Subject: kern/13861: nullfs can't be remounted ro/rw
To: None <firstname.lastname@example.org>
From: None <email@example.com>
Date: 09/03/2001 23:09:04
>Synopsis: nullfs can't be remounted ro/rw
>Arrival-Date: Mon Sep 03 06:05:01 PDT 2001
>Originator: matthew green
>Release: <NetBSD-current source date>today
people's front against (bozotic) www (softwar foundation)
System: NetBSD madrugada.eterna.com.au 1.5W NetBSD 1.5W (_madrugada_) #97: Fri Aug 17 01:27:38 EST 2001 firstname.lastname@example.org:/var/_madrugada_ alpha
the nullfs code doesn't allow one to remount a filesystem and change
the read-write / read-only mode. one is forced to unmount and remount,
which means it can't be done on an active filesystem.
mount /usr/src as read-only nullfs. after you've finished a build and
want to modify sources, attempt to mount -u -o rw /usr/src and fail.
write the code to support this in nullfs. i had a look but i'm going
to leave this one to someone else....