Re: [qemu-s390x] [PATCH v2 4/7] s390x/tcg: SET CLOCK COMPARATOR can clear CKC interrupts

[Thomas Huth]

On 20.06.2018 12:08, David Hildenbrand wrote:
> Let's stop the timer and delete any pending CKC IRQ before doing
> anything else.
> 
> Signed-off-by: David Hildenbrand <address@hidden>
> ---
>  target/s390x/misc_helper.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/target/s390x/misc_helper.c b/target/s390x/misc_helper.c
> index 6ccbe1fe9a..d5f9f5e1d3 100644
> --- a/target/s390x/misc_helper.c
> +++ b/target/s390x/misc_helper.c
> @@ -158,6 +158,12 @@ void HELPER(sckc)(CPUS390XState *env, uint64_t time)
>      Error *err = NULL;
>      S390TOD tod_base;
>  
> +    /* stop the timer and remove pending CKC IRQs */
> +    timer_del(env->tod_timer);
> +    qemu_mutex_lock_iothread();
> +    env->pending_int &= ~INTERRUPT_EXT_CLOCK_COMPARATOR;
> +    qemu_mutex_unlock_iothread();

Reviewed-by: Thomas Huth <address@hidden>

>      if (time == -1ULL) {

I wonder whether that check is still adequate? Is there really a way to
disable the clock comparator like this? At least I haven't seen it in
the PoP.

>          return;
>      }
>