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WARNING: CPU: 0 PID: 8131 at net/batman-adv/multicast.c:337 batadv_mcast_mla_tt_retract+0x309/0x3d0 net/batman-adv/multicast.c:337
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 8131 Comm: kworker/u4:1 Not tainted 4.19.40 #8
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_mcast_mla_update
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 panic+0x263/0x51d kernel/panic.c:185
 __warn.cold+0x20/0x54 kernel/panic.c:540
 report_bug+0x263/0x2b0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 fixup_bug arch/x86/kernel/traps.c:173 [inline]
 do_error_trap+0x204/0x360 arch/x86/kernel/traps.c:296
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:997
RIP: 0010:batadv_mcast_mla_tt_retract+0x309/0x3d0 net/batman-adv/multicast.c:337
Code: 1d 8a 96 fa 4c 8b 7d c0 4d 85 ff 0f 85 c3 fd ff ff e8 0b 8a 96 fa 48 83 c4 38 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 f7 89 96 fa <0f> 0b e9 54 fd ff ff e8 3b 00 cd fa e9 37 fe ff ff 48 89 df e8 4e
RSP: 0018:ffff88808a267b50 EFLAGS: 00010293
RAX: ffff888089de24c0 RBX: 0000000000000001 RCX: ffffffff86d4f3fb
RDX: 0000000000000000 RSI: ffffffff86d4f6a9 RDI: 0000000000000007
RBP: ffff88808a267bb0 R08: ffff888089de24c0 R09: 0000000000000002
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88808a267c98
R13: ffff888048294b90 R14: 0000000000000000 R15: ffff88808a267d08
 __batadv_mcast_mla_update net/batman-adv/multicast.c:635 [inline]
 batadv_mcast_mla_update+0x553/0x1ec0 net/batman-adv/multicast.c:661
 process_one_work+0x98e/0x1760 kernel/workqueue.c:2153
 worker_thread+0x98/0xe40 kernel/workqueue.c:2296
 kthread+0x357/0x430 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413
Kernel Offset: disabled
Rebooting in 86400 seconds..