Re: [PATCH] xen/arm: Restricted access to IFSR32_EL2 and FPEXC32_EL2

[Julien Grall <julien.grall@linaro.org>]

Hi Vijaya,

On 05/27/2014 11:37 AM, vijay.kilari@gmail.com wrote:
> From: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
> 
> Some platforms does not support aarch32 mode. So access only if
> platform supports it. Accessing these registers will
> raise exception
> 
> Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
> ---
>  xen/arch/arm/arm64/vfp.c |    6 ++++--
>  xen/arch/arm/traps.c     |    7 +++++--
>  2 files changed, 9 insertions(+), 4 deletions(-)
> 
> diff --git a/xen/arch/arm/arm64/vfp.c b/xen/arch/arm/arm64/vfp.c
> index 3cd2b1b..c550a68 100644
> --- a/xen/arch/arm/arm64/vfp.c
> +++ b/xen/arch/arm/arm64/vfp.c
> @@ -28,7 +28,8 @@ void vfp_save_state(struct vcpu *v)
>  
>      v->arch.vfp.fpsr = READ_SYSREG32(FPSR);
>      v->arch.vfp.fpcr = READ_SYSREG32(FPCR);
> -    v->arch.vfp.fpexc32_el2 = READ_SYSREG32(FPEXC32_EL2);
> +    if ( cpu_has_el2_32 )

You should use is_32bit_domain here. If your platform doesn't support
aarch32 mode, then we should not create 32bit domain.

I think you will have to deny somewhere the domain creation in this case.

Regards,

-- 
Julien Grall