BUG: withOwnerThread closes MappedMemorySegment

[Maurizio Cimadamore]

The fix Jorn has identified has now been pushed. Would be helpful, if 
you can, to get the latest panama code, and give your app another try, 
to see if the crash is still there when intrinsics are enabled.

Thanks
Maurizio

On 25/09/2020 21:19, Ty Young wrote:
> Forgot to mention, I'm using default GC.
>
>
> On 9/25/20 10:00 AM, Jorn Vernee wrote:
>> Hi Ty,
>>
>> I'm trying to reproduce your crash locally, but no luck so far. From 
>> the error message, it seems like it might be caused by a thread being 
>> suspended while inside a native call, which triggers a slow path that 
>> seems to have a bug in it; not setting the thread state to 
>> _thread_in_java again.
>>
>> The following patch fixes that mistake [1], but since I'm not able so 
>> far to reproduce the crash I can't say for sure that that will fix 
>> the problem you are seeing.
>>
>> It would help if you could provide some steps to reproduce, and/or 
>> try out the patch at [1] if you can (should be enough to put it in a 
>> file and then use `git apply <file>`).
>>
>> I'm also curious to know if you are running with the default GC, or 
>> maybe another one?
>>
>> Thanks,
>> Jorn
>>
>> [1] :
>>
>> diff --git a/src/hotspot/cpu/x86/sharedRuntime_x86_64.cpp 
>> b/src/hotspot/cpu/x86/sharedRuntime_x86_64.cpp
>> index 51b9082cfae..887369fc5c8 100644
>> --- a/src/hotspot/cpu/x86/sharedRuntime_x86_64.cpp
>> +++ b/src/hotspot/cpu/x86/sharedRuntime_x86_64.cpp
>> @@ -3810,11 +3810,12 @@ void NativeInvokerGenerator::generate() {
>>    __ safepoint_poll(L_safepoint_poll_slow_path, r15_thread, rscratch1);
>>    __ cmpl(Address(r15_thread, JavaThread::suspend_flags_offset()), 0);
>>    __ jcc(Assembler::notEqual, L_safepoint_poll_slow_path);
>> -  // change thread state
>> -  __ movl(Address(r15_thread, JavaThread::thread_state_offset()), 
>> _thread_in_Java);
>>
>>    __ bind(L_after_safepoint_poll);
>>
>> +  // change thread state
>> +  __ movl(Address(r15_thread, JavaThread::thread_state_offset()), 
>> _thread_in_Java);
>> +
>>    __ block_comment("reguard stack check");
>>    Label L_reguard;
>>    Label L_after_reguard
>>