Date: Fri, 10 Nov 1995 10:01:59 +0100 (MET) From: J Wunsch <j@uriah.heep.sax.de> To: jkh@time.cdrom.com (Jordan K. Hubbard) Cc: joerg_wunsch@uriah.heep.sax.de, freebsd-hackers@freebsd.org Subject: Re: ideas from netbsd Message-ID: <199511100901.KAA05276@uriah.heep.sax.de> In-Reply-To: <2119.815969113@time.cdrom.com> from "Jordan K. Hubbard" at Nov 9, 95 06:05:13 pm
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As Jordan K. Hubbard wrote: > > > > All I know is that if I fork a shell before I chroot to /mnt (the hard > > > disk), I can never use the floppy again.. > > > > What is ``never use again'' exactly? > > It's busy. Any attempt to open /dev/fd0 again will fail. Perhaps a floppy driver problem. I will have to see if i could isolate the problem. Forcibly unmounting didn't help? (mount -f) Yeah, i know why it's busy (and yes, forcibly unmounting would help)! If a device is accessible by different vnodes (that all have identical major and minor #'s), the kernel won't let you unmount a file system containing one of these vnodes. You can easily verify this by mounting a ufs floppy (or perhaps even a vn or mfs device), then copying the entire /dev there (as you would do it e.g. for the copy of a boot floppy). Any attempt to unmount it will be rejected (since there are now some device nodes on it that are also open inside the original /dev tree). Forcibly unmounting helps, and doesn't harm since the open descriptors refer to nodes that have not been opened from the floppy. Hmm, i'm not sure if it would also help in the installer case, the question is which descriptors are still being held open, and what would happen if they are being revoked by the umount -f. If they are stale anyway, it doesn't hurt. If they are really active, it would break everything... -- cheers, J"org joerg_wunsch@uriah.heep.sax.de -- http://www.sax.de/~joerg/ -- NIC: JW11-RIPE Never trust an operating system you don't have sources for. ;-)
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