From: Pavel Roskin <proski@gnu.org>, via Christoph Hellwig <hch@infradead.org>

It's already the second time that I encounter a kernel panic in the same
place.  When devfs_remove() is called on a non-existent file entry, the
kernel panics and I have to reboot the system.

First time it was unregistering of pseudoterminals.  This time it's
ide-floppy module that doesn't register devfs entries if the media is absent
but still tries to unregister them.  The bug in ide-floppy will be reported
separately.

The point of this message is that the failure in devfs_remove() is possible,
especially with rarely used drivers.  Secondly, is not fatal enough to
justify an immediate panic and reboot.  Thirdly, devfs misses a chance to
tell the user what's going wrong.