Re: Floppy problem

Greg Alexander (
Mon, 6 Jan 1997 23:37:33 -0500 (EST)

On Sun, 22 Dec 1996, Alain Knaff wrote:

> >Yes, you can do all sorts of gyrations with the disk. You have to do
> >exactly what I described to be hit by a panic: change the disk for
> >another and then access the disk. Any other fooling around accomplishes
> >nil. Actually, accessing the disk while it is removed will yield the
> >affected floppy unit useless and a D state process.
> The type of the mounted filesystem may also be important. When a
> disk is removed when mounted, the floppy driver has not many choices
> except to report to the upper layers (filesystem code) that there is a
> problem. Some filesystems (minix ?) seem to not handle this situation
> gracefully, and panic if they get any errors. Others (ext2 ?) do it
> the correct way, and just remount themselves readonly if a "fatal"
> error occurs. This prevents further corruption to the disk, but still
> allows the user to work with other parts of the system.

This is not always true. At one time I had an ext2fs that was in my mtab
to be mounted under /scrap. It had no important files in it and,
excepting my mtab and my fsck -A line, it wasn't referenced at all. I was
doing some funny partition stuff because I wanted to format that partition
as DOS or something (I forget) regardless, my partition table got screwed
and that partition wasn't the right size (my root partition was still
fine, though). Somewhere in bootup (I forget if it was in my mount or
fsck), I got a panic from this situation and I had to boot from a floppy
too modify /etc/mtab. ext2 does _not_ always handle errors in an
admirable way.

Greg Alexander