Questions[deadlock](ubuntu)

I am developing a program which causes deadlocks. And I want Ubuntu to warn about all the deadlocks in the kernel, so I can know if my program succeeds. It's required that kernel can detect deadlocks automatically. And https://stackoverflow.com/questions/20892822/how-to-use-lockdep-feature-in-linux-kernel-for-deadlock-detection says that I should enable CONFIG_LOCKDEP and CONFIG_PROVE_LOCKING in .config. However, CONFIG_LOCKDEP and CONFIG_PROVE_LOCKING both depend on CONFIG_DEBUG_LOCK_ALLOC. When I enable these three options and compile, it gives me this error:

Kernel built with CONFIG_DEBUG_LOCK_ALLOC which is incompatible with the CDDL license and will prevent the module linking stage from succeeding. You must rebuild your kernel without this option enabled.

How should I solve this?

After the OS is running for a while, it may trigger for a bug that caused pkexec (including any application that use it, including synaptic) to hang. This can only be recovered from relaunching OS or gnome-shell.

This is a screenshot that describe this situation:

xhost +si:localuser:root
pkexec synaptic

I remember the same error in Manjaro with gnome 3.28, it disappeared in gnome 3.30. How do I backport the fix (if there is any) to Ubuntu 18.04?

UPDATE 1

these are my desktop environment:

$ export | grep XDG_SESS
declare -x XDG_SESSION_DESKTOP="ubuntu"
declare -x XDG_SESSION_ID="1"
declare -x XDG_SESSION_TYPE="x11"

... and synaptics version

$ apt-cache policy synaptic
synaptic:
  Installed: 0.84.3ubuntu1
  Candidate: 0.84.3ubuntu1
  Version table:
 *** 0.84.3ubuntu1 500
        500 http://archive.ubuntu.com/ubuntu bionic/universe amd64 Packages
        100 /var/lib/dpkg/status
peng@peng-ThinkPad-P51s:~$ 

UPDATE 2: it appears that it is caused by an unknown bug in gnome authentication agent, as I switched to XFCE and this problem never happens again, so now the problem becomes: how to get rid of the gnome authentication agent?

I know that when a package is being installed, the root directory [I think?] gets an administrator lock and can't make an other installation at the same time.

Is there a way to stop that installation? If it is so, is it good to do?

I heard that it is better to leave the package to get installed and then try removing it. Is that true?

I was downloading a package using the terminal. I actually wanted to install package 'A'. But, by mistake started installing package 'B'. I wanted to stop downloading 'B' and start downloading 'A'.

I wasn't able to do that. I reset my network connection. I could stop downloading the package B. But, the administrator directory was locked and wasn't able to download other packages which made me to restart my system.

What command should I use to abort the active download of packages in ubuntu?