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

[Andrey Ryabinin <a.ryabinin@samsung.com>]

On 12/13/2014 11:51 PM, Manfred Spraul wrote:
> Hi,
> 
> On 12/04/2014 12:25 AM, Andrew Morton wrote:
>> On Wed, 03 Dec 2014 15:41:21 +0300 Andrey Ryabinin <a.ryabinin@samsung.com> 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@google.com>
>>> Fixes: ed4d4902ebdd ("mm, hugetlb: remove hugetlb_zero and hugetlb_infinity")
>>> Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
>>> ---
>>>   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.
> 

Agreed, I think this should work.

> -- 
>     Manfred
> 
> 
>