Re: [Qemu-arm] [PATCH 6/6] armv7m: Clear FAULTMASK on return from non-NMI exceptions

["Alex Bennée" <alex.bennee@linaro.org>]

Peter Maydell <peter.maydell@linaro.org> writes:

> From: Michael Davidsaver <mdavidsaver@gmail.com>
>
> FAULTMASK must be cleared on return from all
> exceptions other than NMI.
>
> Signed-off-by: Michael Davidsaver <mdavidsaver@gmail.com>
> Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
>  target/arm/helper.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/target/arm/helper.c b/target/arm/helper.c
> index dc383d1..cfbc622 100644
> --- a/target/arm/helper.c
> +++ b/target/arm/helper.c
> @@ -5969,8 +5969,13 @@ static void do_v7m_exception_exit(CPUARMState *env)
>      uint32_t xpsr;
>
>      type = env->regs[15];
> -    if (env->v7m.exception != 0)
> +    if (env->v7m.exception != ARMV7M_EXCP_NMI) {
> +        /* Auto-clear FAULTMASK on return from other than NMI */
> +        env->daif &= ~PSTATE_F;
> +    }
> +    if (env->v7m.exception != 0) {
>          armv7m_nvic_complete_irq(env->nvic, env->v7m.exception);
> +    }
>
>      /* Switch to the target stack.  */
>      switch_v7m_sp(env, (type & 4) != 0);

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>

--
Alex Bennée