bisecting fixing commit since a1b977b49b66c75e6c51a515f6700371ae720217 building syzkaller on fc7735a27949755327024847e12dcc1b868bcb99 testing commit a1b977b49b66c75e6c51a515f6700371ae720217 with gcc (GCC) 8.4.1 20210217 kernel signature: e8a178bf874ec8f2e5b9d14f45af692a0d35cd0e0fb9a6798f220990d9a26a72 all runs: crashed: INFO: task hung in sync_inodes_sb testing current HEAD 255b58a2b3af0baa0ee11507390349217b8b73b0 testing commit 255b58a2b3af0baa0ee11507390349217b8b73b0 with gcc (GCC) 8.4.1 20210217 kernel signature: c9a928bd80aa4c15048f3811b6f1ada4134d890b520b3ba9f4bf6a4921ca9495 all runs: crashed: INFO: task hung in sync_inodes_sb revisions tested: 2, total time: 30m39.499411082s (build: 15m47.374473231s, test: 13m57.580775845s) the crash still happens on HEAD commit msg: Linux 4.19.176 crash: INFO: task hung in sync_inodes_sb Bluetooth: hci0: command 0x0406 tx timeout Bluetooth: hci1: command 0x0406 tx timeout Bluetooth: hci2: command 0x0406 tx timeout Bluetooth: hci5: command 0x0406 tx timeout Bluetooth: hci4: command 0x0406 tx timeout INFO: task syz-executor.2:5914 blocked for more than 140 seconds. Not tainted 4.19.176-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D23592 5914 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 wb_wait_for_completion+0x14f/0x1c0 fs/fs-writeback.c:222 sync_inodes_sb+0x183/0x8e0 fs/fs-writeback.c:2479 __sync_filesystem fs/sync.c:34 [inline] sync_filesystem fs/sync.c:67 [inline] sync_filesystem+0x114/0x1f0 fs/sync.c:48 generic_shutdown_super+0x69/0x330 fs/super.c:442 kill_block_super+0x96/0xe0 fs/super.c:1185 deactivate_locked_super+0x77/0xd0 fs/super.c:329 deactivate_super fs/super.c:360 [inline] deactivate_super+0x13f/0x160 fs/super.c:356 cleanup_mnt+0xa3/0x130 fs/namespace.c:1098 __cleanup_mnt+0xd/0x10 fs/namespace.c:1105 task_work_run+0x108/0x180 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x185/0x1e0 arch/x86/entry/common.c:167 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x413/0x4e0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x466ca7 Code: Bad RIP value. RSP: 002b:00007ffca13c6018 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000466ca7 RDX: 00007ffca13c60e9 RSI: 0000000000000002 RDI: 00007ffca13c60e0 RBP: 00007ffca13c60e0 R08: 00000000ffffffff R09: 00007ffca13c5eb0 R10: 00000000016c38ab R11: 0000000000000246 R12: 00000000004ae4c5 R13: 00007ffca13c7190 R14: 00000000016c3810 R15: 0000000000000002 INFO: task syz-executor.0:5915 blocked for more than 140 seconds. Not tainted 4.19.176-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D23032 5915 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 wb_wait_for_completion+0x14f/0x1c0 fs/fs-writeback.c:222 sync_inodes_sb+0x183/0x8e0 fs/fs-writeback.c:2479 __sync_filesystem fs/sync.c:34 [inline] sync_filesystem fs/sync.c:67 [inline] sync_filesystem+0x114/0x1f0 fs/sync.c:48 generic_shutdown_super+0x69/0x330 fs/super.c:442 kill_block_super+0x96/0xe0 fs/super.c:1185 deactivate_locked_super+0x77/0xd0 fs/super.c:329 deactivate_super fs/super.c:360 [inline] deactivate_super+0x13f/0x160 fs/super.c:356 cleanup_mnt+0xa3/0x130 fs/namespace.c:1098 __cleanup_mnt+0xd/0x10 fs/namespace.c:1105 task_work_run+0x108/0x180 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x185/0x1e0 arch/x86/entry/common.c:167 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x413/0x4e0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x466ca7 Code: Bad RIP value. RSP: 002b:00007ffed3a50ef8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000466ca7 RDX: 00007ffed3a50fc9 RSI: 0000000000000002 RDI: 00007ffed3a50fc0 RBP: 00007ffed3a50fc0 R08: 00000000ffffffff R09: 00007ffed3a50d90 R10: 00000000028e58ab R11: 0000000000000246 R12: 00000000004ae4c5 R13: 00007ffed3a52070 R14: 00000000028e5810 R15: 0000000000000002 INFO: task syz-executor.1:5917 blocked for more than 140 seconds. Not tainted 4.19.176-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D23752 5917 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 wb_wait_for_completion+0x14f/0x1c0 fs/fs-writeback.c:222 sync_inodes_sb+0x183/0x8e0 fs/fs-writeback.c:2479 __sync_filesystem fs/sync.c:34 [inline] sync_filesystem fs/sync.c:67 [inline] sync_filesystem+0x114/0x1f0 fs/sync.c:48 generic_shutdown_super+0x69/0x330 fs/super.c:442 kill_block_super+0x96/0xe0 fs/super.c:1185 deactivate_locked_super+0x77/0xd0 fs/super.c:329 deactivate_super fs/super.c:360 [inline] deactivate_super+0x13f/0x160 fs/super.c:356 cleanup_mnt+0xa3/0x130 fs/namespace.c:1098 __cleanup_mnt+0xd/0x10 fs/namespace.c:1105 task_work_run+0x108/0x180 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x185/0x1e0 arch/x86/entry/common.c:167 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x413/0x4e0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x466ca7 Code: Bad RIP value. RSP: 002b:00007ffccce1c068 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000466ca7 RDX: 00007ffccce1c139 RSI: 0000000000000002 RDI: 00007ffccce1c130 RBP: 00007ffccce1c130 R08: 00000000ffffffff R09: 00007ffccce1bf00 R10: 0000000001c7a8ab R11: 0000000000000246 R12: 00000000004ae4c5 R13: 00007ffccce1d1e0 R14: 0000000001c7a810 R15: 0000000000000002 INFO: task syz-executor.3:5919 blocked for more than 140 seconds. Not tainted 4.19.176-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D23736 5919 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 wb_wait_for_completion+0x14f/0x1c0 fs/fs-writeback.c:222 sync_inodes_sb+0x183/0x8e0 fs/fs-writeback.c:2479 __sync_filesystem fs/sync.c:34 [inline] sync_filesystem fs/sync.c:67 [inline] sync_filesystem+0x114/0x1f0 fs/sync.c:48 generic_shutdown_super+0x69/0x330 fs/super.c:442 kill_block_super+0x96/0xe0 fs/super.c:1185 deactivate_locked_super+0x77/0xd0 fs/super.c:329 deactivate_super fs/super.c:360 [inline] deactivate_super+0x13f/0x160 fs/super.c:356 cleanup_mnt+0xa3/0x130 fs/namespace.c:1098 __cleanup_mnt+0xd/0x10 fs/namespace.c:1105 task_work_run+0x108/0x180 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x185/0x1e0 arch/x86/entry/common.c:167 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x413/0x4e0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x466ca7 Code: Bad RIP value. RSP: 002b:00007ffc643d3d48 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000466ca7 RDX: 00007ffc643d3e19 RSI: 0000000000000002 RDI: 00007ffc643d3e10 RBP: 00007ffc643d3e10 R08: 00000000ffffffff R09: 00007ffc643d3be0 R10: 00000000031148ab R11: 0000000000000246 R12: 00000000004ae4c5 R13: 00007ffc643d4ec0 R14: 0000000003114810 R15: 0000000000000002 INFO: task syz-executor.5:5921 blocked for more than 140 seconds. Not tainted 4.19.176-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D23816 5921 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 wb_wait_for_completion+0x14f/0x1c0 fs/fs-writeback.c:222 sync_inodes_sb+0x183/0x8e0 fs/fs-writeback.c:2479 __sync_filesystem fs/sync.c:34 [inline] sync_filesystem fs/sync.c:67 [inline] sync_filesystem+0x114/0x1f0 fs/sync.c:48 generic_shutdown_super+0x69/0x330 fs/super.c:442 kill_block_super+0x96/0xe0 fs/super.c:1185 deactivate_locked_super+0x77/0xd0 fs/super.c:329 deactivate_super fs/super.c:360 [inline] deactivate_super+0x13f/0x160 fs/super.c:356 cleanup_mnt+0xa3/0x130 fs/namespace.c:1098 __cleanup_mnt+0xd/0x10 fs/namespace.c:1105 task_work_run+0x108/0x180 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x185/0x1e0 arch/x86/entry/common.c:167 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x413/0x4e0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x466ca7 Code: Bad RIP value. RSP: 002b:00007ffd43e64368 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000466ca7 RDX: 00007ffd43e64439 RSI: 0000000000000002 RDI: 00007ffd43e64430 RBP: 00007ffd43e64430 R08: 00000000ffffffff R09: 00007ffd43e64200 R10: 0000000001e218ab R11: 0000000000000246 R12: 00000000004ae4c5 R13: 00007ffd43e654e0 R14: 0000000001e21810 R15: 0000000000000002 INFO: task syz-executor.4:5922 blocked for more than 140 seconds. Not tainted 4.19.176-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D23736 5922 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 wb_wait_for_completion+0x14f/0x1c0 fs/fs-writeback.c:222 sync_inodes_sb+0x183/0x8e0 fs/fs-writeback.c:2479 __sync_filesystem fs/sync.c:34 [inline] sync_filesystem fs/sync.c:67 [inline] sync_filesystem+0x114/0x1f0 fs/sync.c:48 generic_shutdown_super+0x69/0x330 fs/super.c:442 kill_block_super+0x96/0xe0 fs/super.c:1185 deactivate_locked_super+0x77/0xd0 fs/super.c:329 deactivate_super fs/super.c:360 [inline] deactivate_super+0x13f/0x160 fs/super.c:356 cleanup_mnt+0xa3/0x130 fs/namespace.c:1098 __cleanup_mnt+0xd/0x10 fs/namespace.c:1105 task_work_run+0x108/0x180 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x185/0x1e0 arch/x86/entry/common.c:167 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x413/0x4e0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x466ca7 Code: Bad RIP value. RSP: 002b:00007fffd1353dd8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000466ca7 RDX: 00007fffd1353ea9 RSI: 0000000000000002 RDI: 00007fffd1353ea0 RBP: 00007fffd1353ea0 R08: 00000000ffffffff R09: 00007fffd1353c70 R10: 00000000025e78ab R11: 0000000000000246 R12: 00000000004ae4c5 R13: 00007fffd1354f50 R14: 00000000025e7810 R15: 0000000000000002 Showing all locks held in the system: 2 locks held by kworker/u4:1/23: #0: 00000000eb8a9632 ((wq_completion)"writeback"){+.+.}, at: process_one_work+0x6e8/0x15a0 kernel/workqueue.c:2123 #1: 00000000e99c091e ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0x71b/0x15a0 kernel/workqueue.c:2127 2 locks held by kworker/u4:2/31: #0: 00000000eb8a9632 ((wq_completion)"writeback"){+.+.}, at: process_one_work+0x6e8/0x15a0 kernel/workqueue.c:2123 #1: 0000000029d776d1 ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0x71b/0x15a0 kernel/workqueue.c:2127 2 locks held by kworker/u4:4/696: #0: 00000000eb8a9632 ((wq_completion)"writeback"){+.+.}, at: process_one_work+0x6e8/0x15a0 kernel/workqueue.c:2123 #1: 0000000096c19c9d ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0x71b/0x15a0 kernel/workqueue.c:2127 1 lock held by khungtaskd/1094: #0: 0000000082a9fcdc (rcu_read_lock){....}, at: debug_show_all_locks+0x5b/0x27a kernel/locking/lockdep.c:4442 1 lock held by in:imklog/5572: 2 locks held by kworker/u4:5/5758: #0: 00000000eb8a9632 ((wq_completion)"writeback"){+.+.}, at: process_one_work+0x6e8/0x15a0 kernel/workqueue.c:2123 #1: 000000000a22b671 ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0x71b/0x15a0 kernel/workqueue.c:2127 2 locks held by syz-executor.2/5914: #0: 00000000d6de42bf (&type->s_umount_key#50){+.+.}, at: deactivate_super fs/super.c:359 [inline] #0: 00000000d6de42bf (&type->s_umount_key#50){+.+.}, at: deactivate_super+0x137/0x160 fs/super.c:356 #1: 00000000eb50e1e5 (&bdi->wb_switch_rwsem){+.+.}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:338 [inline] #1: 00000000eb50e1e5 (&bdi->wb_switch_rwsem){+.+.}, at: sync_inodes_sb+0x16a/0x8e0 fs/fs-writeback.c:2477 2 locks held by syz-executor.0/5915: #0: 00000000f92d40a3 (&type->s_umount_key#50){+.+.}, at: deactivate_super fs/super.c:359 [inline] #0: 00000000f92d40a3 (&type->s_umount_key#50){+.+.}, at: deactivate_super+0x137/0x160 fs/super.c:356 #1: 000000008da76370 (&bdi->wb_switch_rwsem){+.+.}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:338 [inline] #1: 000000008da76370 (&bdi->wb_switch_rwsem){+.+.}, at: sync_inodes_sb+0x16a/0x8e0 fs/fs-writeback.c:2477 2 locks held by syz-executor.1/5917: #0: 00000000f115937e (&type->s_umount_key#50){+.+.}, at: deactivate_super fs/super.c:359 [inline] #0: 00000000f115937e (&type->s_umount_key#50){+.+.}, at: deactivate_super+0x137/0x160 fs/super.c:356 #1: 0000000013886a1c (&bdi->wb_switch_rwsem){+.+.}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:338 [inline] #1: 0000000013886a1c (&bdi->wb_switch_rwsem){+.+.}, at: sync_inodes_sb+0x16a/0x8e0 fs/fs-writeback.c:2477 2 locks held by syz-executor.3/5919: #0: 00000000ef8b4e78 (&type->s_umount_key#50){+.+.}, at: deactivate_super fs/super.c:359 [inline] #0: 00000000ef8b4e78 (&type->s_umount_key#50){+.+.}, at: deactivate_super+0x137/0x160 fs/super.c:356 #1: 00000000a9ec83ac (&bdi->wb_switch_rwsem){+.+.}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:338 [inline] #1: 00000000a9ec83ac (&bdi->wb_switch_rwsem){+.+.}, at: sync_inodes_sb+0x16a/0x8e0 fs/fs-writeback.c:2477 2 locks held by syz-executor.5/5921: #0: 00000000f73510fb (&type->s_umount_key#50){+.+.}, at: deactivate_super fs/super.c:359 [inline] #0: 00000000f73510fb (&type->s_umount_key#50){+.+.}, at: deactivate_super+0x137/0x160 fs/super.c:356 #1: 0000000001f5c76c (&bdi->wb_switch_rwsem){+.+.}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:338 [inline] #1: 0000000001f5c76c (&bdi->wb_switch_rwsem){+.+.}, at: sync_inodes_sb+0x16a/0x8e0 fs/fs-writeback.c:2477 2 locks held by syz-executor.4/5922: #0: 000000002c30b38a (&type->s_umount_key#50){+.+.}, at: deactivate_super fs/super.c:359 [inline] #0: 000000002c30b38a (&type->s_umount_key#50){+.+.}, at: deactivate_super+0x137/0x160 fs/super.c:356 #1: 00000000dc4731b2 (&bdi->wb_switch_rwsem){+.+.}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:338 [inline] #1: 00000000dc4731b2 (&bdi->wb_switch_rwsem){+.+.}, at: sync_inodes_sb+0x16a/0x8e0 fs/fs-writeback.c:2477 2 locks held by kworker/u4:6/6586: #0: 00000000eb8a9632 ((wq_completion)"writeback"){+.+.}, at: process_one_work+0x6e8/0x15a0 kernel/workqueue.c:2123 #1: 00000000ed196cee ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0x71b/0x15a0 kernel/workqueue.c:2127 2 locks held by kworker/u4:7/7243: #0: 00000000eb8a9632 ((wq_completion)"writeback"){+.+.}, at: process_one_work+0x6e8/0x15a0 kernel/workqueue.c:2123 #1: 0000000018f4f43b ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0x71b/0x15a0 kernel/workqueue.c:2127 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1094 Comm: khungtaskd Not tainted 4.19.176-syzkaller #0 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+0x17c/0x226 lib/dump_stack.c:118 nmi_cpu_backtrace.cold.0+0x3c/0x78 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0xf5/0x120 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x5c3/0xb40 kernel/hung_task.c:287 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 7 Comm: kworker/u4:0 Not tainted 4.19.176-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: (null) (phy5) RIP: 0010:put_pwq+0x8a/0x160 kernel/workqueue.c:1077 Code: 74 08 3c 03 0f 8e c6 00 00 00 83 6b 18 01 74 45 5b 41 5c 5d c3 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 80 3c 02 00 <0f> 85 b1 00 00 00 48 8b 03 be ff ff ff ff 48 8d 78 18 e8 7f 66 0c RSP: 0018:ffff8881f52bfd08 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffff8881dab8d400 RCX: ffffffff814b1680 RDX: 1ffff1103b571a80 RSI: 0000000000000000 RDI: ffffffff88bd8c60 RBP: ffff8881f52bfd18 R08: ffffed103ec02d29 R09: ffffed103ec02d28 R10: ffffed103ec02d28 R11: ffff8881f6016943 R12: 0000000000000000 R13: ffff8881dab8d460 R14: ffff8881dab8d41c R15: ffff8881dab8d400 FS: 0000000000000000(0000) GS:ffff8881f6600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000130 CR3: 000000000866d001 CR4: 00000000001606f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: pwq_dec_nr_in_flight+0x11f/0x2c0 kernel/workqueue.c:1176 process_one_work+0x9d0/0x15a0 kernel/workqueue.c:2191 worker_thread+0x85/0xb60 kernel/workqueue.c:2295 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415