Re: [patch, 2.6.10-rc3] safe_hlt() & NMIs

[Maciej W. Rozycki]

On Thu, 16 Dec 2004, Ingo Molnar wrote:

> c0125ee9:     1529 	fa                   	cli    
>                  ^---------------------------------- # of profiler hits
> c0125eea:      507 	fb                   	sti    
> c0125eeb:        0 	fa                   	cli    
> c0125eec:     3719 	fb                   	sti    
> c0125eed:        0 	fa                   	cli    
> c0125eee:     1579 	fb                   	sti    
> c0125eef:        0 	fa                   	cli    
> c0125ef0:     3317 	fb                   	sti    
> c0125ef1:        0 	fa                   	cli    
> c0125ef2:     3030 	fb                   	sti    
> c0125ef3:        0 	fa                   	cli    
> c0125ef4:     2497 	fa                   	cli    
> c0125ef5:     1055 	fb                   	sti    
> c0125ef6:        0 	fa                   	cli    
[...]
> the 'cli' is always a 'black hole' to the NMI, while the second of two
> consecutive cli's are not.

 It looks like the 'sti' is actually the black hole -- remember interrupts
are traps, that is they are probed for and taken after instruction
execution.

  Maciej
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