LWN.net Logo

Qubes beta 1 released

Qubes beta 1 released

Posted Apr 14, 2011 10:25 UTC (Thu) by PaXTeam (subscriber, #24616)
In reply to: Qubes beta 1 released by jarrett.miller
Parent article: Qubes beta 1 released

> But TXT requires virtualization to do its thing.

where did you read that? 315168.pdf says this:

> Intel TXT can be used to launch any type of code. However, this section
> describes the launch, operation and teardown of a Virtual Machine
> Monitor (VMM) using Intel TXT; any other code would have a similar
> sequence.


(Log in to post comments)

Qubes beta 1 released

Posted Apr 14, 2011 10:51 UTC (Thu) by jarrett.miller (guest, #60765) [Link]

Excuse me for not being supper precise. I should have said the most common use case for TXT requires virtualization.

You are correct. Any conforming code that is able to be launched in a measured launch environment can run in TXT context. However I have yet to see a good example of when this is useful outside of virtualization. Mainly because setting up a TXT context is so expensive. After all its basically a platform reset so you have to stop all CPU's and flush all caches.

I have seen people try to do this but it just seems to have little merit in my opinion. For example Dr. Mike Reiter of UNC Chapel Hill tried to do just that for password encryption. Basically launching a TXT application for every key press (google him for the papers). But the costs seems way to high to me.

Cheers

Copyright © 2013, Eklektix, Inc.
Comments and public postings are copyrighted by their creators.
Linux is a registered trademark of Linus Torvalds