Re: kernel BUG at sched.c:564! (2.4.20, 2.4.21-pre5-ac3)

From: Chris Sykes (chris@sigsegv.plus.com)
Date: Thu Mar 27 2003 - 06:16:00 EST


On Wed, Mar 26, 2003 at 11:34:37AM -0800, Greg KH wrote:
> > Anyway I'll test out a 2.5 kernel when I'm back in the office
> > tomorrow, I can devote some time to tracking down the problem if you
> > can give me some pointers on where to start. I'd like to be able to
> > feel confident that this will work reliably under 2.4, otherwise I
> > guess I need to look for alternate solutions.
>
> The problem is in the race on close() in the usb-serial.c code. In 2.5
> that logic has been rewritten to (hopefully) get rid of the race. That
> is what will need to be backported, once people test that this fixes the
> issue.

OK. 2.5.66 compiled and booted.

I've jumpered the hardware back to how it was originally when I
experienced the problem.
I've been working happily for about 10 mins with:

while /bin/true; do
        for i in *; do
                cat $i >/dev/ttyUSB0
        done
done

No Oopsen or errors in dmesg as yet. (Before I was getting many errors
about 0 size writes).

I can keep working under 2.5.66 for now to see if I experience any
problems, but it would appear that the race is gone in 2.5.66
(CONFIG_PREEMPT=y)

If you'd like me to try any patches against 2.4 just let me know.

Thanks again,

-- 

(o- Chris Sykes -- GPG Key: http://www.sigsegv.plus.com/key.txt //\ "Don't worry. Everything is getting nicely out of control ..." V_/_ Douglas Adams - The Salmon of Doubt


- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Mon Mar 31 2003 - 22:00:27 EST