Re: Locking problem in usbserial with 2.6.23-git 5a34417f

[Larry Finger <larry.finger@lwfinger.net>]

Jiri Kosina wrote:
> On Fri, 19 Oct 2007, Larry Finger wrote:
> 
>> While attempting to configure a new USB modem, the following locking 
>> problem occurred. In addition, shortly after this problem occurred, the 
>> computer froze. The log data starts at the point that usbserial was 
>> loaded and contains everything that was written to disk before the 
>> machine locked up. Some info may be missing from the end of the stack 
>> dump.
> 
> I guess this one is needed.
> 
> 
> From: Jiri Kosina <jkosina@suse.cz>
> 
> USB: usbserial - fix potential deadlock between write() and irq
> 
> usb_serial_generic_write() doesn't disable interrupts when taking port->lock,
> and could therefore deadlock with usb_serial_generic_read_bulk_callback()
> being called from interrupt, taking the same lock. Fix it.
> 
> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
> 

Yes, this patch did fix the locking problem.

Thanks,

Larry