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ODEBUG: free active (active state 0) object type: work_struct hint: p9_read_work+0x0/0x1060 net/9p/trans_fd.c:208
WARNING: CPU: 1 PID: 4462 at lib/debugobjects.c:329 debug_print_object+0x16a/0x210 lib/debugobjects.c:326
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 4462 Comm: syz-executor156 Not tainted 4.18.0-rc4-next-20180710+ #3
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113
 panic+0x238/0x4e7 kernel/panic.c:184
 __warn.cold.8+0x163/0x1ba kernel/panic.c:536
 report_bug+0x252/0x2d0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 do_error_trap+0x1fc/0x4d0 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:996
RIP: 0010:debug_print_object+0x16a/0x210 lib/debugobjects.c:326
Code: 1a 88 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 92 00 00 00 48 8b 14 dd 20 92 1a 88 4c 89 f6 48 c7 c7 c0 87 1a 88 e8 56 2e e3 fd <0f> 0b 83 05 19 6c 3b 06 01 48 83 c4 18 5b 41 5c 41 5d 41 5e 41 5f 
RSP: 0018:ffff8801b84ef388 EFLAGS: 00010082
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff81634451 RDI: 0000000000000001
RBP: ffff8801b84ef3c8 R08: ffff8801abe983c0 R09: ffffed003b5e3ec2
R10: ffffed003b5e3ec2 R11: ffff8801daf1f617 R12: 0000000000000001
R13: ffffffff88f63c00 R14: ffffffff881a8c60 R15: ffffffff814ec5a0
 __debug_check_no_obj_freed lib/debugobjects.c:783 [inline]
 debug_check_no_obj_freed+0x3b2/0x595 lib/debugobjects.c:815
 kfree+0xc7/0x260 mm/slab.c:3812
 p9_fd_close+0x416/0x5b0 net/9p/trans_fd.c:893
 p9_client_create+0xac2/0x16c9 net/9p/client.c:1076
 v9fs_session_init+0x21a/0x1a80 fs/9p/v9fs.c:400
 v9fs_mount+0x7c/0x900 fs/9p/vfs_super.c:135
 legacy_get_tree+0x118/0x440 fs/fs_context.c:659
 vfs_get_tree+0x1cb/0x5c0 fs/super.c:1743
 do_new_mount fs/namespace.c:2567 [inline]
 do_mount+0x6c1/0x1fb0 fs/namespace.c:2889
 ksys_mount+0x12d/0x140 fs/namespace.c:3105
 __do_sys_mount fs/namespace.c:3119 [inline]
 __se_sys_mount fs/namespace.c:3116 [inline]
 __x64_sys_mount+0xbe/0x150 fs/namespace.c:3116
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x445669
Code: e8 ec b9 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 8b 12 fc ff c3 66 2e 0f 1f 84 00 00 00 00 
RSP: 002b:00007f51ca812d18 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00000000006dac24 RCX: 0000000000445669
RDX: 0000000020000100 RSI: 00000000200000c0 RDI: 0000000000000000
RBP: 00000000006dac20 R08: 0000000020000480 R09: 65732f636f72702f
R10: 0000000000000000 R11: 0000000000000206 R12: 00007f51ca812d20
R13: 0030656c69662f2e R14: 666e69746e756f6d R15: 0000000000000001
Shutting down cpus with NMI
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..