syzbot

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WARNING: CPU: 0 PID: 3805 at kernel/locking/mutex.c:873 __mutex_trylock_slowpath kernel/locking/mutex.c:873 [inline]
WARNING: CPU: 0 PID: 3805 at kernel/locking/mutex.c:873 mutex_trylock+0x2f9/0x3e0 kernel/locking/mutex.c:908
DEBUG_LOCKS_WARN_ON(in_interrupt())[  144.028993] Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 3805 Comm: syz-executor2 Not tainted 4.9.124-g09eb2ba #83
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801db2077f8 ffffffff81eb95e9 ffffffff83c48ac0 00000000ffffffff
 0000000000000000 0000000000000000 0000000000000369 ffff8801db2078b8
 ffffffff81423eb5 0000000041b58ab3 ffffffff843bb8e8 ffffffff81423cf6
Call Trace:
 <IRQ> [  144.082024]  [<ffffffff81eb95e9>] __dump_stack lib/dump_stack.c:15 [inline]
 <IRQ> [  144.082024]  [<ffffffff81eb95e9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81423eb5>] panic+0x1bf/0x3bc kernel/panic.c:179
 [<ffffffff814241a1>] __warn.cold.9+0xc1/0x17f kernel/panic.c:542
 [<ffffffff81138252>] warn_slowpath_fmt+0xc2/0x100 kernel/panic.c:565
 [<ffffffff839f6af9>] __mutex_trylock_slowpath kernel/locking/mutex.c:873 [inline]
 [<ffffffff839f6af9>] mutex_trylock+0x2f9/0x3e0 kernel/locking/mutex.c:908
 [<ffffffff81284d69>] exp_funnel_lock kernel/rcu/tree_exp.h:256 [inline]
 [<ffffffff81284d69>] _synchronize_rcu_expedited+0x339/0x840 kernel/rcu/tree_exp.h:569
 [<ffffffff812862c3>] synchronize_rcu_expedited kernel/rcu/tree_exp.h:687 [inline]
 [<ffffffff812862c3>] synchronize_rcu.part.62+0xd3/0x110 kernel/rcu/tree_plugin.h:682
 [<ffffffff81286327>] synchronize_rcu+0x27/0x90 kernel/rcu/tree_plugin.h:685
 [<ffffffff836c4baa>] __l2tp_session_unhash+0x38a/0x520 net/l2tp/l2tp_core.c:1796
 [<ffffffff836c4f37>] l2tp_tunnel_closeall+0x1f7/0x350 net/l2tp/l2tp_core.c:1364
 [<ffffffff836c57f2>] l2tp_tunnel_destruct+0x2f2/0x590 net/l2tp/l2tp_core.c:1324
 [<ffffffff830281f5>] __sk_destruct+0x55/0x590 net/core/sock.c:1428
 [<ffffffff812899ee>] __rcu_reclaim kernel/rcu/rcu.h:118 [inline]
 [<ffffffff812899ee>] rcu_do_batch kernel/rcu/tree.c:2789 [inline]
 [<ffffffff812899ee>] invoke_rcu_callbacks kernel/rcu/tree.c:3053 [inline]
 [<ffffffff812899ee>] __rcu_process_callbacks kernel/rcu/tree.c:3020 [inline]
 [<ffffffff812899ee>] rcu_process_callbacks+0x8ae/0x12b0 kernel/rcu/tree.c:3037
 [<ffffffff83a085c0>] __do_softirq+0x210/0x940 kernel/softirq.c:288
 [<ffffffff8114d554>] invoke_softirq kernel/softirq.c:368 [inline]
 [<ffffffff8114d554>] irq_exit+0x114/0x150 kernel/softirq.c:409
 [<ffffffff83a071a1>] exiting_irq arch/x86/include/asm/apic.h:669 [inline]
 [<ffffffff83a071a1>] smp_apic_timer_interrupt+0x81/0xa0 arch/x86/kernel/apic/apic.c:962
 [<ffffffff83a03330>] apic_timer_interrupt+0xa0/0xb0 arch/x86/entry/entry_64.S:648
 <EOI> [  144.347469]  [<ffffffff81f21066>] ? check_preemption_disabled+0x36/0x170 lib/smp_processor_id.c:15
 [<ffffffff81f211dc>] __this_cpu_preempt_check+0x1c/0x20 lib/smp_processor_id.c:62
 [<ffffffff8149b700>] __mod_node_page_state+0x50/0xe0 mm/vmstat.c:268
 [<ffffffff814f5773>] page_add_new_anon_rmap+0x193/0x3a0 mm/rmap.c:1297
 [<ffffffff814c4ead>] wp_page_copy+0x8fd/0x1560 mm/memory.c:2216
 [<ffffffff814c7c32>] do_wp_page+0x252/0x1f70 mm/memory.c:2448
 [<ffffffff814d35d3>] handle_pte_fault mm/memory.c:3540 [inline]
 [<ffffffff814d35d3>] __handle_mm_fault mm/memory.c:3612 [inline]
 [<ffffffff814d35d3>] handle_mm_fault+0x13c3/0x2a00 mm/memory.c:3649
 [<ffffffff810dccff>] __do_page_fault+0x5af/0xd50 arch/x86/mm/fault.c:1408
 [<ffffffff810dd4c7>] do_page_fault+0x27/0x30 arch/x86/mm/fault.c:1471
 [<ffffffff83a02b48>] page_fault+0x28/0x30 arch/x86/entry/entry_64.S:951
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..