FYI, we noticed the below changes on https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master commit 373ccbe5927034b55bdc80b0f8b54d6e13fe8d12 ("mm, vmstat: allow WQ concurrency to discover memory reclaim doesn't make any progress") +------------------------------------------+------------+------------+ | | 475a2f905d | 373ccbe592 | +------------------------------------------+------------+------------+ | boot_successes | 303 | 265 | | boot_failures | 0 | 39 | | BUG:unable_to_handle_kernel | 0 | 39 | | Oops | 0 | 39 | | EIP_is_at__queue_work | 0 | 39 | | Kernel_panic-not_syncing:Fatal_exception | 0 | 39 | | backtrace:vmstat_shepherd | 0 | 39 | +------------------------------------------+------------+------------+ [ 3.067186] audit: initializing netlink subsys (disabled) [ 3.068611] audit: type=2000 audit(1452176226.358:1): initialized [ 3.068611] audit: type=2000 audit(1452176226.358:1): initialized [ 3.870718] BUG: unable to handle kernel [ 3.870718] BUG: unable to handle kernel NULL pointer dereferenceNULL pointer dereference at 00000100 at 00000100 [ 3.872615] IP: [ 3.872615] IP: [] __queue_work+0x26/0x390 [] __queue_work+0x26/0x390 [ 3.873758] *pdpt = 0000000000000000 [ 3.873758] *pdpt = 0000000000000000 *pde = f000ff53f000ff53 *pde = f000ff53f000ff53 [ 3.875096] Oops: 0000 [#1] [ 3.875096] Oops: 0000 [#1] PREEMPT PREEMPT SMP SMP [ 3.876130] CPU: 0 PID: 24 Comm: kworker/0:1 Not tainted 4.4.0-rc4-00139-g373ccbe #1 [ 3.876130] CPU: 0 PID: 24 Comm: kworker/0:1 Not tainted 4.4.0-rc4-00139-g373ccbe #1 [ 3.878135] Workqueue: events vmstat_shepherd [ 3.878135] Workqueue: events vmstat_shepherd [ 3.879207] task: cb684600 ti: cb7ba000 task.ti: cb7ba000 [ 3.879207] task: cb684600 ti: cb7ba000 task.ti: cb7ba000 [ 3.880445] EIP: 0060:[] EFLAGS: 00010046 CPU: 0 [ 3.880445] EIP: 0060:[] EFLAGS: 00010046 CPU: 0 [ 3.881704] EIP is at __queue_work+0x26/0x390 [ 3.881704] EIP is at __queue_work+0x26/0x390 [ 3.882823] EAX: 00000046 EBX: cbb37800 ECX: cbb37800 EDX: 00000000 [ 3.882823] EAX: 00000046 EBX: cbb37800 ECX: cbb37800 EDX: 00000000 [ 3.884457] ESI: 00000000 EDI: 00000000 EBP: cb7bbe68 ESP: cb7bbe38 [ 3.884457] ESI: 00000000 EDI: 00000000 EBP: cb7bbe68 ESP: cb7bbe38 [ 3.886005] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 [ 3.886005] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 [ 3.887229] CR0: 8005003b CR2: 00000100 CR3: 01fd5000 CR4: 000006b0 [ 3.887229] CR0: 8005003b CR2: 00000100 CR3: 01fd5000 CR4: 000006b0 [ 3.888663] Stack: [ 3.888663] Stack: [ 3.889199] c1e5fccc [ 3.889199] c1e5fccc 00000000 00000000 c1a381dd c1a381dd cb684acc cb684acc c1e5fccc c1e5fccc 00000246 00000246 c1e5fccc c1e5fccc 00000000 00000000 [ 3.891351] 00000246 [ 3.891351] 00000246 00000000 00000000 00000000 00000000 cbb37820 cbb37820 cb7bbe80 cb7bbe80 c1075221 c1075221 ffffffff ffffffff 00000246 00000246 [ 3.893339] 00000000 [ 3.893339] 00000000 00000000 00000000 cb7bbe98 cb7bbe98 c10764c6 c10764c6 00000000 00000000 c1f1d400 c1f1d400 00000000 00000000 c1fc3800 c1fc3800 [ 3.895204] Call Trace: [ 3.895204] Call Trace: [ 3.895854] [] ? mutex_unlock+0xd/0x10 [ 3.895854] [] ? mutex_unlock+0xd/0x10 [ 3.897120] [] __queue_delayed_work+0xa1/0x160 [ 3.897120] [] __queue_delayed_work+0xa1/0x160 [ 3.898530] [] queue_delayed_work_on+0x36/0x60 [ 3.898530] [] queue_delayed_work_on+0x36/0x60 [ 3.899790] [] vmstat_shepherd+0xad/0xf0 [ 3.899790] [] vmstat_shepherd+0xad/0xf0 [ 3.900899] [] process_one_work+0x1aa/0x4c0 [ 3.900899] [] process_one_work+0x1aa/0x4c0 [ 3.902093] [] ? process_one_work+0x112/0x4c0 [ 3.902093] [] ? process_one_work+0x112/0x4c0 [ 3.903520] [] ? do_raw_spin_lock+0xe/0x150 [ 3.903520] [] ? do_raw_spin_lock+0xe/0x150 [ 3.904853] [] worker_thread+0x41/0x440 [ 3.904853] [] worker_thread+0x41/0x440 [ 3.906023] [] ? process_one_work+0x4c0/0x4c0 [ 3.906023] [] ? process_one_work+0x4c0/0x4c0 [ 3.907242] [] kthread+0xb0/0xd0 [ 3.907242] [] kthread+0xb0/0xd0 [ 3.908188] [] ret_from_kernel_thread+0x21/0x40 [ 3.908188] [] ret_from_kernel_thread+0x21/0x40 [ 3.909601] [] ? __kthread_parkme+0x80/0x80 [ 3.909601] [] ? __kthread_parkme+0x80/0x80 [ 3.910941] Code: [ 3.910941] Code: 27 27 00 00 00 00 00 00 00 00 55 55 89 89 e5 e5 57 57 56 56 53 53 83 83 ec ec 24 24 e8 e8 82 82 87 87 9c 9c 00 00 89 89 c7 c7 89 89 d6 d6 89 89 cb cb 89 89 45 45 ec ec 9c 9c 58 58 8d 8d 74 74 26 26 00 00 f6 f6 c4 c4 02 02 0f 0f 85 85 ca ca 02 02 00 00 00 00 <8b> <8b> 86 86 00 00 01 01 00 00 00 00 a9 a9 00 00 00 00 01 01 00 00 0f 0f 85 85 83 83 02 02 00 00 00 00 69 69 d3 d3 01 01 00 00 [ 3.916531] EIP: [] [ 3.916531] EIP: [] __queue_work+0x26/0x390__queue_work+0x26/0x390 SS:ESP 0068:cb7bbe38 SS:ESP 0068:cb7bbe38 [ 3.918387] CR2: 0000000000000100 [ 3.918387] CR2: 0000000000000100 [ 3.919198] ---[ end trace 2094b665a03d1cdc ]--- [ 3.919198] ---[ end trace 2094b665a03d1cdc ]--- [ 3.920255] Kernel panic - not syncing: Fatal exception [ 3.920255] Kernel panic - not syncing: Fatal exception [ 3.921470] Kernel Offset: disabled [ 3.921470] Kernel Offset: disabled Thanks, Ying Huang