On Fri, May 21, 2004 at 03:29:21PM -0400, Steven M. Bellovin wrote:
> In message <20040521192041.GA807@antioche.eu.org>, Manuel Bouyer writes:
> >On Sat, May 22, 2004 at 04:58:30AM +1000, Daniel Carosone wrote:
> >> [...]
> >> Another workaround, and interesting test, would be to turn off
> >> write-cache on the drive:
> >> 
> >> 	dkctl wdX setcache r
> >> 
> >> and then try the unmount.  I'm hoping/assuming this would wait for the
> >> superblock write to complete.  Could you try this?  If it does, then
> >> building the moral equivalent of
> >> 
> >> 	dkctl wdX synccache force
> >> 
> >> into the close is the right way to fix this.  It even seems to me like
> >> if we don't do this, there might be other similar lossage cases
> >> lurking than the pcmcia one you found.
> >
> >There is already wd_flushcache() on last close in wd.c. This should be enouth.
> >
> 
> I assume that I still need to do the 'setcache r', correct?

Would be a good test. But this flush cache command should be enouth.
Maybe adding a printf here to make sure it's called on last close would
be usefull too.

Also please update to wd.c 1.276, I just added support for DIOCCACHESYNC.
Then you can try dkctl wdX synccache, and see if it complete without errors.

-- 
Manuel Bouyer <bouyer@antioche.eu.org>
     NetBSD: 26 ans d'experience feront toujours la difference
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