Comment 1 Kristof Provost 2018-11-29 08:26:49 UTC

Can you describe your setup? It looks like you might have a vlan interface involved somewhere, but knowing how it's all set up will likely make reproducing this easier.

Yes, I can go into some more detail about the networking.

On the host system, only igb1 is currently active.  It is a trunk interface, so on the host I have igb1.1 configured.

I am utilizing Devin Teske's jng to create a netgraph bridge to igb1, exposing the trunked interface to the jail.  This jail only needs 1 VLAN, but I anticipate adding others later that will utilize more, and this seemed more elegant than cloning the VLAN interfaces individually.

In the jail, I am replicate the same setup as the host to access the tagged interface.

host rc.conf:
=============================
ifconfig_igb1="up"
vlans_igb1="1"
ifconfig_igb1_1="192.168.1.2 netmask 255.255.255.0"
=============================


jail rc.conf:
=============================
vlans_ng0_unifi="1"
ifconfig_ng0_unifi="up"
ifconfig_ng0_unifi_1="inet 192.168.1.3 netmask 255.255.255.0"
=============================


For this particular jail the configuration is overkill (I suppose I could just bridge to igb1.1 on the host).  But I am proving out this strategy for some of the other services that I will need to host on this machine later.  Otherwise, I will have to go back to the strategy of mangling multiple FIBs.

Comment 3 Bjoern A. Zeeb 2018-11-29 11:33:29 UTC

I can probably have a quick look this evening unless anyone beats me to it.
Looking at the backtrace I have a suspicion of what's going on.

Hi Bjoern & Kristof,

I wanted to provide some additional information that I have gathered today.  I have upgraded this system to 12.0-RC3 and can confirm the issue remains.  I also believe it is related to the netgraph module.  I have converted a jail to use jib and mod if_bridge/if_epair.  I can now stop the jail without experiencing the kernel panic.

I hope this helps confirm or direct your suspicions.  Let me know if I can do any additional tests.  I will look into it further when I can, but it may be some time before I can do so, and it is entirely possible that the networking code exceeds my skill in C.

Best,

Jordan

Comment 5 Bjoern A. Zeeb 2019-01-15 23:20:05 UTC

Sorry, I got side-tracked while I was looking at this.  Release it to net@ in case someone else beats me to fixing it.

Comment 6 Eugene Grosbein 2019-01-16 09:11:45 UTC

This PR lack many valuable technical details. If the problem is really in netgraph, please you describe used nodes and their hooks and settings because just notice of some "jng" (whatever it is) not enough. Plain ng0 is p2p-interface and vlan is not. You should also supply any additional details that may be relevand and do not forget to show output of "ngctl list" when jail is up and running, before is panices kernel at shutdown.

I can reproduce this panic with 12.0-RELEASE-p7 r350232 and a pretty forward out-of-the-handbook Jail setup.

This should be enough to get a nasty panic:

Host:
/etc/rc.conf:
[...]
vlans_em0="vlcx0"
create_args_vlcx0="vlan 18"
ifconfig_em0="up"
ifconfig_vlcx0="inet 10.8.8.110 netmask 255.255.255.0"
[...]
jail_enable="YES"
jail_confwarn="YES"
jail_parallel_start="NO"
jail_list="jv"
jail_reverse_stop="YES"

---------------------------------------------------------------------

/etc/jail.conf:
exec.start = "/bin/sh /etc/rc";
exec.stop = "/bin/sh /etc/rc.shutdown";
exec.clean;

jv {
        host.hostname = "julesverne.stk.cx";
        path = "/var/local/prison/jv";
        exec.clean;
        exec.system_user = "root";
        exec.jail_user = "root";
        vnet;
        exec.clean;
        vnet.interface = "ng0_jv";
        exec.system_user = "root";
        exec.jail_user = "root";
        exec.prestart += "/l/om/sbin/jng bridge jv em0";
        exec.poststop += "/l/om/sbin/jng shutdown jv";

        # Standard stuff
        exec.consolelog = "/var/local/log/jails/jv_console.log";
        mount.devfs;          #mount devfs
        allow.raw_sockets;    #allow ping-pong
        devfs_ruleset="5";    #devfs ruleset for this jail
        mount.devfs;
}

--------------------------------------------------------------------

Jail /etc/rc.conf:
[...]
ifconfig_ng0_jv="up"
vlans_ng0_jv="jjvcx0"
create_args_jjvcx0="vlan 18"
ifconfig_jjvcx0="inet 10.8.8.190 netmask 255.255.255.0"
[...]


/l/om/sbin/jng is a copy of /usr/src/share/examples/jails/jng

This should be everything you need to get exact the panic described in this bug report.