Re: [PATCH] add kernel parameter to disable module load

[Rusty Russell <rusty@rustcorp.com.au>]

On Tue, 31 Jan 2012 10:44:50 +0800, Dave Young <dyoung@redhat.com> wrote:
> On 01/29/2012 08:51 AM, Rusty Russell wrote:
> 
> > On Sat, 28 Jan 2012 11:34:50 +0800, Dave Young <dyoung@redhat.com> wrote:
> >> Sometimes we need to test a kernel of same version with code or config
> >> option changes.
> >>
> >> We already have sysctl to disable module load, but add a kernel
> >> parameter will be more convenient.
> > 
> > 
> >> +static int __init module_load_disable(char *str)
> >> +{
> >> +	modules_disabled = 1;
> >> +	return 1;
> >> +}
> >> +__setup("nomodule", module_load_disable);
> > 
> > You misspelled core_param here :)
> > 
> 
> 
> Hello Rusty, If use core_param I'd better to change modules_disabled
> from int to bool or we must pass nomodule=1 instead of simply pass
> nomodule. But I think I can firstly post the core_param patch with
> current int type, then work on the transition patch for the variable
> type changes, what do you think?

You could code your set function, but "bint" is what you want.  Cleaning
it up to be a bool is a good idea too.

> Another do you think we need to expose this to sysfs via core_param?
> According to the sysctl code looks like we should not add sysfs
> interface to allow transition from "1" to "0"

If you want it writable, you definitely want to code your own set
function so it's one way.  But perm 0 or 0444 make sense, too.

Cheers,
Rusty.