flat assembler
Message board for the users of flat assembler.

Index > OS Construction > Switching from long mode to compability mode.

Author
Thread Post new topic Reply to topic
Mac2004



Joined: 15 Dec 2003
Posts: 313
Mac2004
Hi!

AMD64 manual says that switching from long mode to compability mode requirea changing Long mode bit to zero from CS register.

Here's my question: How this changing can be done? The long mode does not allow selector:offset jumps. and as far as I know changing CS register usually needs some tricks to do. Direct writing is not allowed.

regards,
Mac2004
Post 22 Jun 2007, 06:27
View user's profile Send private message Reply with quote
f0dder



Joined: 19 Feb 2004
Posts: 3170
Location: Denmark
f0dder
a couple of pushes and iretd?
Post 22 Jun 2007, 11:30
View user's profile Send private message Visit poster's website Reply with quote
Mac2004



Joined: 15 Dec 2003
Posts: 313
Mac2004
f0dder: Thanx for the idea. Smile I have to test it.

regards,
Mac2004
Post 22 Jun 2007, 13:11
View user's profile Send private message Reply with quote
Display posts from previous:
Post new topic Reply to topic

Jump to:  


< Last Thread | Next Thread >
Forum Rules:
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum


Copyright © 1999-2020, Tomasz Grysztar.

Powered by rwasa.