NI-SCOPE driver causes segmentation fault with python module

[Petazz]

Hi,

Not sure if this is the right location but I have a weird issue using the python module niscope.

With a very simple example code here the driver seems to crash.

debug_ni.py:

import niscope

resource_name = 'PXI1Slot2'

asd = niscope.Session(resource_name=resource_name, id_query=True, reset_device=True)

And the execution

$ python debug_ni.py
Segmentation fault (core dumped)

It seems to segfault on exit.

I tried running it through gdb to try to underpin the issue. The execution is below

$ gdb python
GNU gdb (Ubuntu 12.1-0ubuntu1~22.04) 12.1
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For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from python...
(No debugging symbols found in python)
(gdb) run debug_ni.py
Starting program: /home/amri/.local/share/virtualenvs/nitest-H47v5LJV/bin/python debug_ni.py
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/usr/lib/x86_64-linux-gnu/libthread_db.so.1".
[Detaching after vfork from child process 5344]
[Detaching after vfork from child process 5345]
[Detaching after vfork from child process 5346]
[New Thread 0x7ffff09ff640 (LWP 5347)]
[New Thread 0x7ffff01fe640 (LWP 5348)]
[New Thread 0x7ffff6c7e640 (LWP 5351)]
[New Thread 0x7ffff6c6c640 (LWP 5352)]
[New Thread 0x7ffff6269640 (LWP 5353)]
[New Thread 0x7fffd27ff640 (LWP 5362)]
[New Thread 0x7fffd1ffe640 (LWP 5363)]
[New Thread 0x7fffd17fd640 (LWP 5364)]
[New Thread 0x7fffd0ffc640 (LWP 5365)]
[New Thread 0x7fffc3fff640 (LWP 5369)]
[New Thread 0x7fffc37fe640 (LWP 5370)]
[New Thread 0x7fffc2ffd640 (LWP 5371)]
[New Thread 0x7fffc27fc640 (LWP 5372)]
[New Thread 0x7fffc1ffb640 (LWP 5376)]
[New Thread 0x7fffc17fa640 (LWP 5377)]
[New Thread 0x7fffc0ff9640 (LWP 5378)]
[New Thread 0x7fffabfff640 (LWP 5379)]
[New Thread 0x7fffab7fe640 (LWP 5380)]
[New Thread 0x7fffaaffd640 (LWP 5381)]
[New Thread 0x7fffaa7fc640 (LWP 5382)]
[New Thread 0x7fffa9ffb640 (LWP 5383)]
[New Thread 0x7fffa97fa640 (LWP 5384)]
[New Thread 0x7fffa8ff9640 (LWP 5385)]
[New Thread 0x7fff87fff640 (LWP 5389)]
[New Thread 0x7fff877fe640 (LWP 5390)]
[New Thread 0x7fff86ffd640 (LWP 5391)]
[New Thread 0x7fff867fc640 (LWP 5392)]
[New Thread 0x7fff84fff640 (LWP 5393)]
[Thread 0x7fff84fff640 (LWP 5393) exited]
[Detaching after vfork from child process 5394]
[New Thread 0x7fff84fff640 (LWP 5396)]
[Thread 0x7fff84fff640 (LWP 5396) exited]
[New Thread 0x7ffff5ec1640 (LWP 5400)]
[Detaching after vfork from child process 5419]
[Detaching after vfork from child process 5420]
[Detaching after vfork from child process 5423]
[Thread 0x7ffff6c7e640 (LWP 5351) exited]
[Thread 0x7ffff6c6c640 (LWP 5352) exited]
[Thread 0x7fffd27ff640 (LWP 5362) exited]

