This seems to be a NULL pointer exception caused by tunnel->sock being NULL at the call to bh_lock_sock() in l2tp_xmit_skb() at l2tp_core.c:1135.
tunnel->sock is set NULL in l2tp_core's tunnel socket destructor. At the moment, I don't understand how this happens because pppol2tp_xmit() does a sock_hold() on the tunnel socket before l2tp_xmit_skb() is called. I'm still looking at this. Has this problem only recently started happening? On 1 October 2017 at 18:21, Stephen Hemminger <step...@networkplumber.org> wrote: > > > Begin forwarded message: > > Date: Sun, 01 Oct 2017 16:22:33 +0000 > From: bugzilla-dae...@bugzilla.kernel.org > To: step...@networkplumber.org > Subject: [Bug 197099] New: Kernel panic in interrupt [l2tp_ppp] > > > https://bugzilla.kernel.org/show_bug.cgi?id=197099 > > Bug ID: 197099 > Summary: Kernel panic in interrupt [l2tp_ppp] > Product: Networking > Version: 2.5 > Kernel Version: 4.8.13-1.el6.elrepo.x86_64 > Hardware: x86-64 > OS: Linux > Tree: Mainline > Status: NEW > Severity: normal > Priority: P1 > Component: Other > Assignee: step...@networkplumber.org > Reporter: svi...@gmail.com > Regression: No > > Created attachment 258685 > --> https://bugzilla.kernel.org/attachment.cgi?id=258685&action=edit > stacktrace screenshot > > Hello! > > Getting kernel panics on multiple servers. Since it mentions l2tp_core, > l2tp_ppp and ppp_generic, I decided to report it to Networking (correct me if > I'm wrong). > > Unfortunately I'm still struggling with making kdump work, so the trace > screenshot is all I have at this moment. The only hope is that this stacktrace > means something to the guys that wrote the code. > > -- > You are receiving this mail because: > You are the assignee for the bug.