ubi deadlock on .36+

[Artem Bityutskiy]

On Sat, 2010-11-13 at 14:37 +0200, Artem Bityutskiy wrote:
> On Thu, 2010-11-04 at 15:07 +0200, Grazvydas Ignotas wrote:
> > On Thu, Nov 4, 2010 at 9:29 AM, Artem Bityutskiy <dedekind1 at gmail.com> wrote:
> > > On Wed, 2010-11-03 at 23:30 +0200, Grazvydas Ignotas wrote:
> > >> Hi,
> > >>
> > >> there seems to be some issue with NAND on my OMAP3 board that causes
> > >> CRC errors on 2.6.36 and 2.6.37-rc1. Those seem to be triggering a bug
> > >> in UBI that makes it loop forever (or very long) printing this:
> > >>
> > >> uncorrectable error :
> > >> UBI error: ubi_io_read: error -74 (ECC error) while reading 512 bytes
> > >> from PEB 0:512, read 512 bytes
> > >> uncorrectable error :
> > >> UBI error: ubi_io_read: error -74 (ECC error) while reading 512 bytes
> > >> from PEB 68:512, read 512 bytes
> > >> UBI: run torture test for PEB 68
> > >> UBI: PEB 68 passed torture test, do not mark it a bad
> > >>
> > >>
> > >> here is full log of one minute session, after which I killed power:
> > >> http://notaz.gp2x.de/misc/pnd/logs/linux_20101103_ubi_lockup
> > >
> > > Hmm, could you please enable UBI debugging and provide me the logs? See
> > > here for some hints:
> > > http://www.linux-mtd.infradead.org/doc/ubi.html#L_how_send_bugreport
> > 
> > done:
> > http://notaz.gp2x.de/misc/pnd/logs/linux_20101103_ubi_lockup2
> 
> But would it be possible to enable all UBI debugging messages?

While trying to figure out what is happening in your system, I realized
one possible scenario which may confuse UBI. I've added a patch below.
This probably won't fix your issue (but you could try), I need more time
to think about what was happening. But a log with all messages (not only
I/O) would help. Thanks.