AV on SampleProfiler Disable

[brianrob]

• thread Update intro-to-clr.md coreclr#126: tid = 33976, 0x00007ffff6dcf962 libc.so.6`cfree + 34, name = 'dotnet', stop reason = invalid address (fault address: 0xfffffffffffffffc)
  • frame #0: 0x00007ffff6dcf962 libc.so.6cfree + 34 frame dotnet/coreclr#1: 0x00007ffff64771d4 libcoreclr.soCorUnix::CPalObjectBase::~CPalObjectBase(this=0x0000000000729a90) + 52 at palobjbase.cpp:349
    frame Merge changes from TFS coreclr#2: 0x00007ffff6477183 libcoreclr.soCorUnix::CPalObjectBase::ReleaseReference(CorUnix::CPalThread*) [inlined] void CorUnix::InternalDelete<CorUnix::CPalObjectBase>(p=0x0000000000729a90) + 14 at malloc.hpp:134 frame dotnet/coreclr#3: 0x00007ffff6477175 libcoreclr.soCorUnix::CPalObjectBase::ReleaseReference(this=0x0000000000729a90, pthr=0x00007fff4801e9f0) + 117 at palobjbase.cpp:317
    frame Changes to Miscellaneous test project and runtest coreclr#4: 0x00007ffff6468d1b libcoreclr.soCorUnix::CSimpleHandleManager::FreeHandle(this=<unavailable>, pThread=0x00007fff4801e9f0, h=<unavailable>) + 283 at handlemgr.cpp:253 frame dotnet/coreclr#5: 0x00007ffff64687be libcoreclr.soCloseHandle + 70 at handleapi.cpp:312
    frame Add build status badge coreclr#6: 0x00007ffff6468778 libcoreclr.soCloseHandle(hObject=0x0000000000000844) + 40 at handleapi.cpp:287 frame dotnet/coreclr#7: 0x00007ffff61c7530 libcoreclr.soCLREventBase::CloseEvent(this=0x000000000079f6c8) + 112 at synch.cpp:328
    frame Clean up runtest script coreclr#8: 0x00007ffff60d9dca libcoreclr.soThread::~Thread(this=0x000000000079f540) + 234 at threads.cpp:3066 frame dotnet/coreclr#9: 0x00007ffff60da52e libcoreclr.soThread::~Thread(this=0x000000000079f540) + 14 at threads.cpp:2990
    frame Linux release build coreclr#10: 0x00007ffff60d9673 libcoreclr.soThread::DecExternalCount(this=<unavailable>, holdingLock=<unavailable>) + 467 at threads.cpp:2909 frame dotnet/coreclr#11: 0x00007ffff60d8029 libcoreclr.soThread::OnThreadTerminate(this=0x000000000079f540, holdingLock=0) + 1657 at threads.cpp:3541
    frame Add release build badge for linux now that it's working coreclr#12: 0x00007ffff60d7975 libcoreclr.soDestroyThread(th=0x000000000079f540) + 341 at threads.cpp:993 frame dotnet/coreclr#13: 0x00007ffff61acb0f libcoreclr.soSampleProfiler::ThreadProc(args=) + 431 at sampleprofiler.cpp:141
    frame Merge changes from TFS coreclr#14: 0x00007ffff6496562 libcoreclr.soCorUnix::CPalThread::ThreadEntry(pvParam=0x00007fff4801e9f0) + 306 at thread.cpp:1749 frame dotnet/coreclr#15: 0x00007ffff79bd6ba libpthread.so.0start_thread + 202
    frame Fix links to Linux build badge coreclr#16: 0x00007ffff6e5282d libc.so.6`clone + 109

[brianrob]

@kouvel, have you see this before? This is a stress bug that shows up when creating a destroying threads in a loop.

[brianrob]

I think that this may be because COMPlus_PerformanceTracing=1 was set and the test called APIs to enable/disable tracing.

@kouvel, I'm interested in if you've seen this, but if not, I think it might have been a bad combination of the COMPlus variable above and code, and not an issue in threading.

[kouvel]

I haven't seen this before. The object pointer looks wrong, maybe some corruption occurred in the handle table. I don't see anything wrong with the way in which this event is used. I'll need to try for a repro, do you happen to know which test case runs into this, or is it a combination of tests that I can try?

[brianrob]

Thanks @kouvel. Hold off on trying this for the moment. I think that this could have been my own doing. I want to prove that it could be a real bug before you spend any time on it. I'll let you know.

[brianrob]

This appears to have been my fault. Closing.