JVM crash in ShenandoahInitMarkRootsClosure

[Omar Kilani]

Hi Roman,

I’ll try and let you know. It kind of ran fine for a week or so before the
various crashes.

There was another change that I saw that seemed related to this but can’t
find it easily on my phone.

Anyway, will report back. :)

Regards,
Omar
On Wed, Mar 27, 2019 at 11:48 AM Roman Kennke <rkennke at redhat.com> wrote:

> It's hard to say. Does it happen without -XX:+UseStringDeduplication ?
> JDK-8221278 is only relevant with string deduplication explicitely
> turned on.
>
> Roman
>
> > We also see:
> >
> > ---------------  T H R E A D  ---------------
> > Current thread (0x00007fa0ac192800):  GCTaskThread "Shenandoah GC
> > Threads#9" [stack: 0x00007fa08d1f6000,0x00007fa08d2f6000] [id=10523]
> >
> > Stack: [0x00007fa08d1f6000,0x00007fa08d2f6000],
> > sp=0x00007fa08d2f4520,  free space=1017k
> >
> > Native frames: (J=compiled Java code, A=aot compiled Java code,
> > j=interpreted, Vv=VM code, C=native code)
> >
> > V  [libjvm.so+0xd6ccd8]  void
> >
> ShenandoahHeap::marked_object_iterate<ShenandoahObjectToOopClosure<ShenandoahUpdateHeapRefsClosure
> > (ShenandoahHeapRegion*,
> > ShenandoahObjectToOopClosure<ShenandoahUpdateHeapRefsClosure>*,
> > HeapWord*)+0x288
> > V  [libjvm.so+0xd6d54d]
> >
> ShenandoahUpdateHeapRefsTask<ShenandoahUpdateHeapRefsClosure>::do_work()+0xad
> > V  [libjvm.so+0xd6d70c]
> >
> ShenandoahUpdateHeapRefsTask<ShenandoahUpdateHeapRefsClosure>::work(unsigned
> > int)+0x5c
> > V  [libjvm.so+0xf565bd]  GangWorker::loop()+0x4d
> > V  [libjvm.so+0xec2b35]  Thread::call_run()+0x75
> > V  [libjvm.so+0xc000ce]  thread_native_entry(Thread*)+0xee
> >
> > siginfo: si_signo: 11 (SIGSEGV), si_code: 1 (SEGV_MAPERR), si_addr:
> > 0x00007fa4af6422a0
> >
> > --
> >
> > In a different app. Is this the same bug, or a different thing?
> >
> > Thanks!
> >
> > Regards,
> > Omar
> >
> > On Wed, Mar 27, 2019 at 11:39 AM Roman Kennke <rkennke at redhat.com>
> wrote:
> >>
> >> Hi Omar,
> >>
> >> yes, that seems very likely. The fix should appear in nightlies very
> soon.
> >>
> >> Thanks, Roman
> >>
> >>
> >>> Hi there,
> >>>
> >>> We're testing:
> >>>
> >>> OpenJDK 64-Bit Server VM
> >>> (12-testing+0-builds.shipilev.net-openjdk-jdk12-b140-20190320-jdk-1233)
> >>>
> >>> And had a crash in one of our applications:
> >>>
> >>> ---------------  T H R E A D  ---------------
> >>> Current thread (0x00007febe8156000):  GCTaskThread "Shenandoah GC
> >>> Threads#5" [stack: 0x00007febec68a000,0x00007febec78a000] [id=2927]
> >>> Stack: [0x00007febec68a000,0x00007febec78a000],
> >>> sp=0x00007febec788ae0,  free space=1018k
> >>>
> >>> Native frames: (J=compiled Java code, A=aot compiled Java code,
> >>> j=interpreted, Vv=VM code, C=native code)
> >>>
> >>> V  [libjvm.so+0xd24b2d]
> >>> ShenandoahInitMarkRootsClosure<(UpdateRefsMode)0,
> >>> (StringDedupMode)1>::do_oop(oopDesc**)+0x7d
> >>> V  [libjvm.so+0xd7c6c6]
> >>>
> ShenandoahStrDedupQueue::unlink_or_oops_do_impl(StringDedupUnlinkOrOopsDoClosure*,
> >>> unsigned long)+0x96
> >>> V  [libjvm.so+0xe09aa3]
> >>>
> StringDedupQueue::unlink_or_oops_do(StringDedupUnlinkOrOopsDoClosure*)+0x43
> >>> V  [libjvm.so+0xd7d3e8]
> >>> ShenandoahStringDedup::parallel_oops_do(OopClosure*, unsigned
> >>> int)+0x58
> >>> V  [libjvm.so+0xd7b4f1]
> >>> ShenandoahRootProcessor::process_vm_roots(OopClosure*, OopClosure*,
> >>> OopClosure*, unsigned int)+0x111
> >>> V  [libjvm.so+0xd7b87a]
> >>> ShenandoahRootProcessor::process_all_roots(OopClosure*, OopClosure*,
> >>> CLDClosure*, CodeBlobClosure*, ThreadClosure*, unsigned int)+0x7a
> >>> V  [libjvm.so+0xd19000]
> >>> ShenandoahInitMarkRootsTask<(UpdateRefsMode)0>::work(unsigned
> >>> int)+0x200
> >>> V  [libjvm.so+0xf565bd]  GangWorker::loop()+0x4d
> >>> V  [libjvm.so+0xec2b35]  Thread::call_run()+0x75
> >>> V  [libjvm.so+0xc000ce]  thread_native_entry(Thread*)+0xee
> >>>
> >>> siginfo: si_signo: 11 (SIGSEGV), si_code: 128 (SI_KERNEL), si_addr:
> >>> 0x0000000000000000
> >>>
> >>> --
> >>>
> >>> Is this fixed by:
> >>>
> >>> https://bugs.openjdk.java.net/browse/JDK-8221278
> >>>
> >>> ? :)
> >>>
> >>> Thanks!
> >>>
> >>> Regards,
> >>> Omar
> >>>
> >>
>