Subject: kern/31029: pppd easily get in 100% CPU loop in -current
To: None <kern-bug-people@netbsd.org, gnats-admin@netbsd.org,>
From: None <wojtek@tensor.3miasto.net>
List: netbsd-bugs
Date: 08/21/2005 20:54:00
>Number:         31029
>Category:       kern
>Synopsis:       pppd easily get in 100% CPU loop in -current
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Aug 21 20:54:00 +0000 2005
>Originator:     Wojciech Puchar
>Release:        -current 2 weeks ago
>Organization:
TENSOR ap
>Environment:
NetBSD chylonia.3miasto.net 3.99.7 NetBSD 3.99.7 (chylonia.3miasto.net.mp) #0: Sun Aug 21 20:17:28 CEST 2005  root@chylonia.3miasto.net:/usr/src/sys/arch/i386/compile/chylonia.3miasto.net.mp i386

or
NetBSD serwer.3miasto.net 3.99.7 NetBSD 3.99.7 (3miasto.net) #3: Sun Aug 21 15:05:10 CEST 2005  root@:/usr/src/sys/arch/amd64/compile/3miasto.net amd64


>Description:
pppd works fine on leased line only when both sides responds.

in case of one peed inactive pppd quickly (less than a minute) gets into 
100% CPU loop state, in which it stops responding to peer too.

my ppp config looks like that:

tty02
921600
local crtscts
netmask 255.255.255.255
maxfail 0
#deflate 15
nodeflate
persist noauth defaultroute nobsdcomp 
noproxyarp
+ipv6

peer (master) looks similar just with IPv4 addresses specified

it worked fine with 2.0.2, doesn't work in -current and it's most probably kernel bug so i classified is as kern
>How-To-Repeat:
use pppd with leased line (with local option not modem) and kill pppd on one peer. second peer will quickly go into 100% CPU state. rerunning pppd 
on first peer don't negotiate things again and... quickly goes to 100% CPU state too :(

>Fix:
none