Re: + sysctl-add-proc_dointvec_unsigned-handler.patch added to -mm tree

[Alexey Dobriyan <adobriyan@gmail.com>]

On Tue, Mar 08, 2011 at 04:43:36PM +0800, Dave Young wrote:
> On Tue, Mar 8, 2011 at 4:24 PM, Alexey Dobriyan <adobriyan@gmail.com> wrote:
> > On Tue, Mar 08, 2011 at 01:43:31PM +0800, Dave Young wrote:
> >> On Tue, Mar 8, 2011 at 1:15 PM, Dave Young <hidave.darkstar@gmail.com> wrote:
> >> > On Tue, Mar 8, 2011 at 7:26 AM, Alexey Dobriyan <adobriyan@gmail.com> wrote:
> >> >> On Mon, Mar 07, 2011 at 03:05:43PM -0800, akpm@linux-foundation.org wrote:
> >> >>> Add a proc_dointvec_unsigned() sysctl handler for positive value cases.
> >> >>
> >> >>> --- a/kernel/sysctl.c~sysctl-add-proc_dointvec_unsigned-handler
> >> >>> +++ a/kernel/sysctl.c
> >> >>
> >> >>> +int proc_dointvec_unsigned(struct ctl_table *table, int write,
> >> >>> +               void __user *buffer, size_t *lenp, loff_t *ppos)
> >> >>> +{
> >> >>> +     struct do_proc_dointvec_minmax_conv_param param = {
> >> >>> +             .min = &zero,
> >> >>> +     };
> >> >>> +     return do_proc_dointvec(table, write, buffer, lenp, ppos,
> >> >>> +                             do_proc_dointvec_minmax_conv, &param);
> >> >>> +}
> >> >>
> >> >> This silently ignored max value in .extra2 .
> >> >
> >> > Hi,
> >> >
> >> > Good cache, should set .max = NULL here
> >>
> >> Oh, c99 set default value to 0, isn't it?
> >>
> >> What do you mean silently ignore here?
> >>
> >> Let's see the code:
> >>
> >>  if ((param->min && *param->min > val) ||
> >>                     (param->max && *param->max < val))
> >>                     return -EINVAL;
> >>
> >> There's no problem max == NULL
> >
> > I mean literally "silently ignore".
> >
> > Try
> >        {
> >                .name = "foo",
> >                .data = &foo,
> >                .maxlen = sizeof(foo),
> >                .proc_handler = proc_dointvec_unsigned,
> >                .extra2 = &_42,
> >        }
> >
> 
> Yes, extra2 is ignored,  what would you like to do for this kind of ignore?

Obviously it should remain upper bound.