Re: [kvm-unit-tests PATCH v2 3/9] s390x: irq: make IRQ handler weak

David Hildenbrand
2019-11-29T12:02:00Z

On 28.11.19 13:46, Pierre Morel wrote:
> Having a weak function allows the tests programm to declare its own
> IRQ handler.
> This is helpfull for I/O tests to have the I/O IRQ handler having
> its special work to do.
>
> Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
> Reviewed-by: Thomas Huth <thuth@redhat.com>
> ---
> lib/s390x/interrupt.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/lib/s390x/interrupt.c b/lib/s390x/interrupt.c
> index 3e07867..d70fde3 100644
> --- a/lib/s390x/interrupt.c
> +++ b/lib/s390x/interrupt.c
> @@ -140,7 +140,7 @@ void handle_mcck_int(void)
> lc->mcck_old_psw.addr);
> }
>
> -void handle_io_int(void)
> +__attribute__((weak)) void handle_io_int(void)
> {
> report_abort("Unexpected io interrupt: at %#lx",
> lc->io_old_psw.addr);
>

The clear alternative would be a way to register a callback function.
That way you can modify the callback during the tests. As long as not
registered, wrong I/Os can be caught easily here. @Thomas?

--
Thanks,

David / dhildenb