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 D27840 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/u4:0/7: #0: ffff88821b337d28 ((wq_completion)writeback){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff88821b337d28 ((wq_completion)writeback){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff88821b337d28 ((wq_completion)writeback){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff88821b337d28 ((wq_completion)writeback){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff88821b337d28 ((wq_completion)writeback){+.+.}, at: set_work_data kernel/workqueue.c:614 [inline] #0: ffff88821b337d28 ((wq_completion)writeback){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:641 [inline] #0: ffff88821b337d28 ((wq_completion)writeback){+.+.}, at: process_one_work+0x88b/0x1740 kernel/workqueue.c:2234 #1: ffff8880a988fdc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0x8c1/0x1740 kernel/workqueue.c:2238 #2: ffff88809acd00d8 (&type->s_umount_key#32){++++}, at: trylock_super+0x22/0x110 fs/super.c:418 #3: ffff88809acd2990 (&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/1085: #0: ffff88809acd2990 (&sbi->s_journal_flag_rwsem){.+.+}, at: do_writepages+0xfa/0x2a0 mm/page-writeback.c:2344 1 lock held by rsyslogd/8720: #0: ffff8880a1c5bd60 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/8810: #0: ffff8880a75ec090 (&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/8811: #0: ffff8880980b8090 (&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/8812: #0: ffff8880917e0090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f392e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8813: #0: ffff888097eb5090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f412e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/8814: #0: ffff888097805090 (&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/8815: #0: ffff88809fc30090 (&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/8816: #0: ffff8880a75c3090 (&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 2 locks held by syz-executor.0/8850: #0: ffff8880a6655738 (&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.1/8852: #0: ffff8880a6658778 (&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.2/8855: #0: ffff8880a04f41f8 (&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.3/8858: #0: ffff8880a6655138 (&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.5/8865: #0: ffff8880904bf278 (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x19b/0x1600 fs/block_dev.c:1553 1 lock held by syz-executor.4/9947: #0: ffffffff89520dc0 (loop_ctl_mutex){+.+.}, at: __loop_clr_fd+0x88/0xd60 drivers/block/loop.c:1093 1 lock held by blkid/9956: #0: ffff8880a6658778 (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x19b/0x1600 fs/block_dev.c:1553 2 locks held by blkid/9962: #0: ffff8880904bf278 (&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 ============================================= 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: 231 Comm: kworker/u4:3 Not tainted 5.4.0-rc5-next-20191031 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:__lock_acquire+0x235/0x4a00 kernel/locking/lockdep.c:3892 Code: 39 e6 75 09 48 85 db 0f 85 fc 11 00 00 4c 03 95 60 ff ff ff 44 89 e6 66 81 e6 ff 1f 49 8d 42 20 48 89 c2 48 89 85 50 ff ff ff <48> b8 00 00 00 00 00 fc ff df 48 c1 ea 03 0f b6 14 02 84 d2 74 09 RSP: 0018:ffff8880a9217b38 EFLAGS: 00000002 RAX: ffff8880a920ab90 RBX: 0000000000000000 RCX: 0000000000000002 RDX: ffff8880a920ab90 RSI: 0000000000000029 RDI: ffff8880a920ab68 RBP: ffff8880a9217c50 R08: 0000000000000000 R09: 1ffff1101524156d R10: ffff8880a920ab70 R11: ffff8880a920a280 R12: 0000000000000029 R13: 0000000000000000 R14: ffffffff88faba40 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2da25000 CR3: 0000000067947000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4487 rcu_lock_acquire include/linux/rcupdate.h:208 [inline] rcu_read_lock include/linux/rcupdate.h:617 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:407 [inline] batadv_nc_worker+0x117/0x760 net/batman-adv/network-coding.c:718 process_one_work+0x9af/0x1740 kernel/workqueue.c:2263 worker_thread+0x98/0xe40 kernel/workqueue.c:2409 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352