[PATCH v2 2/7] ARM: virt: allow the kernel to be entered in HYP mode

[tony@atomide.com (Tony Lindgren)]

* Nicolas Pitre <nicolas.pitre@linaro.org> [121006 07:07]:
> On Sat, 6 Oct 2012, Marc Zyngier wrote:
> > 
> > If so, that indicates some side effect of the safe_svcmode_maskall macro,
> > and I suspect the "movs pc, lr" bit.
> 
> That would be surprizing if the "movs pc, lr" was to blame.  This should 
> work on all architectures.
> 
> However the A bit might be to blame.
> 
> > Can you try the attached patch? It basically falls back to the previous
> > behaviour if not entered in HYP mode.
> 
> This is likely to work of course.  However I think we should try to 
> pinpoint the exact problem i.e. whether it is the A bit or the "movs pc, 
> lr" which makes a difference (it is unlikely to be both).
> 
> So I was about to suggest to test this patch as well:

No luck with this patch alone.

Regards,

Tony
 
> diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h
> index 683a1e6b60..118e22ee46 100644
> --- a/arch/arm/include/asm/assembler.h
> +++ b/arch/arm/include/asm/assembler.h
> @@ -254,8 +254,7 @@
>  	mov	lr , \reg
>  	and	lr , lr , #MODE_MASK
>  	cmp	lr , #HYP_MODE
> -	orr	\reg , \reg , #PSR_A_BIT | PSR_I_BIT | PSR_F_BIT
> -	bic	\reg , \reg , #MODE_MASK
> +	mov	\reg , #PSR_I_BIT | PSR_F_BIT
>  	orr	\reg , \reg , #SVC_MODE
>  THUMB(	orr	\reg , \reg , #PSR_T_BIT	)
>  	msr	spsr_cxsf, \reg
> 
> 
> Nicolas