Page 1 of 1
whats so bad about a ring3 stack
Posted: Fri Mar 31, 2006 8:11 pm
by earlz
Well i was thinking about me being told "you need a tss entry to tell where the kernel stack is" but really cant i use the user stack then do a "software stack switch"
Re:whats so bad about a ring3 stack
Posted: Fri Mar 31, 2006 8:19 pm
by Colonel Kernel
Ask yourself this question: "What does the CPU do when an interrupt occurs while it's running in ring 3?"
If you don't know the answer, consult the Intel manuals.
Re:whats so bad about a ring3 stack
Posted: Fri Mar 31, 2006 10:34 pm
by earlz
irc it push's cs,eip,ss,esp(not in that order of course) and loads cs and eip from idt
I'm not talking about ints but rather irq's really but still I dont see any problem with that
Re:whats so bad about a ring3 stack
Posted: Sat Apr 01, 2006 2:03 am
by Colonel Kernel
Ask yourself this question: Why would the CPU bother pushing ss and esp if it wasn't planning to switch stacks...?
Also, what you call "irqs" and what I call "interrupts" are the same thing.
Re:whats so bad about a ring3 stack
Posted: Sat Apr 01, 2006 3:31 pm
by earlz
yea gues you got a point there
and so im on my way to get a tss ;D