Re: [PATCH 1/3] common/kernel: address violation of MISRA C Rule 13.6

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Tue, 25 Jun 2024, Jan Beulich wrote:
> On 25.06.2024 12:14, Alessandro Zucchelli wrote:
> > --- a/xen/common/kernel.c
> > +++ b/xen/common/kernel.c
> > @@ -660,14 +660,15 @@ long do_xen_version(int cmd, 
> > XEN_GUEST_HANDLE_PARAM(void) arg)
> >  
> >      case XENVER_guest_handle:
> >      {
> > +        struct domain *d = current->domain;
> 
> Can a (new) variable thus initialized please be consistently named currd?
> 
> >          xen_domain_handle_t hdl;
> >  
> >          if ( deny )
> >              memset(&hdl, 0, ARRAY_SIZE(hdl));
> >  
> > -        BUILD_BUG_ON(ARRAY_SIZE(current->domain->handle) != 
> > ARRAY_SIZE(hdl));
> > +        BUILD_BUG_ON(ARRAY_SIZE(d->handle) != ARRAY_SIZE(hdl));
> 
> Wasn't there the intention to exclude BUILD_BUG_ON() for specifically this
> (and any other similar) rule?

+1

I think if we could do that it would be ideal because those are the
difficult cases are only meant are build checks so there is no point in
applying to MISRA to them.


> > -        if ( copy_to_guest(arg, deny ? hdl : current->domain->handle,
> > +        if ( copy_to_guest(arg, deny ? hdl : d->handle,
> >                             ARRAY_SIZE(hdl) ) )
> >              return -EFAULT;
> >          return 0;
>