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Subject: Re: [git-pull -tip V2] x86: cpu architecture debug code
From: Jaswinder Singh Rajput <jaswinder@kernel.org>
To: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Ingo Molnar <mingo@elte.hu>, "H. Peter Anvin" <hpa@zytor.com>,
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Date: Fri, 13 Mar 2009 13:37:48 +0530
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On Fri, 2009-03-13 at 00:34 -0700, Jeremy Fitzhardinge wrote:
> Jaswinder Singh Rajput wrote:
> >>> Complete diff:
> >>> diff --git a/arch/x86/kernel/cpu/cpu_debug.c b/arch/x86/kernel/cpu/cpu_debug.c
> >>> index 0bdf4da..08c365a 100755
> >>> --- a/arch/x86/kernel/cpu/cpu_debug.c
> >>> +++ b/arch/x86/kernel/cpu/cpu_debug.c
> >>> @@ -464,19 +464,19 @@ static void print_dt(void *seq)
> >>>  	unsigned long ldt;
> >>>  
> >>>  	/* IDT */
> >>> -	store_idt((struct desc_ptr *)&dt);
> >>> +	native_store_idt((struct desc_ptr *)&dt);
> >>>       
> >> hm, this wont work on Xen then.
> >>
> >>     
> >
> > Strange it should work for Xen, Are you getting any error.
> >
> > Xen also uses native_store_idt:
> > arch/x86/xen/enlighten.c:	.store_idt = native_store_idt,
> >   
> 
> store_idt (and the others) are not used very much, and never in any code 
> path under Xen.  They're not really meaningful in Xen, and this code 
> will probably oops if you ran it.
> 
> I guess we could do more meaningful implementations of these ops for 
> Xen, now that there's a user.
> 

cpu_debug is availabe in -tip.

Can you test it:

[jaswinder@ht linux-2.6-tip]$ cat /sys/kernel/debug/x86/cpu/cpu*/dt/dt
 IDT	: 00000000c05617ff
 GDT	: 00000000c17040ff
 LDT	: 0000000000000000
 TR	: 0000000000000080

 IDT	: 00000000c05617ff
 GDT	: 00000000c17140ff
 LDT	: 00000000fce90000
 TR	: 0000000000000080

[jaswinder@ht linux-2.6-tip]$ 


--
JSR