Re: [PATCH] Re: SSE related security hole

[Brian Gerst]

Linus Torvalds wrote:
> 
> On Fri, 19 Apr 2002, H. Peter Anvin wrote:
> 
>>Indeed.  Logically, FNINIT should have been extended to initialize it all -
>>- it is a security hole that it doesn't initialize MMX properly.
> 
> 
> Well, MMX should arguably be initialized with "emms", so the proper
> sequence migth be something like
> 
> 	if (sse)
> 		asm("emms");
> 	asm("fninit");
> 
> What does emms do to SSE2?
> 
> 		Linus
> 

All emms does is reset the tag word.  It doesn't touch the registers.

-- 

						Brian Gerst