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WARNING: CPU: 0 PID: 0 at fs/ext4/page-io.c:205 ext4_add_complete_io fs/ext4/page-io.c:205 [inline]
WARNING: CPU: 0 PID: 0 at fs/ext4/page-io.c:205 ext4_put_io_end_defer+0x2bb/0x3b0 fs/ext4/page-io.c:268
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.9.133+ #52
 ffff8801db607a48 ffffffff81b37069 ffffffff82a38ba0 00000000ffffffff
 0000000000000000 0000000000000000 00000000000000cd ffff8801db607b08
 ffffffff813f6a45 0000000041b58ab3 ffffffff82e299a3 ffffffff813f6886
Call Trace:
 <IRQ> [  193.600245]  [<ffffffff81b37069>] __dump_stack lib/dump_stack.c:15 [inline]
 <IRQ> [  193.600245]  [<ffffffff81b37069>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff813f6a45>] panic+0x1bf/0x39f kernel/panic.c:179
 [<ffffffff813f6d14>] __warn.cold.9+0xc1/0x17f kernel/panic.c:542
 [<ffffffff810dbe2c>] warn_slowpath_null+0x2c/0x40 kernel/panic.c:585
 [<ffffffff816e8cfb>] ext4_add_complete_io fs/ext4/page-io.c:205 [inline]
 [<ffffffff816e8cfb>] ext4_put_io_end_defer+0x2bb/0x3b0 fs/ext4/page-io.c:268
 [<ffffffff816e8f26>] ext4_end_bio+0x136/0x460 fs/ext4/page-io.c:324
 [<ffffffff81aaa165>] bio_endio+0x1a5/0x1f0 block/bio.c:1781
 [<ffffffff81aca7c8>] req_bio_endio block/blk-core.c:157 [inline]
 [<ffffffff81aca7c8>] blk_update_request+0x248/0x9b0 block/blk-core.c:2628
 [<ffffffff81e107bd>] scsi_end_request+0x9d/0x5c0 drivers/scsi/scsi_lib.c:606
 [<ffffffff81e197c3>] scsi_io_completion+0x273/0x17a0 drivers/scsi/scsi_lib.c:829
 [<ffffffff81dfc6ea>] scsi_finish_command+0x3ba/0x530 drivers/scsi/scsi.c:607
 [<ffffffff81e17cf0>] scsi_softirq_done+0x250/0x360 drivers/scsi/scsi_lib.c:1567
 [<ffffffff81ae868d>] blk_done_softirq+0x27d/0x3e0 block/blk-softirq.c:35
 [<ffffffff82808d00>] __do_softirq+0x210/0x940 kernel/softirq.c:288
 [<ffffffff810efb24>] invoke_softirq kernel/softirq.c:368 [inline]
 [<ffffffff810efb24>] irq_exit+0x114/0x150 kernel/softirq.c:409
 [<ffffffff82805d1d>] exiting_irq arch/x86/include/asm/apic.h:669 [inline]
 [<ffffffff82805d1d>] do_IRQ+0x10d/0x1c0 arch/x86/kernel/irq.c:252
 [<ffffffff8280431d>] common_interrupt+0x9d/0x9d arch/x86/entry/entry_64.S:461
 <EOI> [  193.788337]  [<ffffffff82802626>] ? native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:56
 [<ffffffff82801b85>] arch_safe_halt arch/x86/include/asm/paravirt.h:104 [inline]
 [<ffffffff82801b85>] default_idle+0x55/0x360 arch/x86/kernel/process.c:437
 [<ffffffff810689d0>] arch_cpu_idle+0x10/0x20 arch/x86/kernel/process.c:428
 [<ffffffff82802a85>] default_idle_call+0x45/0x60 kernel/sched/idle.c:97
 [<ffffffff811f0745>] cpuidle_idle_call kernel/sched/idle.c:155 [inline]
 [<ffffffff811f0745>] cpu_idle_loop kernel/sched/idle.c:248 [inline]
 [<ffffffff811f0745>] cpu_startup_entry+0x2b5/0x380 kernel/sched/idle.c:303
 [<ffffffff827f107c>] rest_init+0x183/0x189 init/main.c:409
 [<ffffffff8341a91b>] start_kernel+0x5fb/0x62f init/main.c:664
 [<ffffffff8341929a>] x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:196
 [<ffffffff834193d6>] x86_64_start_kernel+0x13a/0x15d arch/x86/kernel/head64.c:177
Kernel Offset: disabled
Rebooting in 86400 seconds..