Re: init's MAKEDEV vs. postinstall fix (old tty nodes)

[Thomas Klausner <tk%giga.or.at@localhost>]

On Fri, Mar 27, 2020 at 10:28:17AM +0000, Robert Swindells wrote:
> On 2020-03-27 07:36, Thomas Klausner wrote:
> > 
> > With a tmpfs /dev init calls:
> > 
> >      "MAKEDEV -MM init"
> > 
> > (see sbin/init/init.c starting from line 1704)
> > 
> > which calls
> >         makedev all opty
> > 
> > of which opty does
> > 
> > opty)
> >         # Create 16 device nodes, [pt]typ0 to [pt]typf
> > ...
> >                 mkdev ttyp$j c 5 $jn 666
> >                 mkdev ptyp$j c 6 $jn 666
> > 
> > 
> > On the other hand, "postinstall fix" does:
> > 
> > ptyfsoldnodes fix:
> >         Removed legacy device node /dev/ptyp0
> >         ...
> >         Removed legacy device node /dev/ttypf
> > 
> > 
> > So my question is: if "postinstall fix" removes these devices on an
> > upgrade, why does init still create them?
> > 
> > This looks inconsistent. Which of the two should be changed?
> 
> Maybe not change either.
> 
> Running 'postinstall check' on a system that isn't using ptyfs doesn't flag
> the legacy
> nodes as needing deleting. I don't use ptyfs, and haven't tried telling
> postinstall to
> fix things other than those that 'postinstall check' recommends.

I just run 'postinstall fix' too.

> Does the tmpfs /dev have a ptyfs mounted below it at the time MAKEDEV is run
> ?

I'm not sure. It's in my fstab:
ptyfs           /dev/pts        ptyfs   rw
but I don't know when that is read compared to init.
 Thomas