Thread 1 "python" received signal SIGSEGV, Segmentation fault.
0x0000555556040031 in ?? ()
(gdb) bt
#0 0x0000555556040031 in ?? ()
#1 0x00007fff8500f345 in ?? () from /opt/ni-ceip/niceipcore.so
#2 0x00007fff8500f3a9 in UDCCoreIsEnabled () from /opt/ni-ceip/niceipcore.so
#3 0x00007ffff69845d6 in ?? () from /usr/lib/x86_64-linux-gnu/libniscope.so.1
#4 0x00007ffff698b699 in ?? () from /usr/lib/x86_64-linux-gnu/libniscope.so.1
#5 0x00007ffff6981c0a in ?? () from /usr/lib/x86_64-linux-gnu/libniscope.so.1
#6 0x00007ffff6981cb5 in ?? () from /usr/lib/x86_64-linux-gnu/libniscope.so.1
#7 0x00007ffff6981d49 in ?? () from /usr/lib/x86_64-linux-gnu/libniscope.so.1
#8 0x00007ffff6921f95 in ?? () from /usr/lib/x86_64-linux-gnu/libniscope.so.1
#9 0x00007ffff6921ff9 in ?? () from /usr/lib/x86_64-linux-gnu/libniscope.so.1
#10 0x00007ffff6920a93 in ?? () from /usr/lib/x86_64-linux-gnu/libniscope.so.1
#11 0x00007ffff683d821 in ?? () from /usr/lib/x86_64-linux-gnu/libniscope.so.1
#12 0x00007ffff7c45495 in __run_exit_handlers (status=0, listp=0x7ffff7e1a838 <__exit_funcs>, run_list_atexit=run_list_atexit@entry=true,
run_dtors=run_dtors@entry=true) at ./stdlib/exit.c:113
#13 0x00007ffff7c45610 in __GI_exit (status=<optimized out>) at ./stdlib/exit.c:143
#14 0x00007ffff7c29d97 in __libc_start_call_main (main=main@entry=0x55555577bff0, argc=argc@entry=2, argv=argv@entry=0x7fffffffde48)
at ../sysdeps/nptl/libc_start_call_main.h:74
#15 0x00007ffff7c29e40 in __libc_start_main_impl (main=0x55555577bff0, argc=2, argv=0x7fffffffde48, init=<optimized out>,
fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fffffffde38) at ../csu/libc-start.c:392
#16 0x000055555577bf25 in _start ()

This is not a critical issue as the driver works but just very annoying that it crashes on teardown.

What could be causing the issue?

ni-scope installed on Ubuntu is of version 23.8.0.49304-0+f152

Current kernel is

$ cat /proc/version_signature
Ubuntu 6.5.0-21.21~22.04.1-generic 6.5.8

[ChambersC]

Hello,

We think that this is similar to a public bug that we have for NI-SCOPE.

That bug is at the bottom of the list on this page:
https://www.ni.com/en/support/documentation/bugs/23/linux-device-drivers-2023-q4-known-issues.html

Text from that page is:

On Linux, some driver function calls may generate a spurious SIGALRM, which may interrupt certain operations (e.g. fetching measurements). For example, niDCPower_FetchMultiple() may return error -1074097127.

Known impacted drivers: NI-DCPower, NI-SCOPE.

Workaround:

If you run into this issue and wish to disable it, copy the attached file for the appropriate driver from the Downloads section to

/var/local/natinst/systemsettings/

If this doesn't fix this issue, please let me know and we can do some further investigations into this.

Thanks!

[kirsch]

Please also close your session before exit, and if you still see the crash, then add a 1-2 seconds wait. The theory is that there are threads running on exit that aren't being cleaned up right.

[Petazz]

Hi,

I tried that with the following code but it still segfaults (note, this is not the same fault that was mentioned earlier).

debug_ni.py:

import niscope
import time

resource_name = 'PXI1Slot2'

asd = niscope.Session(resource_name=resource_name, id_query=False, reset_device=False)
del asd
time.sleep(3)

$ python debug_ni.py
Segmentation fault (core dumped)

[Petazz]

---

Workaround:

If you run into this issue and wish to disable it, copy the attached file for the appropriate driver from the Downloads section to

---

Where can I find the file attachment?

[ChambersC]

Ah, yeah. That is confusing. The attachments are at the very bottom of that page. This is the link to it

NI Scope File