Re: IPsec traffic causes system to halt with 'kernel: double fault trap, code=0' at 'pf_setup_pdesc+0x3f'

[Alexander Bluhm]

On Fri, Jan 31, 2020 at 03:21:00PM +0000, Peter M??ller wrote:
>       tcp_output(ffff800000584ee0) at tcp_output+0x1941
>       tcp_output(ffff800000584ee0) at tcp_output+0x1941
>       tcp_output(ffff800000584ee0) at tcp_output+0x1941

Looks like stack exhaustion.  tcp_output() calls tcp_mtudisc() calls
tcp_output().

/usr/src/sys/netinet/tcp_output.c:1084

                if (error == EMSGSIZE) {
                        /*
                         * ip_output() will have already fixed the route
                         * for us.  tcp_mtudisc() will, as its last action,
                         * initiate retransmission, so it is important to
                         * not do so here.
                         */
                        tcp_mtudisc(tp->t_inpcb, -1);
                        return (0);
                }

bluhm