Re: File locking problems?

Matthias Urlichs (smurf@noris.de)
Mon, 3 Nov 1997 12:22:34 +0100 (Funky)

Hi,
>
>Matthias Urlichs writes:
>> Remove the locking code from mount and umount.
>> ln -s /proc/mtab /etc
>> ln -s /proc/mtab /var/run
>>
>> Bingo, the problem is gone.
>
>If I do that then I a message about /dev/root not being mounted when I
>run shutdown. Furthermore, as the man page says, doing that will make
>working with the loop device less convenient.
>
Right. If you need that, use a different solution. I can live without a
cleanly-looking loop device, and my shutdown script explicitly
read-only-remounts /var, /usr and /, just to be on the safe side.

I also modified my personal kernel so that a loop device is auto-dis-
associated from its file when it is closed, thus I never have to detach
looped-back files either manually or from within umount.

But that my personal preference. Linus didn't like it last time I submitted
that patch. *shrug*

>But, as I said, I disabled the code in mount which removes the
>/etc/mtab~ lockfile. This means that the fcntl() locking will always
>work on the same file. Or is there some other effect going on?

Hmmm. Which file does your mount use to write the new mtab records to, then?

-- 
Matthias Urlichs
noris network GmbH