Re: [PATCH] JMicron JM20337 USB-SATA data corruption bugfix - device 152d:2338

[Tomas Styblo <tripie@cpan.org>]

* Alan Stern <stern@rowland.harvard.edu> [Tue, 22 Jul 2008]:
> On Mon, 21 Jul 2008, Robert Hancock wrote:
> > > this message includes a patch that provides a workaround for
> > > a silent data corruption bug caused by incorrect error handling in
> > > the JMicron JM20337 Hi-Speed USB to SATA & PATA Combo Bridge chipset,
> > > USB device id 152d:2338.
> 
> The two of you should read through
> 
> 	http://bugzilla.kernel.org/show_bug.cgi?id=9638
> 
> which concerns this very problem.

I had found this bugreport and read through it before I posted my
patch. I don't think this is the same problem. The error messages
and the description of the problem are different from what I've
been trying to fix.

Anyway, I'll send the patch to this person so he can try it. 
I guess it won't fix his problem. This patch is much simpler and doesn't 
need any delays - I really think this is a different situation.

I sometimes experience the problems described by this person, as I
noted in the first message with the patch. When these "reset high
speed USB device" messages appear, it is usually necessary to
disconnect and power off the device. In my experience, data
corruption can be prevented in this situation by setting:

# tune2fs -e remount-ro /dev/sdX

But this is a different problem - in this situation the error
actually IS detected.



-- 
Tomas Styblo <tripie@cpan.org>