Re: [Qemu-arm] [Qemu-devel] [PATCH 08/11] target-arm: Forbid mode switch to Mon from Secure EL1

[Sergey Fedorov]

On 15.02.2016 20:22, Peter Maydell wrote:
> In v8 trying to switch mode to Mon from Secure EL1 is an
> illegal mode switch. (In v7 this is impossible as all secure
> modes except User are at EL3.) We can handle this case by
> making a switch to Mon valid only if the current EL is 3,
> which then gives the correct answer whether EL3 is AArch32
> or AArch64.
>
> Signed-off-by: Peter Maydell <address@hidden>

Reviewed-by: Sergey Fedorov <address@hidden>

> ---
>  target-arm/helper.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/target-arm/helper.c b/target-arm/helper.c
> index 4074b97..e7b3eb3 100644
> --- a/target-arm/helper.c
> +++ b/target-arm/helper.c
> @@ -5188,7 +5188,7 @@ static int bad_mode_switch(CPUARMState *env, int mode)
>          return !arm_feature(env, ARM_FEATURE_EL2)
>              || arm_current_el(env) < 2 || arm_is_secure(env);
>      case ARM_CPU_MODE_MON:
> -        return !arm_is_secure(env);
> +        return arm_current_el(env) < 3;
>      default:
>          return 1;
>      }