Re: [Xen-devel] [PATCH V7] vm_event: Allow subscribing to write events for specific MSR-s

["Jan Beulich" <jbeulich@xxxxxxxx>]

>>> Razvan Cojocaru <rcojocaru@xxxxxxxxxxxxxxx> 05/05/16 12:51 PM >>>
>On 05/04/2016 05:45 PM, Jan Beulich wrote:
>>> +        *msr &= 0x1fff;
>>> > +        return &d->arch.monitor_msr_bitmap->high;
>>> > +
>>> > +    default:
>>> > +        return NULL;
>>> > +    }
>>> > +}
>>> > +
>>> > +static int monitor_enable_msr(struct domain *d, u32 msr)
>>> > +{
>>> > +    u32 *bitmap;
>> Together with the above - unsigned long * please (and the helper
>> function's return type should then also be unsigned long *).
>
>But returning unsigned long * from the helper function would require
>three aditional casts (when returning
>&d->arch.monitor_msr_bitmap->{low,hypervisor,high}), otherwise the
>compiler will complain about incompatible pointer types.

Well, I also suggested to make those arrays actual bitmaps. The way it is
now the fact that you use void * as return type means you hide a cast from
u8(*)[1024] to u32*. Using proper bitmaps and a proper return type will avoid
all that.

Jan


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel