On Sun, Jan 17, 2016 at 01:01:23PM +0700, Robert Elz wrote:
> Date: Sat, 16 Jan 2016 23:27:51 +0100
> From: Manuel Bouyer <bou...@antioche.eu.org>
> Message-ID: <20160116222751.ga2...@asim.lip6.fr>
>
> | Also, you don't address the problem that, as I understand it and if
> | the code works properly, vnconfig -l won't show free devices if the
> | first 4 are in use.
>
> Arguably it shouldn't show any free devices at all, otherwise, where
> should it stop? The correct answer to "which vnd is free?" is "any
> vnd that is not is use." Attempting to enumerate them all is folly.
This is how vnconfig -l has been working for a long time.
>
> The current scheme (I believe) lists a vnd as free (not in use) if
> some higher vnd is (or has been) used, and stops when the highest one
> ever used is reached. Or at least that's the intent. But removing
> all of the output for unused vnds would probably be a good idea.
>
> If you want to know what is configured in /dev, then "ls /dev/vnd*d"
> will show you that, but there is no particular reason that vnd's
> (or any devices) need to exist in /dev (consider in a chroot partition,
> which might have /dev/vnd23[a-p] only)
This is how the netbsd-7 vnconfig -l is working (I've not looked at older
releases). It enumerates the vnd devices in /dev/ and queries the kernel
only for them.
HEAD has been changed, which means that HEAD won't list free devices
which exists in /dev. I think this behavior is brocken.
>
> There original problem was caused with the way vn{d}config was hacked
> to handle -l when vnd was made cloning (that lost backward compat to
> netbsd 6, which was the bug reported which the fixes in question were
> handling). But there was no way to fix vnd and vn{d}config that would
> retain 100% backward compat in all cases. Since NetBSD 7 was so new,
> some compat was lost just for it, you really do not want to run vnd
> related stuff from netbsd 7 release except with everything from its
> own version - upgrade to what is now on the relevant branch, or what
> is in current, but do both vnd.c and vndconfig at the same time.
We are running a vnconfig from netbsd-7. netbsd-7 vnconfig was broken to
fix a problem with netbsd-7 kernel+netbsd-6 userland. This is inacceptable.
On netbsd-7, vnconfig -l was working fine before the kernel change.
(and now HEAD doens't even list free devices).
In addition it seems that in some case, vnconfig fails to configure
a free device.
--
Manuel Bouyer <bou...@antioche.eu.org>
NetBSD: 26 ans d'experience feront toujours la difference
--
