RFR: 8185529: JCK api/java_lang/Object/WaitTests failed with jdk10/hs nightly

[David Holmes]

Thanks Calvin!

David

On 9/10/2017 1:26 PM, Calvin Cheung wrote:
> Hi David,
> 
> I've tried your fix and the test passed with it.
> 'r'eviewed.
> 
> thanks,
> Calvin
> 
> On 10/8/17, 6:35 PM, David Holmes wrote:
>> Can I get a second review please.
>>
>> Thanks,
>> David
>>
>> On 7/10/2017 9:28 AM, David Holmes wrote:
>>> Thanks Dan!
>>>
>>> David
>>>
>>> On 6/10/2017 11:58 PM, Daniel D. Daugherty wrote:
>>>> Thumbs up!
>>>>
>>>> Dan
>>>>
>>>>
>>>> On 10/5/17 10:47 PM, David Holmes wrote:
>>>>> Bug is not public - sorry.
>>>>>
>>>>> webrev: http://cr.openjdk.java.net/~dholmes/8185529/webrev/
>>>>>
>>>>> Also patch inline below.
>>>>>
>>>>> Problem: o.wait(Long.MAX_VALUE) returns immediately
>>>>>
>>>>> Cause: arithmetic overflow gives a time in the past so the timeout 
>>>>> expires immediately
>>>>>
>>>>> This was introduced by the fix for:
>>>>>
>>>>> https://bugs.openjdk.java.net/browse/JDK-8174231 "Factor out and 
>>>>> share PlatformEvent and Parker code for POSIX systems."
>>>>>
>>>>> while we go to great lengths to ensure we avoid overflows inside 
>>>>> the time calculation functions, I overlooked the fact that we now 
>>>>> first convert a millisecond value into nanoseconds, which can 
>>>>> overflow.
>>>>>
>>>>> Fix: limit the millis value to the existing hard limit of 
>>>>> MAX_SECS*MILLIUNITS ms. That can not overflow when converted to nanos.
>>>>>
>>>>> Thanks,
>>>>> David
>>>>> -----
>>>>>
>>>>> --- old/src/hotspot/os/posix/os_posix.cpp    2017-10-06 
>>>>> 00:34:31.595159338 -0400
>>>>> +++ new/src/hotspot/os/posix/os_posix.cpp    2017-10-06 
>>>>> 00:34:29.443037883 -0400
>>>>> @@ -1770,6 +1770,12 @@
>>>>>
>>>>>    if (v == 0) { // Do this the hard way by blocking ...
>>>>>      struct timespec abst;
>>>>> +    // We have to watch for overflow when converting millis to nanos,
>>>>> +    // but if millis is that large then we will end up limiting to
>>>>> +    // MAX_SECS anyway, so just do that here.
>>>>> +    if (millis / MILLIUNITS > MAX_SECS) {
>>>>> +      millis = jlong(MAX_SECS) * MILLIUNITS;
>>>>> +    }
>>>>>      to_abstime(&abst, millis * (NANOUNITS / MILLIUNITS), false);
>>>>