PID: 21223  TASK: ffff8800adc50000  CPU: 0   COMMAND: "umount"
 #0 [ffff8800a9acba58] machine_kexec at ffffffff810613ae
    /home/green/bk/linux-3.10.0-1160.59.1.el7-debug/arch/x86/kernel/machine_kexec_64.c: 343
 #1 [ffff8800a9acbab8] __crash_kexec at ffffffff811160a2
    /home/green/bk/linux-3.10.0-1160.59.1.el7-debug/kernel/kexec_core.c: 897
 #2 [ffff8800a9acbb88] panic at ffffffff817d8546
    /home/green/bk/linux-3.10.0-1160.59.1.el7-debug/./arch/x86/include/asm/smp.h: 93
 #3 [ffff8800a9acbc08] lbug_with_loc at ffffffffa02abae5 [libcfs]
    /home/green/git/lustre-release/libcfs/libcfs/debug.c: 466
 #4 [ffff8800a9acbc20] lu_device_fini at ffffffffa058e698 [obdclass]
    /home/green/git/lustre-release/lustre/obdclass/lu_object.c: 1249
 #5 [ffff8800a9acbc30] lovsub_device_free at ffffffffa0ac8734 [lov]
    /home/green/git/lustre-release/lustre/include/obd_support.h: 806
 #6 [ffff8800a9acbc50] lu_stack_fini at ffffffffa0594d11 [obdclass]
    /home/green/git/lustre-release/lustre/obdclass/lu_object.c: 1381
 #7 [ffff8800a9acbc88] cl_stack_fini at ffffffffa059a96e [obdclass]
    /home/green/git/lustre-release/lustre/obdclass/cl_object.c: 1051
 #8 [ffff8800a9acbc98] lov_device_fini at ffffffffa0aa106c [lov]
 #9 [ffff8800a9acbcc8] lu_stack_fini at ffffffffa0594cd5 [obdclass]
    /home/green/git/lustre-release/lustre/obdclass/lu_object.c: 1375
#10 [ffff8800a9acbd00] cl_stack_fini at ffffffffa059a96e [obdclass]
    /home/green/git/lustre-release/lustre/obdclass/cl_object.c: 1051
#11 [ffff8800a9acbd10] cl_sb_fini at ffffffffa102b7c0 [lustre]
    /home/green/git/lustre-release/lustre/llite/vvp_dev.c: 354
#12 [ffff8800a9acbd40] ll_put_super at ffffffffa0feb088 [lustre]
    /home/green/git/lustre-release/lustre/llite/llite_lib.c: 958
#13 [ffff8800a9acbe40] generic_shutdown_super at ffffffff812476ca
    /home/green/bk/linux-3.10.0-1160.59.1.el7-debug/fs/super.c: 401
#14 [ffff8800a9acbe60] kill_anon_super at ffffffff81247ac2
    /home/green/bk/linux-3.10.0-1160.59.1.el7-debug/fs/super.c: 961
#15 [ffff8800a9acbe78] lustre_kill_super at ffffffffa101bdbb [lustre]
    /home/green/git/lustre-release/lustre/llite/super25.c: 213
#16 [ffff8800a9acbe90] deactivate_locked_super at ffffffff81247ec9
    /home/green/bk/linux-3.10.0-1160.59.1.el7-debug/fs/super.c: 277
#17 [ffff8800a9acbeb0] deactivate_super at ffffffff81248616
    /home/green/bk/linux-3.10.0-1160.59.1.el7-debug/fs/super.c: 298
#18 [ffff8800a9acbec8] cleanup_mnt at ffffffff81268b1f
    /home/green/bk/linux-3.10.0-1160.59.1.el7-debug/fs/namespace.c: 1172
#19 [ffff8800a9acbee0] __cleanup_mnt at ffffffff81268bb2
    /home/green/bk/linux-3.10.0-1160.59.1.el7-debug/fs/namespace.c: 1179
#20 [ffff8800a9acbef0] task_work_run at ffffffff810b69b5
    /home/green/bk/linux-3.10.0-1160.59.1.el7-debug/kernel/task_work.c: 89
#21 [ffff8800a9acbf30] do_notify_resume at ffffffff8102ccb2
    /home/green/bk/linux-3.10.0-1160.59.1.el7-debug/include/linux/tracehook.h: 196
#22 [ffff8800a9acbf50] int_signal at ffffffff817f4363
    /home/green/bk/linux-3.10.0-1160.59.1.el7-debug/arch/x86/kernel/entry_64.S: 701
    RIP: 00007f5af747dba7  RSP: 00007ffed0e26dd8  RFLAGS: 00000246
    RAX: 0000000000000000  RBX: 000055d0b20c3040  RCX: ffffffffffffffff
    RDX: 0000000000000001  RSI: 0000000000000000  RDI: 000055d0b20c8a60
    RBP: 000055d0b20c8a60   R8: 0000000000000000   R9: 000000000000000c
    R10: 00007ffed0e26860  R11: 0000000000000246  R12: 00007f5af7ffbd78
    R13: 0000000000000000  R14: 000055d0b20c7830  R15: 000055d0b20c3040
    ORIG_RAX: 00000000000000a6  CS: 0033  SS: 002b