On windows 10 I have a Oracle VM VirtualBox running with Ubuntu 20.04.5 and sometimes an application (started with sudo) just "hangs". I am not able to kill the job using
kill -9 <process_id>
because this kill process will also hang.
Is there any other way to stop such a process without force-stopping the VM?
Output from ps -ef:
root 3207 3166 0 10:26 pts/1 00:00:00 sudo ./isp_cli 79 sjb50_bootloader_secondary_v0.1.0m_kja
root 3208 3207 0 10:26 pts/1 00:00:00 ./isp_cli 79 sjb50_bootloader_secondary_v0.1.0m_kjar_190
The command ps -Al shows
4 S 0 1811 1714 0 80 0 - 5142 - pts/0 00:00:00 sudo
4 D 0 1812 1811 0 80 0 - 1634 - pts/0 00:00:00 isp_cli
It is an application to communicate via USB <-> CAN with some hardware device. And for some testing (interrupting some communication process) it will always fail running a second time. And it becomes quite cumbersome to restart the VM in each of these cases.
I also tried to use
sudo pkill -9 -f isp_cli
sudo killall -9 isp_cli
sudo kill -hup 1811
sudo kill -15 1811
but these commands also were unable to stop the actual blocking process .., and hang as well.
I further tried to get some more information about the process, but even if I try
sudo cat /proc/1916/stack
this also hangs. No output, no return to the terminal. Just nothing!