Re: FFS_ROOT is gone?

On Wed, Jul 16, 2003 at 01:47:59AM +0200, Harald Schmalzbauer wrote:
> Bernd Walter wrote:
> > On Tue, Jul 15, 2003 at 12:22:31PM -0700, Tim Kientzle wrote:
> > > Harald Schmalzbauer wrote:
> > > >The problem is solved. It was stupid, but I thought why should
> > I have to
> > > >set
> > > >/ in /etc/fstab when the filesystem isn't mounted yet, so the
> > file can't be
> > > >read.
> > > >But it seems the kernel reads this file "loader-like" *before* the
> > > >filesystem is mounted.
> > >
> > > I believe that the loader actually reads this file (it
> > > has to be able to locate and read files from UFS anyway
> > > in order to load the kernel) and passes the root f/s
> > > information to the kernel when it boots.  This should
> > > probably be documented in fstab(5)
> >
> > You can pass a filesystem at the loader prompt:
> > vfs.root.mountfrom=""
> >
> > > >Considering the above to be correct I can't understand the
> > ability to enter
> > > >e. g. ufs:/dev/ad0a at "mountroot>" when it doesn't work.
> > >
> > > I've also been stung by the fact that the
> > > "mountroot>" prompt is broken.  <sigh>
> > > I looked briefly at the code, but the
> > > bug is not particularly obvious.
> >
> > At least it wasn't broken a while ago.
> > What happens exactly after entering the correct device?
> 
> The machine rebooted. No matter if I did "?" or any "ufs:xxYz". It's
> behaviour was like "empty line".

That's the normal behavour if the line can't be parsed.
IIRC you can't correct typos on that line.
Even if a line corrected with backspace looks good - it is not.

> That was mine dunno about Tim's
> 
> Regarding loader reades /etc/fstab: Of course loader and even boot can read
> from ufs but I verified that current device was disk0s1 (where my 165-ID
> was) and also something like root-mount was set to disk0s1.
> 
> Next thing is that boot0 could'nt boot my kernel (5.1-release).
> Some time ago I built a little accesspoint with 4.6 and there was no problem
> booting the kernel with only boot0, no loader.
> 
> Has this feature been intentionally removed?

The loader sets variables that are required for the kernel to run
such as reading device.hints.
You can still compile the variables staticaly into the kernel and
directly use boot2 (boot0 is the bootmanager).

-- 
B.Walter                   BWCT                http://www.bwct.de
ticso_at_bwct.de                                  info_at_bwct.de