Re: [PATCH v3] tty: vt: keyboard: add default switch-case, to handle smatch-warnings in method vt_do_kdgkb_ioctl

[Pavel Skripkin]

On 11/7/21 01:17, Ajay Garg wrote:
> On Sun, Nov 7, 2021 at 3:42 AM Pavel Skripkin <paskripkin@xxxxxxxxx> wrote:
> > On 11/7/21 01:03, Ajay Garg wrote:
> > > diff --git a/drivers/tty/vt/keyboard.c b/drivers/tty/vt/keyboard.c
> > > index c7fbbcdcc346..b83e7669658d 100644
> > > --- a/drivers/tty/vt/keyboard.c
> > > +++ b/drivers/tty/vt/keyboard.c
> > > @@ -2090,6 +2090,12 @@ int vt_do_kdgkb_ioctl(int cmd, struct kbsentry __user *user_kdgkb, int perm)
> > >
> > >               ret = 0;
> > >               break;
> > > +     default: {
> > > +             kbs = NULL;
> > > +             ret = -ENOIOCTLCMD;
> > > +
> > > +             break;
> > > +     }
> >
> > Are these brackets needed here? There are no local variables inside
> > default case.
>
> Hmm,
>
> * case KDGKBSENT: uses braces.
> * case KDSKBSENT: does not use braces.
>
> I based the layout for default-case on the same lines as case
> KDGKBSENT: , as I prefer explicit braces :)

I am not against these braces, but I, honestly, dislike them, because 
`case : {` syntax looks ugly _to me_.

KDGKBSENT uses it because of local variable `len` and not using them 
will cause build error.

I didn't find any strict requirements to not use brackets when there is 
no local variable, so it's up to maintainers (again).


Anyway, thank for respinning :)



With regards,
Pavel Skripkin