[linux] vfs: cannot open root device

[Peter Abrahamsen]

The thing that always gets me is I compile a custom kernel on a new box,
turn on devfs support (at boot), and forget to install devfsd before I
reboot. In that case, I have to pass
 root=/dev/ide/host0/bus0/target0/lun0/part1 s
to the kernel, boot into single-user mode, and install devfsd and/or fix
/etc/fstab.

Peter

On Mon, Jul 07, 2003 at 11:34:00AM -0700, Jonathan Nicol wrote:
> Heya Parker,
> 
> I'm kinda throwing things out here, but maybe this will get you on the
> right track.
> 
> Do you have "/dev file system support" compiled into the kernel? I recall
> it being off by default (maybe even marked experimental?) And all
> appropriate IDE (or scsi) drivers?
> 
> Perhaps posting your grub.conf would help...
> 
> And, as a slightly more drastic possible solution, you could run 'make
> mrproper' from /usr/src/linux (or where ever your kernel source is). This
> will clean up EVERYTHING, including your config, so you'll have to start
> over.
> 
> 
> -Jonathan
> 
> On Sun, 6 Jul 2003, Parker Thompson wrote:
> 
> > I am having a problem getting a custom kernel to load and am completely
> > baffled by it.
> >
> > I installed redhat 9 on my inspiron 2100.  I then grabbed the latest
> > source (2.4.21) from kernel.org, untarred it, patched the orinoco/hermes
> > drivers (for monitor mode), ran make xconfig, and ran 'make dep && make
> > make && make bzImage && make modules && make modules_install'.  I then
> > copied the newly created bzImage and System.map to /boot, created an
> > initrd like so:
> >
> >   mkinitrd --fstab=/etc/fstab initrd-2.4.21 2.4.21
> >
> > copied it to /boot, and created an appropriate entry in grub.conf.
> >
> > However, when I try to boot the new kernel I get the message:
> >
> >   VFS: Cannot open root device "LABEL=/" or 00:00
> >
> > followed by the obligatory kernel panic.  The partition is ext3, for which
> > I have built support into the kernel, so that is not the problem.  The
> > root partition is /dev/hda1, and grub is looking at hd0,0, which should be
> > fine (and mirrors my working kernel's config).
> >
> > Of note, some people who experienced similar problems have fixed them by
> > replacing / with /dev/hda1 in grub.conf, however this did not work for me.
> > I have also seen vague discussions of acpi causing problems, however
> > passing the kernel acpi=off from grub had no effect in my case.
> >
> > Also worth mentioning, removed .config in my source root, ran make clean,
> > and built a kernel with all default options (and excluding the orinoco
> > patch), and encountered this same problem.  Hopefully that eliminates the
> > possibility I just fouled up the configuration.
> >
> > Perhaps I'm just missing something silly, it's been a long time since I've
> > compiled my own kernel (slacker I know), but I have run out of ideas and
> > it ceased to be interesting and started to become annoying after a couple
> > of hours.
> >
> > Thanks much for any insight,
> >
> > pt.
> > ----------------------------------------------------------
> > >From a Sun Microsystems bug report (#4102680):
> > "Workaround: don't pound on the mouse like a wild monkey."
> >
> >
> >

-- 
Peter Abrahamsen              Seattle, Washington, USA
CEP, Phil, iSchool            http://www.abrahamsen.com/peter/
University of Washington      206.664.0390 (home)
"Hey, Monkey, what d'you think? Doesn't the guy ever wonder why the
 trucks don't /arrive/!" And she, wide-eyed, flutter-voiced:
"Man, do you suppose ... maybe they /do/!"