BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 IP: [] __lock_acquire+0x2b0/0x1c70 kernel/locking/lockdep.c:3093 PGD 205efd067 PUD 209cfc067 PMD 0 Oops: 0000 [#1] SMP Modules linked in: CPU: 1 PID: 20989 Comm: kworker/1:0 Not tainted 4.1.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events p9_poll_workfn task: ffff8800b9c58210 ti: ffff8802148e4000 task.ti: ffff8802148e4000 RIP: 0010:[] [] __lock_acquire+0x2b0/0x1c70 kernel/locking/lockdep.c:3093 RSP: 0018:ffff8802148e7b68 EFLAGS: 00010002 RAX: 0000000000000086 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: ffff8802148e7c28 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000018 R15: ffff8800b9c58210 FS: 0000000000000000(0000) GS:ffff88021fd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000018 CR3: 00000001fb391000 CR4: 00000000001407e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Stack: 0000000000000007 ffff8800b9c58210 0000000000000006 ffff8800b9c58a30 ffff8802148e7bc8 ffffffff00000001 0000000000000000 ffff880000000000 ffffffff822d1379 ffff88020f9ffc00 ffffffff82d94e60 0000000000000080 Call Trace: [] lock_acquire+0xe0/0x2f0 kernel/locking/lockdep.c:3623 [] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:112 [inline] [] _raw_spin_lock_irqsave+0x5f/0x90 kernel/locking/spinlock.c:159 [] p9_conn_cancel+0x2c/0x170 net/9p/trans_fd.c:205 [] p9_poll_mux net/9p/trans_fd.c:626 [inline] [] p9_poll_workfn+0x11e/0x160 net/9p/trans_fd.c:1093 [] process_one_work+0x20e/0x850 kernel/workqueue.c:2025 [] worker_thread+0x4b/0x470 kernel/workqueue.c:2157 [] kthread+0xea/0x100 drivers/block/aoe/aoecmd.c:1312 [] ret_from_fork+0x42/0x70 arch/x86/kernel/entry_64.S:639 Code: 31 c0 e8 0b 0e 10 01 e8 5c 40 10 01 0f 1f 80 00 00 00 00 31 db 48 81 c4 98 00 00 00 89 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 66 90 <49> 81 3e 00 03 fc 82 b8 00 00 00 00 44 0f 44 e0 41 83 fd 01 0f RIP [] __lock_acquire+0x2b0/0x1c70 kernel/locking/lockdep.c:3232 RSP CR2: 0000000000000018 ---[ end trace a1d00b9ba5dc74d8 ]---