Quick reply...
dmesg doesn't have long enough logs. After reboot I cannot see the SGX errors in the log. The oldest lines are about the last reboot. Booting process writes so much lines in dmesg.

I'm going to put dmesg logging into the script.

Does dmesg >> output.txt overwrite output.txt or add new lines to it?

And how can I filter out lines containing "slide" or "kb_lock"?