Software Diagnostics Institute

We continue extending our memory analysis pattern language to Python execution environment after introducing Managed Stack Trace variant. Now we add Runtime Thread (former CLR Thread memory analysis pattern) variant. For Linux and GDB, in the case of Reduced Symbolic Information we get this stack trace:


(gdb) bt
#0 0x00007ffff7caeb97 in __GI___select (nfds=0, readfds=0x0, writefds=0x0, exceptfds=0x0, timeout=0x7fffffffd9f0)
at ../sysdeps/unix/sysv/linux/select.c:41
#1 0x00000000004e8965 in ?? ()
#2 0x00000000005d8711 in _PyMethodDef_RawFastCallKeywords ()
#3 0x000000000054b330 in ?? ()
#4 0x00000000005524cd in _PyEval_EvalFrameDefault ()
#5 0x00000000005d91fc in _PyFunction_FastCallKeywords ()
#6 0x000000000054e5ac in _PyEval_EvalFrameDefault ()
#7 0x00000000005d91fc in _PyFunction_FastCallKeywords ()
#8 0x000000000054e5ac in _PyEval_EvalFrameDefault ()
#9 0x00000000005d91fc in _PyFunction_FastCallKeywords ()
#10 0x000000000054e5ac in _PyEval_EvalFrameDefault ()
#11 0x000000000054bcc2 in _PyEval_EvalCodeWithName ()
#12 0x000000000054e0a3 in PyEval_EvalCode ()
#13 0x0000000000630ce2 in ?? ()
#14 0x0000000000630d97 in PyRun_FileExFlags ()
#15 0x00000000006319ff in PyRun_SimpleFileExFlags ()
#16 0x000000000065432e in ?? ()
#17 0x000000000065468e in _Py_UnixMain ()
#18 0x00007ffff7be209b in __libc_start_main (main=0x4bc560 <main>, argc=2, argv=0x7fffffffe4c8, init=<optimized out>, fini=<optimized out>,
rtld_fini=<optimized out>, stack_end=0x7fffffffe4b8) at ../csu/libc-start.c:308
#19 0x00000000005e0e8a in _start ()


If we install python debug package (for example, python3.7-dbg) we get full symbolic information:


