Matt Fleming | 1 Apr 2008 14:06
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Re: mjf-devfs2 branch


On Mon, Mar 31, 2008 at 11:29:46PM +0100, Andrew Doran wrote:
> On Sat, Mar 29, 2008 at 04:35:31PM +0000, Matt Fleming wrote:
> 
> > Further Work:
> > 	- Once device drivers are all converted, move to dynamic major
> >  	  numbers
> 
> It seems like a lot of this naturally belongs in the device switch and that
> the same call should register the device methods. Are you proposing to keep
> the existing major numbers? That makes sense in the short term but longer
> term I think we'd be making a mistake by doing that.
> 

I haven't yet looked into this fully, mainly because it's the last stage
of the project. However, mrg has pointed out that we already support
dynamically assigning major numbers because the switch tables can be built
dynamically at run time. If I recall correctly he mentioned he made this
work with LKMs.

When we make the switch I wasn't proposing to keep the existing major
numbers, I'm not aware of any problems that would be introduced by having
different ones. That's not to say there won't be any. As long the upgrade
procedure for new devfs installs is sane and we can take account of 
people's customisations of device nodes, everything _should_ be fine.

--mjf

Gmane