Re: 2.9.29.2: ide-tape: panic when probing device at boot

[Borislav Petkov <petkovbb@googlemail.com>]

Hi,

On Mon, May 18, 2009 at 03:02:59PM +0930, Jonathan Woithe wrote:
> > On Sat, May 09, 2009 at 05:57:49PM +0200, Bartlomiej Zolnierkiewicz wrote:
> > > 
> > > [ cc:ing linux-ide and knowledgeable people ]
> > > 
> > > Borislav/Tejun:
> > > Is the 2.6.29 problem the same thing that was fixed recently?
> > 
> > I'll let Tejun answer that one since I don't get an oops. However, now
> > that I have an ide-tape hardware here, I do get something DMA-related
> > failing during boot ...
> > :
> > and more specifically the bad DMA info in identify block thing above. I
> > haven't looked into it yet but its next on my TODO.
> 
> Cool.
> 
> > > Should I just push commit 1e75540ec5202cae63cd238c86bd880e3d496546
> > > ("ide-tape: remove back-to-back REQUEST_SENSE detection") to Linus
> > > or there is more needed to bring ide-tape to the world of living?
> >
> > The oops will probably fixed the above commit.  I don't have much idea
> > about the DMA problem on 2.6.24 tho.  But even with the above commit
> > fixed, I doubt it would work.  The buffer allocation code is broken
> > and reliably triggered OOM on my test machine.  While trying to locate
> > the bug, I realized the complex code didn't do much good to begin with
> > and just stripped it down, so I didn't actually tracked down the
> > actual bug && the patch to simplify buffer management is way too large
> > for 2.6.29, so unless someone is willing to hunt down the bug just for
> > 2.6.29, we're kind of stuck.  :-(
> 
> So I take it that 2.6.30 (or one of the RCs) is worth trying (at least in so
> far as preventing the oops on boot)?

You could try 30-rc6 which runs pretty stable on my machines. It has the
patch mentioned above in it. At least one user confirmed that it fixes
ide-tape in his case. In case you still catch any OOPSes/warnings etc
please send me the whole dmesg output along with how you trigger them.

> > ... and I'm afraid we'll have to do some serious bugfixing since this
> > driver is behaving really funny :). Stay tuned, I'm on it.
> 
> Ok, I'll keep an eye out for updates.  Presumedly we're talking 2.6.31 or
> .32 here.

Already in .31-rc1 there's will more patches cleaning up ide-tape so if you
could try that and send us bug reports will be simply swell :).

Thanks.

-- 
Regards/Gruss,
    Boris.