Re: [RESEND][PATCH v2 5/7] xen: include xen/guest_access.h rather than asm/guest_access.h

[Julien Grall <julien@xxxxxxx>]

On 18/08/2020 17:04, Jan Beulich wrote:
> On 18.08.2020 15:14, Julien Grall wrote:
> > On 18/08/2020 12:32, Jan Beulich wrote:
> > > On 18.08.2020 10:58, Julien Grall wrote:
> > > > > One option. Personally I'd prefer to avoid introduction of yet another
> > > > > constant, by leveraging __XEN_GUEST_ACCESS_H__ instead.
> > > > I thought about it but it doesn't prevent new inclusions of asm/guest_access.h. 
> > > > For instance, the following would still compile:
> > > >
> > > > #include <xen/guest_access.h>
> > > >
> > > > [...]
> > > >
> > > > #include <asm/guest_access.h>
> > > But where's the problem with this? The first #include will already
> > > have resulted in the inclusion of asm/guest_access.h, so the second
> > > #include is simply a no-op.
> > A couple of reasons:
> >     1) I don't consider this solving completely your original request [1]
> >     2) I don't see how this is more important to prevent including 
> > <asm/guest_access.h> before and not after. Both will still compile fine, we just want to 
> > avoid it.
> >
> >
> > [1] "Is there any chance you could take measures to avoid new inclusions of 
> > asm/guest_access.h to appear?"
> Is
>
> #include <xen/guest_access.h>
> [...]
> #include <asm/guest_access.h>
>
> actually a problem (as opposed to an asm/ include without any include
> of the xen/ one at all)?
Neither of them are really a problem today. So it is not entirely clear 
why we would want to prevent one and not the other.
Cheers,

--
Julien Grall