Date: Wed, 8 Mar 2017 10:45:26 +0100
From: Greg KH <gregkh@linuxfoundation.org>
To: Cheah Kok Cheong <thrust73@gmail.com>
Cc: devel@driverdev.osuosl.org, abbotti@mev.co.uk,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/2] Staging: comedi: comedi_fops: Change
 comedi_num_legacy_minors type
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On Wed, Mar 08, 2017 at 05:38:12PM +0800, Cheah Kok Cheong wrote:
> Dear Greg,
>   Thanks for taking the time to review.
> 
> On Tue, Mar 07, 2017 at 08:01:38PM +0100, Greg KH wrote:
> > On Sun, Mar 05, 2017 at 03:22:32AM +0800, Cheah Kok Cheong wrote:
> > > Change to unsigned to allow removal of negative value check in
> > > init section.
> > 
> > Why?
> > 
> 
> User can input a -ve number as parameter for module loading.

Then they are foolish to do so :)

> This will be caught by the mentioned check and cause loading to fail.
> I think the original intention here is to inform user via kernel log
> the acceptable input range.

Either is fine.

> Now if a user doesn't know how to access the log, it's of no help.

They know how to set a module parameter as root but do not know of the
kernel log?  That's trying a bit too hard :)

> If a user does know how to access the log, probably also know how
> to use modinfo or know that reserving a -ve number of minors is
> not acceptable.
> 
> IMHO, this check is pointless and best enforced in module_param.

Ok, but it's really a minor, or no, real issue at all here.

thanks,

greg k-h