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Re: [PATCH 1/2] Staging: comedi: comedi_fops: Change comedi_num_legacy_minors type

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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.
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.

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

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.
 
> > Use smaller data type since the max possible value currently is 48.
> 
> Does it matter?
> 

You are right it doesn't matter and not worth the effort doing unless
concurrent work is being done in this area.
Which is what patch 2/2 is trying to do here.
Please note that I've sent V2. Patch 1/2 unchanged and 2/2 with amended
commit log.

Thanks,
Brgds,
CheahKC

> thanks,
> 
> greg k-h

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[PATCH 1/2] Staging: comedi: comedi_fops: Change comedi_num_legacy_minors type Cheah Kok Cheong <thrust73@gmail.com> - 2017-03-04 20:30 +0100
  [PATCH 2/2] Staging: comedi: comedi_fops: Fix "out of minor numbers for board device files" Cheah Kok Cheong <thrust73@gmail.com> - 2017-03-04 20:30 +0100
    Re: [PATCH 2/2] Staging: comedi: comedi_fops: Fix "out of minor  numbers for board device files" Dan Carpenter <dan.carpenter@oracle.com> - 2017-03-08 07:00 +0100
      Re: [PATCH 2/2] Staging: comedi: comedi_fops: Fix "out of minor  numbers for board device files" Cheah Kok Cheong <thrust73@gmail.com> - 2017-03-08 11:20 +0100
        Re: [PATCH 2/2] Staging: comedi: comedi_fops: Fix "out of minor  numbers for board device files" Ian Abbott <abbotti@mev.co.uk> - 2017-03-08 12:20 +0100
          Re: [PATCH 2/2] Staging: comedi: comedi_fops: Fix "out of minor  numbers for board device files" Cheah Kok Cheong <thrust73@gmail.com> - 2017-03-08 18:10 +0100
  Re: [PATCH 1/2] Staging: comedi: comedi_fops: Change  comedi_num_legacy_minors type Greg KH <gregkh@linuxfoundation.org> - 2017-03-07 20:10 +0100
    Re: [PATCH 1/2] Staging: comedi: comedi_fops: Change  comedi_num_legacy_minors type Greg KH <gregkh@linuxfoundation.org> - 2017-03-08 11:20 +0100
      Re: [PATCH 1/2] Staging: comedi: comedi_fops: Change  comedi_num_legacy_minors type Cheah Kok Cheong <thrust73@gmail.com> - 2017-03-08 11:20 +0100
    Re: [PATCH 1/2] Staging: comedi: comedi_fops: Change  comedi_num_legacy_minors type Cheah Kok Cheong <thrust73@gmail.com> - 2017-03-08 11:40 +0100

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