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Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable

===============================
[ INFO: suspicious RCU usage. ]
SELinux:  policydb magic number 0xef03ff8c does not match expected magic number 0xf97cff8c
Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable
4.9.123-g520d10d3 #81 Not tainted
-------------------------------
kernel/rcu/tree_plugin.h:678 Illegal synchronize_rcu() in RCU read-side critical section!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 0
4 locks held by blkid/12703:
 #0:  (&mm->mmap_sem){++++++}, at: [<ffffffff810dcabb>] __do_page_fault+0x36b/0xd50 arch/x86/mm/fault.c:1337
 #1:  (rcu_read_lock){......}, at: [<ffffffff81439bda>] filemap_map_pages+0xfa/0xd40 mm/filemap.c:2242
 #2:  (&(ptlock_ptr(page))->rlock#2){+.+...}, at: [<ffffffff814ce5f3>] spin_lock include/linux/spinlock.h:302 [inline]
 #2:  (&(ptlock_ptr(page))->rlock#2){+.+...}, at: [<ffffffff814ce5f3>] pte_alloc_one_map mm/memory.c:2921 [inline]
 #2:  (&(ptlock_ptr(page))->rlock#2){+.+...}, at: [<ffffffff814ce5f3>] alloc_set_pte+0xb13/0x1290 mm/memory.c:3019
 #3:  (rcu_callback){......}, at: [<ffffffff81289b8e>] __rcu_reclaim kernel/rcu/rcu.h:108 [inline]
 #3:  (rcu_callback){......}, at: [<ffffffff81289b8e>] rcu_do_batch kernel/rcu/tree.c:2789 [inline]
 #3:  (rcu_callback){......}, at: [<ffffffff81289b8e>] invoke_rcu_callbacks kernel/rcu/tree.c:3053 [inline]
 #3:  (rcu_callback){......}, at: [<ffffffff81289b8e>] __rcu_process_callbacks kernel/rcu/tree.c:3020 [inline]
 #3:  (rcu_callback){......}, at: [<ffffffff81289b8e>] rcu_process_callbacks+0x98e/0x12b0 kernel/rcu/tree.c:3037

stack backtrace:
CPU: 1 PID: 12703 Comm: blkid Not tainted 4.9.123-g520d10d3 #81
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801db307d60 ffffffff81eb9689 ffff8801a12d9800 0000000000000000
 0000000000000002 ffffffff83c6e380 ffff8801c9927558 ffff8801db307d90
 ffffffff81428611 ffff8801c9927400 ffff8801a5fb4c48 ffff8801a5fb4448
Call Trace:
 <IRQ> [  154.753745]  [<ffffffff81eb9689>] __dump_stack lib/dump_stack.c:15 [inline]
 <IRQ> [  154.753745]  [<ffffffff81eb9689>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81428611>] lockdep_rcu_suspicious.cold.48+0x110/0x141 kernel/locking/lockdep.c:4455
 [<ffffffff81286428>] synchronize_rcu+0x68/0x90 kernel/rcu/tree_plugin.h:675
 [<ffffffff836c4f2a>] __l2tp_session_unhash+0x38a/0x520 net/l2tp/l2tp_core.c:1796
SELinux:  policydb magic number 0xef03ff8c does not match expected magic number 0xf97cff8c
 [<ffffffff836c52b7>] l2tp_tunnel_closeall+0x1f7/0x350 net/l2tp/l2tp_core.c:1364
 [<ffffffff836c5b72>] l2tp_tunnel_destruct+0x2f2/0x590 net/l2tp/l2tp_core.c:1324
 [<ffffffff830281f5>] __sk_destruct+0x55/0x590 net/core/sock.c:1428
 [<ffffffff81289aae>] __rcu_reclaim kernel/rcu/rcu.h:118 [inline]
 [<ffffffff81289aae>] rcu_do_batch kernel/rcu/tree.c:2789 [inline]
 [<ffffffff81289aae>] invoke_rcu_callbacks kernel/rcu/tree.c:3053 [inline]
 [<ffffffff81289aae>] __rcu_process_callbacks kernel/rcu/tree.c:3020 [inline]
 [<ffffffff81289aae>] rcu_process_callbacks+0x8ae/0x12b0 kernel/rcu/tree.c:3037
 [<ffffffff83a08980>] __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
 [<ffffffff83a07561>] exiting_irq arch/x86/include/asm/apic.h:669 [inline]
 [<ffffffff83a07561>] smp_apic_timer_interrupt+0x81/0xa0 arch/x86/kernel/apic/apic.c:962
 [<ffffffff83a036f0>] apic_timer_interrupt+0xa0/0xb0 arch/x86/entry/entry_64.S:648
 <EOI> [  154.877193]  [<ffffffff81222d25>] ? __read_once_size include/linux/compiler.h:243 [inline]
 <EOI> [  154.877193]  [<ffffffff81222d25>] ? list_empty include/linux/list.h:189 [inline]
 <EOI> [  154.877193]  [<ffffffff81222d25>] ? waitqueue_active include/linux/wait.h:137 [inline]
 <EOI> [  154.877193]  [<ffffffff81222d25>] ? __wake_up_bit+0x85/0xe0 kernel/sched/wait.c:455
 [<ffffffff81437ddb>] wake_up_page include/linux/pagemap.h:512 [inline]
 [<ffffffff81437ddb>] unlock_page+0xab/0x110 mm/filemap.c:865
 [<ffffffff8143a4c6>] filemap_map_pages+0x9e6/0xd40 mm/filemap.c:2303
 [<ffffffff814d4094>] do_fault_around mm/memory.c:3144 [inline]
 [<ffffffff814d4094>] do_read_fault mm/memory.c:3184 [inline]
 [<ffffffff814d4094>] do_fault mm/memory.c:3324 [inline]
 [<ffffffff814d4094>] handle_pte_fault mm/memory.c:3525 [inline]
 [<ffffffff814d4094>] __handle_mm_fault mm/memory.c:3612 [inline]
 [<ffffffff814d4094>] handle_mm_fault+0x1db4/0x2a00 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
 [<ffffffff83a02f08>] page_fault+0x28/0x30 arch/x86/entry/entry_64.S:951
ODEBUG: object ffff8801db307ce8 is NOT on stack ffff8801d4828000, but annotated
------------[ cut here ]------------
WARNING: CPU: 1 PID: 12703 at lib/debugobjects.c:303 debug_object_is_on_stack lib/debugobjects.c:303 [inline]
WARNING: CPU: 1 PID: 12703 at lib/debugobjects.c:303 __debug_object_init.cold.10+0x6b/0x2b0 lib/debugobjects.c:329