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

[Alessandro Zucchelli <alessandro.zucchelli@xxxxxxxxxxx>]

On 2024-06-26 03:13, Stefano Stabellini wrote:

Hi,
> 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
Yes, this macro will be deviated, you may ignore this patch.

> 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;
--
Alessandro Zucchelli, B.Sc.

Software Engineer, BUGSENG (https://bugseng.com)