Re: usb-serial ipaq kernel problem

[Luiz Fernando N. Capitulino]

On Tue, 30 May 2006 11:38:01 -0300
"Luiz Fernando N. Capitulino" <lcapitulino@xxxxxxxxxxxxxxx> wrote:

| On Tue, 30 May 2006 10:21:41 +0200
| Frank Gevaerts <frank.gevaerts@xxxxxx> wrote:
| 
| | On Mon, May 29, 2006 at 07:33:30PM -0300, Luiz Fernando N. Capitulino wrote:
| | > On Mon, 29 May 2006 22:47:24 +0200
| | > Frank Gevaerts <frank.gevaerts@xxxxxx> wrote:
| | > | 
| | > | The panic was caused by the read urb being submitten in ipaq_open,
| | > | regardless of success, and never killed in case of failure. What my
| | > | patch basically does is to submit the urb only after succesfully sending
| | > | the control message, and adding a sleep between tries. As long as this
| | > | patch is not applied, we hardly get any other error because the kernel
| | > | panics as soon as an ipaq reboots.
| | > 
| | >  I see.
| | > 
| | >  Did you try to just kill the read urb in the ipaq_open's error path?
| | 
| | Yes, that's what I did at first. It works, but with the long waits (we see
| | waits up to 80-90 seconds right now) I was afraid that the urb might timeout
| | before the control message succeeds.
| 
|  Hmmm, I see.

 Thinking about this again, are you sure the read urb depends on the
control message? It's quite easy to test, just a add a long timeout after
the read URB was sent (say, five minutes) and waits for the read urb
callback to run.

 If it ran _before_ the timeout expires with no timeout error it does not
depend. Then we can do the simpler solution: just kill the read urb in the
ipaq_open's error path.

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