When I recently want to use TitanHide
a tool to hide the debugger I learned that for years in X64 windows there's something called Kernel Patch Protection
Microsoft put it there to keep you off messing with ya drivers in some internals like IDT, GDT and stuff.
However read the Wikipedia article - it's not really a protection. And what I've see so far about the KPP is it's nasty BSOD.
So it's in the end that KPP is just bug. Debug it & fix it.
@ Jason I guess the KPP
is probably something that stands there in between you and the beloved PH Terminators feature.
And yesss there is cure:
KPP Destroyer (including source code) - 2015
Test it on my Win7Sp1 X64 and it works fine.
p.s. Later on I noticed that I don't really need kernel mode TitanHide thing since the plugin 'scylla hide' really worked well to get the debugger into some vmprotected targets.