Subject: kern/20585: GENERIC config COMPAT_1 option usage is (mostly) bogus
To: None <email@example.com>
From: None <kre@munnari.OZ.AU>
Date: 03/05/2003 17:09:06
>Synopsis: GENERIC config COMPAT_1 option usage is (mostly) bogus
>Arrival-Date: Wed Mar 05 02:11:00 PST 2003
>Originator: Robert Elz
>Release: NetBSD 1.6P (-current of 2003-03-03)
Prince of Songkla University
System: NetBSD fuchsia.cs.mu.OZ.AU 1.6P NetBSD 1.6P (FUCHSIA) #35: Wed Mar 5 13:50:03 ICT 2003 root@:/usr/obj/sys/FUCHSIA i386
Many (but not all) sys/arch/*/conf/GENERIC* files include
None of the sys/arch/*/conf/GENERIC* files include
Yet, COMPAT_15 is a (wholly) useless option - apart from the
various sys/arch/*/conf/* files the only place it appears is
in conf/files where it is defined. Nothing in the kernel
(in -current anyway) depends upon it in any way at all.
On the other hand, COMPAT_16 does exist - currently twice.
It is in arch/vax/vax/machdep.c (and is defined in
arch/vax/conf/GENERIC so that one is fine).
It is also in kern/subr_disk.c and so should be in all the
various ports' conf/GENERIC files - the lack of it is almost
certainly what causes so many people to bump into the
"bad sysctl" from iostat (as hw.diskstats changed).
But apart from those two, COMPAT_16 should also appear in
vast numbers of arch/x/x/*machdep.c files - and in a way
does, using the idiom
#if 1 /* COMPAT_16 */
which seems to date from the times when COMPAT_16 did not
yet exist, and someone was hoping not to have to add it...
Remove COMPAT_15 from everywhere except sys/conf/files
where it wants to remain so it remains a valid (useless) option
for people's private kernel config files. While that isn't
strictly necessary, it is a good idea to keep it there.
It should be in none of the distributed config files though.
Add COMPAT_16 to everywhere (GENERIC at least), except
vax/conf/GENERIC where it exists already. This is the
most important part of this PR (the rest is just cleanup).
#if 1 /* COMPAT_16 */
throughout (appears in arch/x/x/*machdep.c files for most x)
Document COMPAT_16 in options(4). (Note there is no COMPAT_15
there, so why everyone keeps using it is a mystery).
Whie cleaning up, a few ports' GENERIC files could perhaps lose
their COMPAT_09 compat_10 (etc) options, where they describe
versions of the kernel that never existed for the port in
question - and not just include them all "because everyone else