Was able to pull a little more this time. This help?

 datasource:      [   29.570013] ------------[ cut here ]------------
[   29.575937] kernel BUG at mm/slub.c:3601!
[   29.580741] invalid opcode: 0000 [#1] SMP
[   29.585663] Modules linked in: wireguard(OE) veth vxlan ip6_udp_tunnel
udp_tunnel bridge sd
[   29.689129] CPU: 1 PID: 223 Comm: kworker/1:1 Tainted: G           OE
------------   3.101
[   29.700019] Hardware name: Dell Inc. PowerEdge R640/0W23H8, BIOS 1.3.7
02/08/2018
[   29.708399] Workqueue: wg-crypt-wg0 packet_rx_worker [wireguard]
[   29.715340] task: ffff920e8b608000 ti: ffff920e8b610000 task.ti:
ffff920e8b610000
[   29.723722] RIP: 0010:[<ffffffff8b1f6c1c>]  [<ffffffff8b1f6c1c>]
kfree+0x13c/0x140
[   29.732222] RSP: 0018:ffff920e8b613ce8  EFLAGS: 00010246
[   29.738429] RAX: 006fffff00000000 RBX: ffff920e76fbf000 RCX:
00000000fffbdd13
[   29.746466] RDX: 006fffff00000000 RSI: 0000000000000206 RDI:
ffff920e76fbf000
[   29.754489] RBP: ffff920e8b613d00 R08: 0000000000000001 R09:
b7c55a3205f72200
[   29.762508] R10: 0000000000000000 R11: ffffeddddfdbefc0 R12:
ffff920e76fbf6c0
[   29.770525] R13: ffffffff8b5d60c5 R14: ffff920e80220000 R15:
ffff920e7e7e2500
[   29.778535] FS:  0000000000000000(0000) GS:ffff920e8be00000(0000)
knlGS:0000000000000000
[   29.787497] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   29.794125] CR2: 00007ffe415adee0 CR3: 0000000c0e1ea000 CR4:
00000000007607e0
[   29.802143] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
0000000000000000
[   29.810161] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7:
0000000000000400
[   29.818152] PKRU: 00000000
[   29.821713] Call Trace:
[   29.825002]  [<ffffffff8b5d60c5>] skb_release_data+0xf5/0x140
[   29.831595]  [<ffffffff8b5d6134>] skb_release_all+0x24/0x30
[   29.838008]  [<ffffffff8b5d659c>] consume_skb+0x2c/0x90
[   29.844073]  [<ffffffffc088df35>] packet_rx_worker+0x2d5/0x7f0
[wireguard]
[   29.851802]  [<ffffffff8b71291c>] ? __schedule+0x41c/0xa20
[   29.858139]  [<ffffffff8b0b2dff>] process_one_work+0x17f/0x440
[   29.864817]  [<ffffffff8b0b3ac6>] worker_thread+0x126/0x3c0
[   29.871238]  [<ffffffff8b0b39a0>] ? manage_workers.isra.24+0x2a0/0x2a0
[   29.878612]  [<ffffffff8b0bae31>] kthread+0xd1/0xe0
[   29.884338]  [<ffffffff8b0bad60>] ? insert_kthread_work+0x40/0x40
[   29.891284]  [<ffffffff8b71f61d>] ret_from_fork_nospec_begin+0x7/0x21
[   29.898578]  [<ffffffff8b0bad60>] ? insert_kthread_work+0x40/0x40
[   29.905513] Code: 49 8b 03 31 f6 f6 c4 40 74 04 41 8b 73 68 4c 89 df e8
89 63 fa ff eb 84
[   29.927746] RIP  [<ffffffff8b1f6c1c>] kfree+0x13c/0x140
[   29.933888]  RSP <ffff920e8b613ce8>
                [   29.938300] ---[ end trace 66811942e35f2cba ]---
                            #
[   29.948435] Kernel panic - not syncing: Fatal exception in interrupt


On Thu, May 10, 2018 at 1:26 PM Jason A. Donenfeld <Jason@zx2c4.com> wrote:

> Yikes. I guess I need to examine my compat backport closely. Do you
> have any more logging than that? Usually there's a backtrace.
>
-- 
Henry Snow | Director, Site Reliability Engineering
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