Re: [PATCH 3/3] misc: use a proper range for minor number dynamic allocation

[Andrew Morton <akpm@linux-foundation.org>]

On Mon, 09 Nov 2009 16:34:07 -0800
"H. Peter Anvin" <hpa@zytor.com> wrote:

> On 11/09/2009 04:30 PM, Thadeu Lima de Souza Cascardo wrote:
> > The current dynamic allocation of minor number for misc devices has some
> > drawbacks.
> > 
> > First of all, the range for dynamic numbers include some statically
> > allocated numbers. It goes from 63 to 0, and we have numbers in the
> > range from 1 to 15 already allocated. Although, it gives priority to the
> > higher and not allocated numbers, we may end up in a situation where we
> > must reject registering a driver which got a static number because a
> > driver got its number with dynamic allocation. Considering fs/dlm/user.c
> > allocates as many misc devices as lockspaces are created, and that we
> > have more than 50 users around, it's not unreasonable to reach that
> > situation.
> > 
> > The proposed solution uses the not yet reserved range from 64 to 127. If
> > more devices are needed, we may push 64 to 16.
> > 
> 
> Again, why not push these up above 256?
> 

I merged this patch, but made a note-to-self that there are remaining
open issues..