Re: port-amd64/56844

[ocb%l25.fi@localhost]

The following reply was made to PR port-amd64/56844; it has been noted by GNATS.

From: ocb%l25.fi@localhost
To: gnats-bugs%NetBSD.org@localhost
Cc: martin%duskware.de@localhost
Subject: Re: port-amd64/56844
Date: Wed, 18 May 2022 19:35:24 +0000

 Excuse me for not being clear.
 
 All devices named below are physical devices.
 
 192.168.88.1 - mikrotik router
 192.168.88.2 - mikrotik antenna connected to PoE port 10 on the router
 192.168.88.252 - netbsd workstation connected to port 6 on the router
 
 Network configuration was made according to ifconfig.if(5), and all network connectivity with local devices and remote hosts works as expected.
 
 dc$ cat /etc/ifconfig.wm0
 up
 inet 192.168.88.252 netmask 255.255.255.0
 !route add 192.168.88.2 192.168.88.1
 
 dc$ cat /etc/rc.conf | grep -E 'defaultroute'
 defaultroute="192.168.88.2"
 
 dc$ ifconfig wm0
 wm0: flags=0x8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
         capabilities=7ff80<TSO4,IP4CSUM_Rx,IP4CSUM_Tx,TCP4CSUM_Rx>
         capabilities=7ff80<TCP4CSUM_Tx,UDP4CSUM_Rx,UDP4CSUM_Tx,TCP6CSUM_Rx>
         capabilities=7ff80<TCP6CSUM_Tx,UDP6CSUM_Rx,UDP6CSUM_Tx,TSO6>
         enabled=0
         ec_capabilities=17<VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU,EEE>
         ec_enabled=2<VLAN_HWTAGGING>
         address: 3c:97:0e:4e:db:de
         media: Ethernet none (none)
         inet 192.168.88.252/24 broadcast 192.168.88.255 flags 0x0
         inet6 fe80::3e97:eff:fe4e:dbde%wm0/64 flags 0x0 scopeid 0x1
 
 The reason I add '192.168.88.2 192.168.88.1' route is so that a tap interface (behind 192.168.88.252 which is acting as hypervisor) from network '192.168.50.0/30' can reach '192.168.88.2'
 
 # commands before hang
 
 dc# route delete 192.168.88.2 192.168.88.1
 delete host 192.168.88.2: gateway 192.168.88.1
 dc# route add 192.168.88.2 192.168.88.1
 add host 192.168.88.2: gateway 192.168.88.1
 dc# fping -l -A 192.168.88.2
 192.168.88.2 : [0], 84 bytes, 0.76 ms (0.76 avg, 0% loss)
 ICMP Redirect from  for ICMP Echo sent to 192.168.88.2
 ##### it does not happen always, usually happens when route is active for more than 10 minutes.
 dc# route delete 192.168.88.2 192.168.88.2
 delete host 192.168.88.2: gateway 192.168.88.2
 dc# route add 192.168.88.2 192.168.88.1
 add host 192.168.88.2: gateway 192.168.88.1
 dc# fping -l -A 192.168.88.2
 192.168.88.2 : [0], 84 bytes, 0.76 ms (0.76 avg, 0% loss)
 ICMP Redirect from  for ICMP Echo sent to 192.168.88.2
 dc# route -n show | grep 192.168.88
 default            192.168.88.2       UG          -        -      -  wm0
 192.168.88/24      link#1             U           -        -      -  wm0
 192.168.88.2       192.168.88.2       UGH         -        -      -  wm0
 192.168.88.252     link#1             UHl         -        -      -  lo0
 192.168.88.1       b8:69:f4:db:8d:07  UH          -        -      -  wm0
 192.168.88.2       4c:5e:0c:b7:7e:08  UH          -        -      -  wm0
 ##### away for lunch
 dc# route delete 192.168.88.2 192.168.88.2
 <HANG>
 
 System starts acting up: typed keys shown with delay or not shown at all, network connections are dead, network related commands hang, at random times typing starts working normally then breaks again, trying to attach gdb to hanging route
 process also hangs.
 
 Finally, change virtual console or kill X to crash or freeze system.
 
 It takes multiple tries to reproduce. I was able to reproduce it 10+ times. With KASLR kernel it either hangs when trying to change virtual console or kill X, at other times it crashes kernel after killing X. A couple of times received a backtrace that stops at ':breakpoint'. With GENERIC (non-KASLR) kernel it freezes immediately and requires a hard reset.
 
 Thanks for your time, will look further into this.