Subject: kern/4854: umount -f doesn't always work.
To: None <>
From: Perry E. Metzger <>
List: netbsd-bugs
Date: 01/20/1998 21:34:48
>Number:         4854
>Category:       kern
>Synopsis:       umount -f doesn't always work.
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people (Kernel Bug People)
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Jan 20 18:50:01 1998
>Originator:     Perry E. Metzger
Perry Metzger
>Release:        NetBSD-1.3
System: NetBSD 1.3 NetBSD 1.3 (JEKYLL) #0: Tue Dec 30 19:09:14 EST 1997 i386

umount -f is supposed to "force" an unmount. Last night, I
attempted to unmount a floppy disk that was suffering from
severe i/o errors -- umount -f failed to unmount the device,
as the kernel still wished to write metadata to the disk before
unmounting (which it could not do.)
screw up a floppy. mount it. note that you need to reboot to unmount
the thing.
I'm guessing that "-f" just means "screw any processes with open files
on the partition" but still attempts metadata writes. There should be
some way for the kernel to just punt on those if they fail.