Re: [XEN PATCH v3 5/6] x86/MCE: add default switch case in init_nonfatal_mce_checker()

[Sergiy Kibrik <sergiy_kibrik@xxxxxxxx>]

16.05.24 12:46, Jan Beulich:
> > > --- a/xen/arch/x86/cpu/mcheck/non-fatal.c
> > > +++ b/xen/arch/x86/cpu/mcheck/non-fatal.c
> > > @@ -29,9 +29,13 @@ static int __init cf_check init_nonfatal_mce_checker(void)
> > >                 /* Assume we are on K8 or newer AMD or Hygon CPU here */
> > >                 amd_nonfatal_mcheck_init(c);
> > >                 break;
> > > +
> > >         case X86_VENDOR_INTEL:
> > >                 intel_nonfatal_mcheck_init(c);
> > >                 break;
> > > +
> > > +       default:
> > > +               return -ENODEV;
> > >         }
> > >         printk(KERN_INFO "mcheck_poll: Machine check polling timer started.\n");
> > >         return 0;
> > ... converting this to an error return still isn't justified. On one hand it's
> > benign because we still don't check return values from initcalls. Yet otoh it
> > isn't really an error, is it?
> I realize earlier in the function there are error returns, too. I question at
> least the former of them as well. And the latter shouldn't be an error at least
> when the vendor isn't going to be handled in the switch().
I'll just return 0 then, and maybe leave a comment, as this code will 
start to look a bit unnatural to me.
  -Sergiy