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

[Greg KH <greg@kroah.com>]

On Wed, Mar 26, 2003 at 07:25:20PM +0000, Chris Sykes wrote:
> 
> I seem to have worked around it for now.  I've jumpered the hardware
> to stop it from echoing what you transmit back locally and all seems
> OK now.

Good.

> > Can you test 2.5 to see if this is fixed there for you or not?
> 
> I can test it yes, but 2.5 may be a bit too unstable for our
> production use ATM.

I understand.

> 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.

thanks,

greg k-h