Re: [git-pull -tip V2] x86: cpu architecture debug code

[Jaswinder Singh Rajput <jaswinder@kernel.org>]

On Wed, 2009-03-11 at 11:53 +0100, Ingo Molnar wrote:
> * Jaswinder Singh Rajput <jaswinder@kernel.org> wrote:
> 
> > On Tue, 2009-03-10 at 18:45 +0100, Ingo Molnar wrote:
> > > Thanks - picked it up into tip:x86/debug. (Note that i 
> > > rearranged the Makefile details a bit so that it does not 
> > > conflict with tip:perfcounters)
> > > 
> > > Not yet in tip:master, because it triggers this build failure:
> > > 
> > > arch/x86/kernel/cpu/cpu_debug.c: In function ‘print_dt’:
> > > arch/x86/kernel/cpu/cpu_debug.c:475: error: implicit declaration of function ‘store_ldt’
> > > 
> > 
> > Here is the fix.
> > 
> > The following changes since commit 259ef6fcea4046fe24495b1e3631c1b905c531c1:
> >   Jaswinder Singh Rajput (1):
> >         x86: cpu architecture debug code
> > 
> > are available in the git repository at:
> > 
> >   git://git.kernel.org/pub/scm/linux/kernel/git/jaswinder/linux-2.6-tip-cpu.git master
> > 
> > Jaswinder Singh Rajput (1):
> >       x86: cpu_debug.c remove some dependency
> > 
> >  arch/x86/kernel/cpu/cpu_debug.c |    8 ++++----
> >  1 files changed, 4 insertions(+), 4 deletions(-)
> > 
> > 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,

> >  	print_desc_ptr("IDT", seq, dt);
> >  
> >  	/* GDT */
> > -	store_gdt((struct desc_ptr *)&dt);
> > +	native_store_gdt((struct desc_ptr *)&dt);
> >  	print_desc_ptr("GDT", seq, dt);
> >  
> >  	/* LDT */
> > -	store_ldt(ldt);
> > +	asm volatile("sldt %0" : "=m" (ldt));
> >  	seq_printf(seq, " LDT\t: %016lx\n", ldt);
> >  
> >  	/* TR */
> > -	store_tr(ldt);
> > +	asm volatile("str %0" : "=r" (ldt));
> >  	seq_printf(seq, " TR\t: %016lx\n", ldt);
> 
> we do have a store_tr() primitive - why open code the assembly?
> 

It is a single line code to avoid further conflicts, so i moved it here.

Can you please test are these works on your boxes.

Thanks,

--
JSR