bond0 (unregistering): Released all slaves buffer_io_error: 2 callbacks suppressed Buffer I/O error on dev loop0, logical block 15, async page read INFO: task syz-executor2:17599 blocked for more than 120 seconds. Not tainted 4.16.0+ #12 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor2 D22864 17599 9664 0x00000004 Call Trace: context_switch kernel/sched/core.c:2848 [inline] __schedule+0x8fb/0x1ef0 kernel/sched/core.c:3490 schedule+0xf5/0x430 kernel/sched/core.c:3549 io_schedule+0x1c/0x70 kernel/sched/core.c:5169 wait_on_page_bit_common+0x4b3/0x770 mm/filemap.c:1099 wait_on_page_bit mm/filemap.c:1132 [inline] wait_on_page_writeback include/linux/pagemap.h:546 [inline] __filemap_fdatawait_range+0x282/0x430 mm/filemap.c:533 filemap_fdatawait_keep_errors+0x2a/0xb0 mm/filemap.c:600 fdatawait_one_bdev+0x50/0x70 fs/sync.c:95 iterate_bdevs+0x109/0x260 fs/block_dev.c:2162 ksys_sync+0x120/0x1c0 fs/sync.c:117 sys_sync+0xe/0x20 fs/sync.c:124 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x4552d9 RSP: 002b:00007fa7cab94c68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007fa7cab956d4 RCX: 00000000004552d9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 000000000000064b R14: 00000000006fc7a8 R15: 0000000000000000 Showing all locks held in the system: 2 locks held by khungtaskd/877: #0: 0000000020e0f5f6 (rcu_read_lock){....}, at: check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline] #0: 0000000020e0f5f6 (rcu_read_lock){....}, at: watchdog+0x1d6/0xd70 kernel/hung_task.c:249 #1: 00000000d1e4e40c (tasklist_lock){.+.+}, at: debug_show_all_locks+0xd3/0x3d0 kernel/locking/lockdep.c:4470 3 locks held by kworker/u4:4/1861: #0: 000000006149b399 ((wq_completion)"writeback"){+.+.}, at: __write_once_size include/linux/compiler.h:215 [inline] #0: 000000006149b399 ((wq_completion)"writeback"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 000000006149b399 ((wq_completion)"writeback"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] #0: 000000006149b399 ((wq_completion)"writeback"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:57 [inline] #0: 000000006149b399 ((wq_completion)"writeback"){+.+.}, at: set_work_data kernel/workqueue.c:619 [inline] #0: 000000006149b399 ((wq_completion)"writeback"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: 000000006149b399 ((wq_completion)"writeback"){+.+.}, at: process_one_work+0xb83/0x1c40 kernel/workqueue.c:2084 #1: 000000000770cbfa ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0xbd9/0x1c40 kernel/workqueue.c:2088 #2: 00000000d3428333 (&type->s_umount_key#35){.+.+}, at: trylock_super+0x20/0x100 fs/super.c:395 1 lock held by rsyslogd/4357: #0: 00000000fb4c4c63 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x165/0x1a0 fs/file.c:766 2 locks held by getty/4447: #0: 000000009b82f961 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000119f0258 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4448: #0: 00000000629f14be (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000e36b9533 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4449: #0: 00000000abf9974c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000c94bfa10 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4450: #0: 00000000ca5c7d7d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000ad2a0ed3 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4451: #0: 00000000e313901d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000005a0ef3cf (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4452: #0: 0000000010bef049 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000006c493694 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4453: #0: 00000000d886959b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000cb92d974 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 1 lock held by blkid/17243: #0: 00000000fcabab55 (&bdev->bd_mutex){+.+.}, at: blkdev_put+0x2a/0x4f0 fs/block_dev.c:1808 1 lock held by syz-executor2/17599: #0: 00000000fcabab55 (&bdev->bd_mutex){+.+.}, at: iterate_bdevs+0xc8/0x260 fs/block_dev.c:2160 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 877 Comm: khungtaskd Not tainted 4.16.0+ #12 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1a7/0x27d lib/dump_stack.c:53 nmi_cpu_backtrace+0x1e0/0x220 lib/nmi_backtrace.c:103 nmi_trigger_cpumask_backtrace+0x123/0x180 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:138 [inline] check_hung_task kernel/hung_task.c:132 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:190 [inline] watchdog+0x969/0xd70 kernel/hung_task.c:249 kthread+0x33c/0x400 kernel/kthread.c:238 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:411 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:54