Re: [PATCH v4 05/10] hyper-v: use fast hypercall for HVCALL_SIGNAL_EVENT

Andy Shevchenko
2017-05-27T17:58:45Z

On Wed, May 24, 2017 at 3:04 PM, Vitaly Kuznetsov <vkuznets@redhat.com> wrote:
> We need to pass only 8 bytes of input for HvSignalEvent which makes it a
> perfect fit for fast hypercall. hv_input_signal_event_buffer is not needed
> any more and hv_input_signal_event is converted to union for convenience.

> +union hv_input_signal_event {

Union aliasing is UB. Avoid it for good.

> + u64 as_uint64;
> + struct {
> + union hv_connection_id connectionid;
> + u16 flag_number;
> + u16 rsvdz;
> + };
> };

--
With Best Regards,
Andy Shevchenko