INFO: task khugepaged:1085 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 D27376 1085 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: 4 locks held by kworker/u4:3/140: #0: ffff8880a7420528 ((wq_completion)writeback){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8880a7420528 ((wq_completion)writeback){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880a7420528 ((wq_completion)writeback){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8880a7420528 ((wq_completion)writeback){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8880a7420528 ((wq_completion)writeback){+.+.}, at: set_work_data kernel/workqueue.c:614 [inline] #0: ffff8880a7420528 ((wq_completion)writeback){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:641 [inline] #0: ffff8880a7420528 ((wq_completion)writeback){+.+.}, at: process_one_work+0x88b/0x1740 kernel/workqueue.c:2234 #1: ffff8880a962fdc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0x8c1/0x1740 kernel/workqueue.c:2238 #2: ffff8882158740d8 (&type->s_umount_key#32){++++}, at: trylock_super+0x22/0x110 fs/super.c:418 #3: ffff888215876990 (&sbi->s_journal_flag_rwsem){.+.+}, at: do_writepages+0xfa/0x2a0 mm/page-writeback.c:2344 1 lock held by khungtaskd/1078: #0: ffffffff88faba40 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279 kernel/locking/lockdep.c:5336 1 lock held by khugepaged/1085: #0: ffff888215876990 (&sbi->s_journal_flag_rwsem){.+.+}, at: do_writepages+0xfa/0x2a0 mm/page-writeback.c:2344 1 lock held by rsyslogd/8699: 2 locks held by getty/8789: #0: ffff8880a1ba4090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f352e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8790: #0: ffff8880a7df5090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f192e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8791: #0: ffff8880a3cfc090 (&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/8792: #0: ffff888090738090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f3f2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8793: #0: ffff8880983ea090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f432e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8794: #0: ffff8880a755c090 (&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 getty/8795: #0: ffff888096a9d090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f112e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.0/10210: #0: ffff8880a3312240 (&sb->s_type->i_mutex_key#12){+.+.}, at: inode_lock include/linux/fs.h:791 [inline] #0: ffff8880a3312240 (&sb->s_type->i_mutex_key#12){+.+.}, at: __sock_release+0x89/0x280 net/socket.c:590 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1078 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 3999 Comm: udevd 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:lookup_object lib/debugobjects.c:193 [inline] RIP: 0010:debug_object_activate+0x1a1/0x470 lib/debugobjects.c:634 Code: 3c 32 00 0f 85 3f 02 00 00 4d 8b 24 24 4d 85 e4 0f 84 a5 00 00 00 49 8d 7c 24 18 83 c3 01 48 89 fa 48 c1 ea 03 42 80 3c 32 00 <0f> 85 f0 01 00 00 4d 3b 6c 24 18 75 c0 49 8d 7c 24 10 48 b8 00 00 RSP: 0018:ffff8880ae909b70 EFLAGS: 00000046 RAX: 1ffffffff15a3608 RBX: 0000000000000004 RCX: ffffffff815a7e2a RDX: 1ffff11014e972c0 RSI: 0000000000000086 RDI: ffff8880a74b9600 RBP: ffff8880ae909c60 R08: ffffffff88f7b5c0 R09: ffffffff8ad1b048 R10: ffffed1015d2135a R11: 0000000000000003 R12: ffff8880a74b95e8 R13: ffff88806469d518 R14: dffffc0000000000 R15: 1ffff11015d21372 FS: 00007faddf04c7a0(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000000961da000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: debug_work_activate kernel/workqueue.c:488 [inline] __queue_work+0xcf/0x1280 kernel/workqueue.c:1405 delayed_work_timer_fn+0x5d/0x90 kernel/workqueue.c:1610 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1404 expire_timers kernel/time/timer.c:1444 [inline] __run_timers kernel/time/timer.c:1773 [inline] __run_timers kernel/time/timer.c:1740 [inline] run_timer_softirq+0x48c/0x1790 kernel/time/timer.c:1786 __do_softirq+0x262/0x98c kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x19b/0x1e0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1137 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:756 [inline] RIP: 0010:console_trylock_spinning kernel/printk/printk.c:1751 [inline] RIP: 0010:vprintk_emit+0x5da/0x700 kernel/printk/printk.c:1995 Code: 00 48 b8 00 00 00 00 00 fc ff df 41 80 3c 06 00 0f 85 f8 00 00 00 48 83 3d a2 3d 96 07 00 74 6a e8 4b 81 16 00 48 89 df 57 9d <0f> 1f 44 00 00 e9 06 ff ff ff e8 37 81 16 00 49 c1 ee 03 e8 7e 01 RSP: 0018:ffff8880962ef9b0 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13 RAX: ffff8880962e2600 RBX: 0000000000000293 RCX: 0000000000000007 RDX: 0000000000000000 RSI: ffffffff815ce445 RDI: 0000000000000293 RBP: ffff8880962ef9f8 R08: 1ffffffff14f3d3c R09: fffffbfff14f3d3d R10: fffffbfff14f3d3c R11: ffffffff8a79e9e7 R12: 000000000000005a R13: 0000000000000200 R14: 1ffffffff11e643c R15: ffff8880a7c823c0 vprintk_default+0x28/0x30 kernel/printk/printk.c:2023 vprintk_func+0x7e/0x189 kernel/printk/printk_safe.c:386 printk+0xba/0xed kernel/printk/printk.c:2056 fill_kobj_path lib/kobject.c:160 [inline] kobject_get_path.cold+0x38/0x47 lib/kobject.c:182 kobject_uevent_env+0x3ab/0x1023 lib/kobject_uevent.c:528 kobject_synth_uevent.cold+0xa0/0x10a lib/kobject_uevent.c:208 uevent_store+0x25/0x60 drivers/base/core.c:1421 dev_attr_store+0x57/0x80 drivers/base/core.c:1124 sysfs_kf_write+0x116/0x170 fs/sysfs/file.c:138 kernfs_fop_write+0x270/0x4a0 fs/kernfs/file.c:315 __vfs_write+0x8a/0x110 fs/read_write.c:494 vfs_write+0x268/0x5d0 fs/read_write.c:558 ksys_write+0x14f/0x290 fs/read_write.c:611 __do_sys_write fs/read_write.c:623 [inline] __se_sys_write fs/read_write.c:620 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:620 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7fadde754370 Code: 73 01 c3 48 8b 0d c8 4a 2b 00 31 d2 48 29 c2 64 89 11 48 83 c8 ff eb ea 90 90 83 3d 85 a2 2b 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 0e 8a 01 00 48 89 04 24 RSP: 002b:00007ffe37888488 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000001b87220 RCX: 00007fadde754370 RDX: 0000000000000006 RSI: 000000000041f4f9 RDI: 000000000000000b RBP: 0000000001b7fdb0 R08: 000000000041f4f1 R09: 00007fadde7aa7d0 R10: 7269762f73656369 R11: 0000000000000246 R12: 000000000000000b R13: 0000000000000000 R14: 0000000001b87220 R15: 0000000001b6e250