Re: [PATCH] kernel: sysctl: use 'unsigned long' type for 'zero' variable

[Manfred Spraul]

This is a multi-part message in MIME format.
Hi,

On 12/04/2014 12:25 AM, Andrew Morton wrote:
> On Wed, 03 Dec 2014 15:41:21 +0300 Andrey Ryabinin <a.ryabinin@xxxxxxxxxxx> wrote:
>
> > Use the 'unsigned long' type for 'zero' variable to fix this.
> > Changing type to 'unsigned long' shouldn't affect any other users
> > of this variable.
> >
> > Reported-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
> > Fixes: ed4d4902ebdd ("mm, hugetlb: remove hugetlb_zero and hugetlb_infinity")
> > Signed-off-by: Andrey Ryabinin <a.ryabinin@xxxxxxxxxxx>
> > ---
> >   kernel/sysctl.c | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/kernel/sysctl.c b/kernel/sysctl.c
> > index 15f2511..45c45c9 100644
> > --- a/kernel/sysctl.c
> > +++ b/kernel/sysctl.c
> > @@ -120,7 +120,7 @@ static int sixty = 60;
> >   
> >   static int __maybe_unused neg_one = -1;
> >   
> > -static int zero;
> > +static unsigned long zero;

After some (useless) playing around (see the attached patch):

Using
>    .extra1=zero,
for proc_doulongvec_minmax doesn't make any sense:

 __do_proc_doulongvec_minmax() internally contains
>                       if ((min && val < *min) || (max && val > *max))
>                                 continue;

What about just deleting the offending .extra1=zero line?
.extra1=NULL has the same effect as .extra1=&zero.

--
    Manfred