L4 Driver Security

Hey List,

me again with one (hopefully final) question.

I'm learning about Driver Security in L4Re. I have some statements
which I would like to have confirmed to understand the underlying
principles:

1. L4 Drivers use DMA and are therefore able to write directly to the
device memory and thus can cause crashes or damage if not carefully
implemented.
2. While the L4Re Io-Server manages the access of drivers to the
hardware's address spaces, it doesn't prevent drivers to write "bad"
things into the device memory.
3. Untrusted, untested drivers can cause system crashes.

best regards

Tobi