(gdb) bt
#0 0x00007ffff7caeb97 in __GI___select (nfds=0, readfds=0x0, writefds=0x0, exceptfds=0x0, timeout=0x7fffffffd9f0)
at ../sysdeps/unix/sysv/linux/select.c:41
#1 0x00000000004e8965 in pysleep (secs=<optimized out>) at ../Modules/timemodule.c:1829
#2 time_sleep (self=<optimized out>, obj=<optimized out>, self=<optimized out>, obj=<optimized out>) at ../Modules/timemodule.c:371
#3 0x00000000005d8711 in _PyMethodDef_RawFastCallKeywords (method=0x82dbe0 <time_methods+288>, self=<module at remote 0x7ffff77d5c28>,
args=0x7ffff788c550, nargs=<optimized out>, kwnames=<optimized out>) at ../Objects/call.c:644
#4 0x000000000054b330 in _PyCFunction_FastCallKeywords (kwnames=<optimized out>, nargs=<optimized out>, args=0x7ffff788c550,
func=<built-in method sleep of module object at remote 0x7ffff77d5c28>) at ../Objects/call.c:730
#5 call_function (pp_stack=0x7fffffffdb60, oparg=<optimized out>, kwnames=<optimized out>) at ../Python/ceval.c:4568
#6 0x00000000005524cd in _PyEval_EvalFrameDefault (f=<optimized out>, throwflag=<optimized out>) at ../Python/ceval.c:3093
#7 0x00000000005d91fc in PyEval_EvalFrameEx (throwflag=0, f=Frame 0x7ffff788c3d8, for file sleepLoop.py, line 11, in bar ()) at ../Python/ceval.c:547
#8 function_code_fastcall (globals=<optimized out>, nargs=<optimized out>, args=<optimized out>, co=<optimized out>) at ../Objects/call.c:283
#9 _PyFunction_FastCallKeywords (func=<optimized out>, stack=<optimized out>, nargs=<optimized out>, kwnames=<optimized out>) at ../Objects/call.c:408
#10 0x000000000054e5ac in call_function (kwnames=0x0, oparg=<optimized out>, pp_stack=<synthetic pointer>) at ../Python/ceval.c:4616
#11 _PyEval_EvalFrameDefault (f=<optimized out>, throwflag=<optimized out>) at ../Python/ceval.c:3124
#12 0x00000000005d91fc in PyEval_EvalFrameEx (throwflag=0, f=Frame 0x7ffff77d85e8, for file sleepLoop.py, line 7, in foo ()) at ../Python/ceval.c:547
#13 function_code_fastcall (globals=<optimized out>, nargs=<optimized out>, args=<optimized out>, co=<optimized out>) at ../Objects/call.c:283
#14 _PyFunction_FastCallKeywords (func=<optimized out>, stack=<optimized out>, nargs=<optimized out>, kwnames=<optimized out>) at ../Objects/call.c:408
#15 0x000000000054e5ac in call_function (kwnames=0x0, oparg=<optimized out>, pp_stack=<synthetic pointer>) at ../Python/ceval.c:4616
#16 _PyEval_EvalFrameDefault (f=<optimized out>, throwflag=<optimized out>) at ../Python/ceval.c:3124
#17 0x00000000005d91fc in PyEval_EvalFrameEx (throwflag=0, f=Frame 0x926ee8, for file sleepLoop.py, line 4, in main ()) at ../Python/ceval.c:547
#18 function_code_fastcall (globals=<optimized out>, nargs=<optimized out>, args=<optimized out>, co=<optimized out>) at ../Objects/call.c:283
#19 _PyFunction_FastCallKeywords (func=<optimized out>, stack=<optimized out>, nargs=<optimized out>, kwnames=<optimized out>) at ../Objects/call.c:408
#20 0x000000000054e5ac in call_function (kwnames=0x0, oparg=<optimized out>, pp_stack=<synthetic pointer>) at ../Python/ceval.c:4616
#21 _PyEval_EvalFrameDefault (f=<optimized out>, throwflag=<optimized out>) at ../Python/ceval.c:3124
#22 0x000000000054bcc2 in PyEval_EvalFrameEx (throwflag=0, f=Frame 0x7ffff78739f8, for file sleepLoop.py, line 14, in <module> ())
at ../Python/ceval.c:547
#23 _PyEval_EvalCodeWithName (_co=<optimized out>, globals=<optimized out>, locals=<optimized out>, args=<optimized out>, argcount=<optimized out>,
kwnames=0x0, kwargs=0x0, kwcount=<optimized out>, kwstep=2, defs=0x0, defcount=0, kwdefs=0x0, closure=0x0, name=0x0, qualname=0x0)
at ../Python/ceval.c:3930
#24 0x000000000054e0a3 in PyEval_EvalCodeEx (closure=0x0, kwdefs=0x0, defcount=0, defs=0x0, kwcount=0, kws=0x0, argcount=0, args=0x0,
locals=<optimized out>, globals=<optimized out>, _co=<optimized out>) at ../Python/ceval.c:3959
#25 PyEval_EvalCode (co=<optimized out>, globals=<optimized out>, locals=<optimized out>) at ../Python/ceval.c:524
#26 0x0000000000630ce2 in run_mod (mod=<optimized out>, filename=<optimized out>,
globals={'__name__': '__main__', '__doc__': None, '__package__': None, '__loader__': <SourceFileLoader(name='__main__', path='sleepLoop.py') at remote 0x7ffff7805f60>, '__spec__': None, '__annotations__': {}, '__builtins__': <module at remote 0x7ffff78cac28>, '__file__': 'sleepLoop.py', '__cached__': None, 'time': <module at remote 0x7ffff77d5c28>, 'main': <function at remote 0x7ffff78411e0>, 'foo': <function at remote 0x7ffff7731c80>, 'bar': <function at remote 0x7ffff7731d08>},
locals={'__name__': '__main__', '__doc__': None, '__package__': None, '__loader__': <SourceFileLoader(name='__main__', path='sleepLoop.py') at remote 0x7ffff7805f60>, '__spec__': None, '__annotations__': {}, '__builtins__': <module at remote 0x7ffff78cac28>, '__file__': 'sleepLoop.py', '__cached__': None, 'time': <module at remote 0x7ffff77d5c28>, 'main': <function at remote 0x7ffff78411e0>, 'foo': <function at remote 0x7ffff7731c80>, 'bar': <function at remote 0x7ffff7731d08>}, flags=<optimized out>, arena=<optimized out>) at ../Python/pythonrun.c:1035
#27 0x0000000000630d97 in PyRun_FileExFlags (fp=0x92e490, filename_str=<optimized out>, start=<optimized out>,
globals={'__name__': '__main__', '__doc__': None, '__package__': None, '__loader__': <SourceFileLoader(name='__main__', path='sleepLoop.py') at remote 0x7ffff7805f60>, '__spec__': None, '__annotations__': {}, '__builtins__': <module at remote 0x7ffff78cac28>, '__file__': 'sleepLoop.py', '__cached__': No--Type <RET> for more, q to quit, c to continue without paging--
ne, 'time': <module at remote 0x7ffff77d5c28>, 'main': <function at remote 0x7ffff78411e0>, 'foo': <function at remote 0x7ffff7731c80>, 'bar': <function at remote 0x7ffff7731d08>},
locals={'__name__': '__main__', '__doc__': None, '__package__': None, '__loader__': <SourceFileLoader(name='__main__', path='sleepLoop.py') at remote 0x7ffff7805f60>, '__spec__': None, '__annotations__': {}, '__builtins__': <module at remote 0x7ffff78cac28>, '__file__': 'sleepLoop.py', '__cached__': None, 'time': <module at remote 0x7ffff77d5c28>, 'main': <function at remote 0x7ffff78411e0>, 'foo': <function at remote 0x7ffff7731c80>, 'bar': <function at remote 0x7ffff7731d08>}, closeit=1, flags=0x7fffffffe2ac) at ../Python/pythonrun.c:988
#28 0x00000000006319ff in PyRun_SimpleFileExFlags (fp=0x92e490, filename=<optimized out>, closeit=1, flags=0x7fffffffe2ac) at ../Python/pythonrun.c:429
#29 0x000000000065432e in pymain_run_file (p_cf=0x7fffffffe2ac, filename=<optimized out>, fp=0x92e490) at ../Modules/main.c:427
#30 pymain_run_filename (cf=0x7fffffffe2ac, pymain=0x7fffffffe380) at ../Modules/main.c:1627
#31 pymain_run_python (pymain=0x7fffffffe380) at ../Modules/main.c:2877
#32 pymain_main (pymain=<optimized out>, pymain=<optimized out>) at ../Modules/main.c:3038
#33 0x000000000065468e in _Py_UnixMain (argc=<optimized out>, argv=<optimized out>) at ../Modules/main.c:3073
#34 0x00007ffff7be209b in __libc_start_main (main=0x4bc560 <main>, argc=2, argv=0x7fffffffe4c8, init=<optimized out>, fini=<optimized out>,
rtld_fini=<optimized out>, stack_end=0x7fffffffe4b8) at ../csu/libc-start.c:308
#35 0x00000000005e0e8a in _start () at ../Modules/main.c:797