Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable
INFO: trying to register non-static key.
the code is fine but needs lockdep annotation.
turning off the locking correctness validator.
CPU: 0 PID: 18084 Comm: loop0 Not tainted 4.15.0-rc3-next-20171214+ #67
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xe9/0x14b lib/dump_stack.c:53
 register_lock_class+0x164/0x5d0 kernel/locking/lockdep.c:752
 __lock_acquire+0xb4/0x1430 kernel/locking/lockdep.c:3314
 lock_acquire+0xbf/0x220 kernel/locking/lockdep.c:3914
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x56/0x70 kernel/locking/spinlock.c:152
 __wake_up_common_lock+0x51/0x90 kernel/sched/wait.c:124
 __wake_up+0xe/0x10 kernel/sched/wait.c:149
 sbq_wake_up lib/sbitmap.c:465 [inline]
 sbitmap_queue_clear+0x154/0x160 lib/sbitmap.c:473
 blk_mq_put_tag+0x47/0x90 block/blk-mq-tag.c:191
 blk_mq_free_request+0x1b5/0x260 block/blk-mq.c:489
 __blk_mq_end_request block/blk-mq.c:507 [inline]
 blk_mq_end_request+0x5d/0xb0 block/blk-mq.c:516
 lo_complete_rq+0x43/0xa0 drivers/block/loop.c:463
 __blk_mq_complete_request+0x118/0x1c0 block/blk-mq.c:555
 blk_mq_complete_request+0x34/0x40 block/blk-mq.c:575
 loop_handle_cmd drivers/block/loop.c:1723 [inline]
 loop_queue_work+0x6c/0xcc0 drivers/block/loop.c:1732
 kthread_worker_fn+0xe0/0x290 kernel/kthread.c:642
 loop_kthread_worker_fn+0x25/0x30 drivers/block/loop.c:841
 kthread+0x149/0x170 kernel/kthread.c:238
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:524
BUG: unable to handle kernel NULL pointer dereference at           (null)
IP: __wake_up_common+0x49/0x150 kernel/sched/wait.c:87
PGD 1df7b2067 P4D 1df7b2067 PUD 1df7b3067 PMD 0 
Oops: 0000 [#1] SMP
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 18084 Comm: loop0 Not tainted 4.15.0-rc3-next-20171214+ #67
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__wake_up_common+0x49/0x150 kernel/sched/wait.c:87
RSP: 0018:ffffc90000db7bb0 EFLAGS: 00010082
RAX: 0000000000000000 RBX: ffff8801dc4bc808 RCX: 0000000000000000
RDX: 0000000000000001 RSI: 0000000000000003 RDI: ffff8801dc4bc808
RBP: ffffc90000db7bf8 R08: ffffffffffffffe8 R09: ffffc90000db7c10
R10: ffffc90000db7b70 R11: 0000000000000000 R12: ffff8801dc4bc840
R13: ffffc90000db7c10 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88021fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000001d92a1000 CR4: 00000000001406f0
DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 __wake_up_common_lock+0x6c/0x90 kernel/sched/wait.c:125
 __wake_up+0xe/0x10 kernel/sched/wait.c:149
 sbq_wake_up lib/sbitmap.c:465 [inline]
 sbitmap_queue_clear+0x154/0x160 lib/sbitmap.c:473
 blk_mq_put_tag+0x47/0x90 block/blk-mq-tag.c:191
 blk_mq_free_request+0x1b5/0x260 block/blk-mq.c:489
 __blk_mq_end_request block/blk-mq.c:507 [inline]
 blk_mq_end_request+0x5d/0xb0 block/blk-mq.c:516
 lo_complete_rq+0x43/0xa0 drivers/block/loop.c:463
 __blk_mq_complete_request+0x118/0x1c0 block/blk-mq.c:555
 blk_mq_complete_request+0x34/0x40 block/blk-mq.c:575
 loop_handle_cmd drivers/block/loop.c:1723 [inline]
 loop_queue_work+0x6c/0xcc0 drivers/block/loop.c:1732
 kthread_worker_fn+0xe0/0x290 kernel/kthread.c:642
 loop_kthread_worker_fn+0x25/0x30 drivers/block/loop.c:841
 kthread+0x149/0x170 kernel/kthread.c:238
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:524
Code: 4d d0 4c 89 45 c8 74 0a 41 f6 01 04 0f 85 8d 00 00 00 49 8b 44 24 38 4c 8d 40 e8 49 8d 40 18 49 83 c4 38 89 55 c0 49 39 c4 74 4c <49> 8b 40 18 31 db 4c 8d 78 e8 45 8b 30 41 f6 c6 04 75 4b 48 8b 
RIP: __wake_up_common+0x49/0x150 kernel/sched/wait.c:87 RSP: ffffc90000db7bb0
CR2: 0000000000000000
---[ end trace cdabda5476a60604 ]---