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Description of problem:
When pppd exits - in our case when the Speedtouch USB ADSL Modem
userspace driver/software sends a kill -15 to close an ADSL connection
- it doesn't cleanly terminate its processes, instead it gets into an
infinite loop, presumably causing a stack overflow (see log below, the
termination message repeats 12632 times).

This, in turn, prevents any scripts (ip-down etc.) running as they
should after ppp exits.

The bug is described, along with single line fix, at:
http://marc.theaimsgroup.com/?l=linux-ppp&m=107498594022952&w=2

It's also fixed in ppp 2.4.2beta3.

Version-Release number of selected component (if applicable):
ppp-2.4.2-3.FC2.1

How reproducible:
Always

Steps to Reproduce:
1. establish ppp connection (USB Speedtouch ADSL modem, userspace driver)
2. send pppd process kill -15
3. 
    

Additional info:

/var/log/messages :

Aug  3 19:29:59 norbus pppd[2319]: Terminating on signal 15.
Aug  3 19:30:02 norbus last message repeated 12632 times
Aug  3 19:30:02 norbus pppoa3[2305]: Error reading from source device
Aug  3 19:30:02 norbus pppoa3[2305]: Woken by a sem_post event -> Exiting
Aug  3 19:30:02 norbus pppoa3[2305]: Write to usb Canceled
Aug  3 19:30:02 norbus pppoa3[2305]: Exiting
Aug  3 19:30:02 norbus kernel: Badness in local_bh_enable at
kernel/softirq.c:136
Aug  3 19:30:02 norbus kernel:  [<0211ae78>] local_bh_enable+0x39/0x56

[call trace follows]