bug#22050: [PATCH v3 1/2] linux-boot: Add make-static-device-nodes.

[Danny Milosavljevic]

Hi Ludo,

On Thu, 14 Dec 2017 14:14:09 +0100
address@hidden (Ludovic Courtès) wrote:

> The code would be slightly simpler (no pipe, etc.), and the .devname
> file might be more stable than the kmod output, being a kernel
> interface.
> 
> WDYT?

That's true.  The kernel interface definitely has Linus breathe down the neck 
of anyone who even thinks of changing it :)

> >> What about having a ‘static-device-nodes’ procedure that would parse
> >> that and return a list of <device-node>, where:
> >> 
> >>   ;; TYPE is 'char or 'block, MAJOR and MINOR are integers.
> >>   (define-record-type <device-node>
> >>     (device-node name type major minor module)
> >>     device-node?
> >>     …)
> >> 
> >> and then:
> >> 
> >>   (define create-device-node
> >>     (match-lambda
> >>       (($ <device-node> name type major minor)
> >>        (mknod …))))
> >> 
> >> finally:
> >> 
> >>   (for-each create-device-node (static-device-nodes))
> >> 
> >> ?  
> >
> > The kmod format has entries not only for mknod but also for mkdir (it 
> > actually mkdirs the same directory twice sometimes which is why there was 
> > another version of this patch...).  
> 
> OK, I had overlooked that.  Hopefully the general approach remains
> valid?

Yeah.  Apparently kmod autogenerates those when there's a slash in the name it 
got from the devname file.  That's why it generates two mkdir entries for "snd" 
- there's a "snd/timer" and a "snd/seq" in the devname file...