>>> Jiangli
>>>>
>>>
>>
>