Bug 46933 – old-run-webkit-tests deadlocks on fast/forms/box-shadow-override.html on leopard commit-bot

• Component: Tools / Tests
• Status: RESOLVED INVALID

[Eric Seidel (no email)]

old-run-webkit-tests deadlocked on leopard commit-bot

old-run-webkit-tests seems blocked in read:


Analysis of sampling perl (pid 64922) every 1 millisecond
Call graph:
    8823 Thread_2507
      8823 0x1ee6
        8823 0x204e
          8823 perl_run
            8823 Perl_runops_standard
              8823 Perl_do_readline
                8823 Perl_sv_gets
                  8823 PerlIO_getc
                    8823 PerlIOStdio_read
                      8823 fgetc
                        8823 __srget
                          8823 __srefill
                            8823 read
                              8823 read

Total number in stack (recursive counted multiple, when >=5):

Sort by top of stack, same collapsed (when >= 5):
        read        8823


As does DumpRenderTree:


Analysis of sampling DumpRenderTree (pid 65489) every 1 millisecond
Call graph:
    6206 Thread_2907
      6206 start
        6206 main
          6206 dumpRenderTree(int, char const**)
            6206 fgets
              6206 __srefill
                6206 read
                  6206 read
    6206 Thread_2a03
      6206 thread_start
        6206 _pthread_start
          6206 __NSThread__main__
            6206 -[NSThread main]
              6206 +[NSURLConnection(NSURLConnectionReallyInternal) _resourceLoadLoop:]
                6206 CFRunLoopRunInMode
                  6206 CFRunLoopRunSpecific
                    6206 mach_msg
                      6206 mach_msg_trap
                        6206 mach_msg_trap
    6206 Thread_2b03
      6206 thread_start
        6206 _pthread_start
          6206 CFURLCacheWorkerThread(void*)
            6206 CFRunLoopRunInMode
              6206 CFRunLoopRunSpecific
                6206 mach_msg
                  6206 mach_msg_trap
                    6206 mach_msg_trap
    6206 Thread_2c03
      6206 thread_start
        6206 _pthread_start
          6206 WTF::TCMalloc_PageHeap::runScavengerThread(void*)
            6206 WTF::TCMalloc_PageHeap::scavengerThread()
              6206 pthread_cond_wait$UNIX2003
                6206 __semwait_signal
                  6206 __semwait_signal
    6206 Thread_2d03
      6206 thread_start
        6206 _pthread_start
          6206 ReadSchedulerThreadEntryPoint
            6206 TSWaitOnSemaphoreCommon
              6206 TSWaitOnConditionTimedRelative
                6206 pthread_cond_timedwait_relative_np
                  6206 _pthread_cond_wait
                    6206 semaphore_timedwait_signal_trap
                      6206 semaphore_timedwait_signal_trap
    6206 Thread_2e03
      6206 thread_start
        6206 _pthread_start
          6206 CAPThread::Entry(CAPThread*)
            6206 HALRunLoop::OwnThread(void*)
              6206 CFRunLoopRunInMode
                6206 CFRunLoopRunSpecific
                  6206 mach_msg
                    6206 mach_msg_trap
                      6206 mach_msg_trap
    6206 Thread_2f03
      6206 thread_start
        6206 _pthread_start
          6206 select$DARWIN_EXTSN
            6206 select$DARWIN_EXTSN
    6206 Thread_3003
      6206 thread_start
        6206 _pthread_start
          6206 glvmDoWork
            6206 pthread_cond_wait$UNIX2003
              6206 __semwait_signal
                6206 __semwait_signal

Total number in stack (recursive counted multiple, when >=5):
        7       _pthread_start
        7       thread_start

Sort by top of stack, same collapsed (when >= 5):
        mach_msg_trap        18618
        __semwait_signal        12412
        read        6206
        select$DARWIN_EXTSN        6206
        semaphore_timedwait_signal_trap        6206

[Eric Seidel (no email)]

The test it was hung on was:

fast/forms/box-shadow-override.html

We don't run pixel tests on the commit-queue.

[Eric Seidel (no email)]

It was attempting to land  patch 69139 from bug 46767

[Eric Seidel (no email)]

Same hang again:


Analysis of sampling DumpRenderTree (pid 43418) every 1 millisecond
Call graph:
    6236 Thread_2907
      6236 start
        6236 main
          6236 dumpRenderTree(int, char const**)
            6236 fgets
              6236 __srefill
                6236 read
                  6236 read

Analysis of sampling perl (pid 41600) every 1 millisecond
Call graph:
    8973 Thread_2907
      8973 0x1ee6
        8973 0x204e
          8973 perl_run
            8973 Perl_runops_standard
              8973 Perl_do_readline
                8973 Perl_sv_gets
                  8973 PerlIO_getc
                    8973 PerlIOStdio_read
                      8973 fgetc
                        8973 __srget
                          8973 __srefill
                            8973 read
                              8973 read

Same test hung too!

fast/forms/box-shadow-override.html -> crashed

[Eric Seidel (no email)]

It was attempting to land patch 69403 from bug 46946 in this second hang.

This does not happen every time.  Just often. :)  We've seen hangs on the Leopard commit bot for months, but only recently have I been trying to investigate why.  It's possible they've always been this same hang.

[Eric Seidel (no email)]

I don't see anything in http://trac.webkit.org/browser/trunk/LayoutTests/fast/forms/box-shadow-override.html which would suggest why its deadlocking on that test.

[Eric Seidel (no email)]

Note the -> crashed above, is because I killed DumpRenderTree.  Not because fast/forms/box-shadow-override.html crashed.  DRT deadlocked while processing fast/forms/box-shadow-override.html.

We've not yet seen this hang on either of the Snow Leoaprd commit-queue bots.

[Eric Seidel (no email)]

We still continue to hit this bug on the leopard commit bot.  Adam suggests that it's probably a test just before this one which is causing DRT to get off like this.

[Ahmad Saleem]

Is `old-run-webkit-tests` still in use or we can close this?

[Sam Sneddon [:gsnedders]]

Removed in bug 135374 nearly a decade ago. 🙃