The reason your "dyndbg=module e1000" does not work is because dyndbg=... is only processed at boot time and therefore only affects *built-in* modules. e1000 is a dynamically loaded module not a built-in.
What you need is the module.dyndbg=... form as in: "e1000.dyndbg=+p" See especially line 259, 291 of: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation /admin-guide/dynamic-debug-howto.rst -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1838070 Title: Unable to add dyndbg to command line To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1838070/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs