INFO: task khugepaged:1084 blocked for more than 143 seconds. Not tainted 5.4.0-rc5-next-20191031 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. khugepaged D27224 1084 2 0x80004000 Call Trace: context_switch kernel/sched/core.c:3385 [inline] __schedule+0x94a/0x1e70 kernel/sched/core.c:4070 schedule+0xdc/0x2b0 kernel/sched/core.c:4144 io_schedule+0x1c/0x70 kernel/sched/core.c:5788 wait_on_page_bit_common mm/filemap.c:1175 [inline] __lock_page+0x422/0xab0 mm/filemap.c:1383 lock_page include/linux/pagemap.h:480 [inline] mpage_prepare_extent_to_map+0xb3f/0xf90 fs/ext4/inode.c:2668 ext4_writepages+0x954/0x2e70 fs/ext4/inode.c:2822 ? 0xffffffff81000000 do_writepages+0xfa/0x2a0 mm/page-writeback.c:2344 __filemap_fdatawrite_range+0x2bc/0x3b0 mm/filemap.c:421 __filemap_fdatawrite mm/filemap.c:429 [inline] filemap_flush+0x24/0x30 mm/filemap.c:456 collapse_file+0x36b1/0x41a0 mm/khugepaged.c:1652 khugepaged_scan_file mm/khugepaged.c:1890 [inline] khugepaged_scan_mm_slot mm/khugepaged.c:1988 [inline] khugepaged_do_scan mm/khugepaged.c:2072 [inline] khugepaged+0x2da9/0x4360 mm/khugepaged.c:2117 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Showing all locks held in the system: 3 locks held by kworker/u4:0/7: #0: ffff8880ae834d58 (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1215 [inline] #0: ffff8880ae834d58 (&rq->lock){-.-.}, at: __schedule+0x266/0x1e70 kernel/sched/core.c:4018 #1: ffffffff88faba40 (rcu_read_lock){....}, at: trace_sched_stat_runtime include/trace/events/sched.h:435 [inline] #1: ffffffff88faba40 (rcu_read_lock){....}, at: update_curr+0x2ea/0x8d0 kernel/sched/fair.c:860 #2: ffffffff88faba40 (rcu_read_lock){....}, at: batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:405 [inline] #2: ffffffff88faba40 (rcu_read_lock){....}, at: batadv_nc_worker+0xe3/0x760 net/batman-adv/network-coding.c:718 4 locks held by kworker/u4:1/21: #0: ffff8880a7ee8528 ((wq_completion)writeback){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8880a7ee8528 ((wq_completion)writeback){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880a7ee8528 ((wq_completion)writeback){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8880a7ee8528 ((wq_completion)writeback){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8880a7ee8528 ((wq_completion)writeback){+.+.}, at: set_work_data kernel/workqueue.c:614 [inline] #0: ffff8880a7ee8528 ((wq_completion)writeback){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:641 [inline] #0: ffff8880a7ee8528 ((wq_completion)writeback){+.+.}, at: process_one_work+0x88b/0x1740 kernel/workqueue.c:2234 #1: ffff8880a9a07dc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0x8c1/0x1740 kernel/workqueue.c:2238 #2: ffff888215ee60d8 (&type->s_umount_key#32){++++}, at: trylock_super+0x22/0x110 fs/super.c:418 #3: ffff888215ee8990 (&sbi->s_journal_flag_rwsem){.+.+}, at: do_writepages+0xfa/0x2a0 mm/page-writeback.c:2344 1 lock held by khungtaskd/1077: #0: ffffffff88faba40 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279 kernel/locking/lockdep.c:5336 1 lock held by khugepaged/1084: #0: ffff888215ee8990 (&sbi->s_journal_flag_rwsem){.+.+}, at: do_writepages+0xfa/0x2a0 mm/page-writeback.c:2344 1 lock held by rsyslogd/8722: #0: ffff88808aceb860 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/8812: #0: ffff8880a72b6090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f3d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8813: #0: ffff888091727090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f532e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8814: #0: ffff888096cf3090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f452e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8815: #0: ffff8880a4e99090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f492e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8816: #0: ffff888095bdc090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f292e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8817: #0: ffff88809a4e5090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f4f2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8818: #0: ffff88809a93a090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f212e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by syz-executor.2/8857: #0: ffff8880a314c7b8 (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x19b/0x1600 fs/block_dev.c:1553 #1: ffffffff89520dc0 (loop_ctl_mutex){+.+.}, at: lo_open+0x1d/0xd0 drivers/block/loop.c:1784 2 locks held by syz-executor.4/8862: #0: ffff888090e32838 (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x19b/0x1600 fs/block_dev.c:1553 #1: ffffffff89520dc0 (loop_ctl_mutex){+.+.}, at: lo_open+0x1d/0xd0 drivers/block/loop.c:1784 2 locks held by syz-executor.5/8864: #0: ffff8880a328b7f8 (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x19b/0x1600 fs/block_dev.c:1553 #1: ffffffff89520dc0 (loop_ctl_mutex){+.+.}, at: lo_open+0x1d/0xd0 drivers/block/loop.c:1784 1 lock held by syz-executor.3/9715: #0: ffffffff89520dc0 (loop_ctl_mutex){+.+.}, at: loop_set_status+0x93/0x1370 drivers/block/loop.c:1236 2 locks held by blkid/9724: #0: ffff888090e55878 (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x19b/0x1600 fs/block_dev.c:1553 #1: ffffffff89520dc0 (loop_ctl_mutex){+.+.}, at: lo_open+0x1d/0xd0 drivers/block/loop.c:1784 1 lock held by blkid/9732: #0: ffff8880a328b7f8 (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x19b/0x1600 fs/block_dev.c:1553 1 lock held by blkid/9733: #0: ffff888090e32838 (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x19b/0x1600 fs/block_dev.c:1553 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1077 Comm: khungtaskd Not tainted 5.4.0-rc5-next-20191031 #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+0x172/0x1f0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b 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:269 [inline] watchdog+0xc8f/0x1350 kernel/hung_task.c:353 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 9742 Comm: syz-executor.4 Not tainted 5.4.0-rc5-next-20191031 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:in_lock_functions+0x0/0x20 kernel/locking/spinlock.c:397 Code: 66 3e 55 00 e9 3e ff ff ff 48 c7 c7 40 86 12 8a e8 55 3e 55 00 eb 88 0f 1f 00 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <31> c0 48 81 ff 28 d8 57 87 72 0c 31 c0 48 81 ff cd e6 57 87 0f 92 RSP: 0018:ffff88805d9ff7a8 EFLAGS: 00000002 RAX: ffff88805d9ff7e0 RBX: ffffffff83499b41 RCX: 1ffffffff1561834 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff83499b41 RBP: ffff88805d9ff7c0 R08: ffff8880910e2480 R09: ffffffff8acd24c8 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff8acd24c8 R13: 0000000000000286 R14: dffffc0000000000 R15: 1ffff1100bb3ff02 FS: 00007fafd4158700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2d323000 CR3: 00000000646ec000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:109 [inline] _raw_spin_lock_irqsave+0x79/0xcd kernel/locking/spinlock.c:159 debug_object_activate+0x131/0x470 lib/debugobjects.c:632 debug_object_activate+0x2ae/0x470 lib/debugobjects.c:678 debug_rcu_head_queue kernel/rcu/rcu.h:176 [inline] __call_rcu+0x32/0x740 kernel/rcu/tree.c:2595 call_rcu+0xb/0x10 kernel/rcu/tree.c:2682 put_ctx kernel/events/core.c:1194 [inline] put_ctx+0xcd/0x120 kernel/events/core.c:1187 perf_event_exit_task_context kernel/events/core.c:11683 [inline] perf_event_exit_task+0x8a2/0xbc0 kernel/events/core.c:11712 do_exit+0x96c/0x2e60 kernel/exit.c:827 do_group_exit+0x135/0x360 kernel/exit.c:921 get_signal+0x47c/0x24f0 kernel/signal.c:2734 do_signal+0x87/0x1700 arch/x86/kernel/signal.c:815 exit_to_usermode_loop+0x286/0x380 arch/x86/entry/common.c:159 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline] syscall_return_slowpath arch/x86/entry/common.c:274 [inline] do_syscall_64+0x65f/0x760 arch/x86/entry/common.c:300 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a219 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fafd4157cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 000000000075bf28 RCX: 000000000045a219 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000075bf28 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000075bf2c R13: 00007ffecdf71e5f R14: 00007fafd41589c0 R15: 000000000075bf2c