-- Charles

On Friday 20 April 2007 21:36, you wrote:
> On Thursday 19 April 2007 21:54, Charles Manning wrote:
> > That would suggest to me that somehow the yaffs short op cache is screwed
>
> up.
>
> > The dd's you do:
> > #dd if=/dev/zero of=/nand0/test1 bs=2k count=xxx
> >
> > are chunk aligned which means that you're bypassing the cache.
> > If that theory holds, then
> > #dd if=/dev/zero of=/nand0/test1 bs=2k count=1000
> > will work and it is not a file size issue.
>
> It works.
>
> > What happens if you do
> > #dd if=/dev/zero of=/nand0/test1 bs=1k count=10
>
> That works, too!
>
> > That would force yaffs to use the cache and, I suspect might cause the
>
> crash.
>
> But using a block size bigger or equal to 4k crashes the system:
> #dd if=/dev/zero of=/nand0/test1 bs=4k count=10
>
> Exactly 4095 bytes is still ok:
> #dd if=/dev/zero of=/nand0/test1 bs=4095 count=10
>
> > If this is happening then it is probably because the cache is not being
> > allocated correctly and unfortunately there are insufficient checks in
> > place to see that the malloc succeeded. There is some stuff I am working
> > on that fixes this and other issues but that won't be checked in for a
> > while.
> >
> > Something else to try would be do look in yaffs_fs.c for where
> > dev->nShortOpCaches is assigned and set that to zero. That turns off the
> > internal cache.
>
> I did the same tests with internal cache turned off. But it had no impact
> on the issue.
>
> Matthias