Buffer I/O error on dev loop0, logical block 33, async page read INFO: task syz-executor1:13923 blocked for more than 120 seconds. Not tainted 4.15.0+ #213 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor1 D22608 13923 4108 0x20020004 Call Trace: context_switch kernel/sched/core.c:2857 [inline] __schedule+0x8e2/0x2040 kernel/sched/core.c:3435 schedule+0xf5/0x430 kernel/sched/core.c:3494 io_schedule+0x1c/0x70 kernel/sched/core.c:5110 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 file_write_and_wait_range+0xd7/0x100 mm/filemap.c:756 blkdev_fsync+0x67/0xb0 fs/block_dev.c:623 vfs_fsync_range+0x110/0x260 fs/sync.c:196 vfs_fsync fs/sync.c:210 [inline] do_fsync+0x42/0x70 fs/sync.c:220 SYSC_fdatasync fs/sync.c:233 [inline] SyS_fdatasync+0x19/0x20 fs/sync.c:231 do_syscall_32_irqs_on arch/x86/entry/common.c:330 [inline] do_fast_syscall_32+0x3ee/0xfa1 arch/x86/entry/common.c:392 entry_SYSENTER_compat+0x54/0x63 arch/x86/entry/entry_64_compat.S:129 RIP: 0023:0xf7fadc79 RSP: 002b:00000000f77a908c EFLAGS: 00000296 ORIG_RAX: 0000000000000094 RAX: ffffffffffffffda RBX: 0000000000000013 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 3 locks held by kworker/u4:3/249: #0: ((wq_completion)"writeback"){+.+.}, at: [<00000000bad0af82>] process_one_work+0xaaf/0x1af0 kernel/workqueue.c:2084 #1: ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: [<000000000e0a7d7c>] process_one_work+0xb01/0x1af0 kernel/workqueue.c:2088 #2: (&type->s_umount_key#27){.+.+}, at: [<0000000021a43949>] trylock_super+0x20/0x100 fs/super.c:395 2 locks held by khungtaskd/759: #0: (rcu_read_lock){....}, at: [<000000003277d434>] check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline] #0: (rcu_read_lock){....}, at: [<000000003277d434>] watchdog+0x1c5/0xd60 kernel/hung_task.c:249 #1: (tasklist_lock){.+.+}, at: [<000000002fd1d8c1>] debug_show_all_locks+0xd3/0x3d0 kernel/locking/lockdep.c:4470 2 locks held by getty/4027: #0: (&tty->ldisc_sem){++++}, at: [<0000000030944d9b>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<000000003cf9e5e6>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4028: #0: (&tty->ldisc_sem){++++}, at: [<0000000030944d9b>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<000000003cf9e5e6>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4029: #0: (&tty->ldisc_sem){++++}, at: [<0000000030944d9b>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<000000003cf9e5e6>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4030: #0: (&tty->ldisc_sem){++++}, at: [<0000000030944d9b>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<000000003cf9e5e6>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4031: #0: (&tty->ldisc_sem){++++}, at: [<0000000030944d9b>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<000000003cf9e5e6>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4032: #0: (&tty->ldisc_sem){++++}, at: [<0000000030944d9b>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<000000003cf9e5e6>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 2 locks held by getty/4033: #0: (&tty->ldisc_sem){++++}, at: [<0000000030944d9b>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<000000003cf9e5e6>] n_tty_read+0x2ef/0x1a00 drivers/tty/n_tty.c:2131 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 759 Comm: khungtaskd Not tainted 4.15.0+ #213 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+0x194/0x257 lib/dump_stack.c:53 nmi_cpu_backtrace+0x1d2/0x210 lib/nmi_backtrace.c:103 nmi_trigger_cpumask_backtrace+0x122/0x180 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+0x90c/0xd60 kernel/hung_task.c:249 kthread+0x33c/0x400 kernel/kthread.c:238 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:429 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.15.0+ #213 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__scd_stamp kernel/sched/clock.c:130 [inline] RIP: 0010:sched_clock_idle_wakeup_event+0x0/0x180 kernel/sched/clock.c:394 RSP: 0018:ffff8801db407d20 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff8801db426620 RCX: ffffffff816435c2 RDX: 1ffff1003b684cd4 RSI: ffff8801db426620 RDI: ffff8801db4266c8 RBP: ffff8801db407d48 R08: ffff88021fff801c R09: ffff88021fff8008 R10: ffff88021fff8010 R11: ffff88021fff801d R12: ffff8801db426684 R13: ffff8801db4266a0 R14: 000000563594c1a1 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8801db400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000022e30b8 CR3: 0000000006a22006 CR4: 00000000001606f0 DR0: 0000000020000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000008 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: irq_enter+0xb6/0xd0 kernel/softirq.c:346 scheduler_ipi+0x23d/0x820 kernel/sched/core.c:1794 smp_reschedule_interrupt+0xe6/0x650 arch/x86/kernel/smp.c:277 reschedule_interrupt+0xa9/0xb0 arch/x86/entry/entry_64.S:853 RIP: 0010:native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:54 RSP: 0018:ffffffff86a07c38 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff02 RAX: dffffc0000000000 RBX: 1ffffffff0d40f8a RCX: 0000000000000000 RDX: 1ffffffff0d59278 RSI: 0000000000000001 RDI: ffffffff86ac93c0 RBP: ffffffff86a07c38 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffffffff86a07cf0 R14: ffffffff87269560 R15: 0000000000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:93 [inline] default_idle+0xbf/0x430 arch/x86/kernel/process.c:354 arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:345 default_idle_call+0x36/0x90 kernel/sched/idle.c:98 cpuidle_idle_call kernel/sched/idle.c:156 [inline] do_idle+0x24a/0x3b0 kernel/sched/idle.c:246 cpu_startup_entry+0x104/0x120 kernel/sched/idle.c:351 rest_init+0xed/0xf0 init/main.c:436 start_kernel+0x7f1/0x819 init/main.c:716 x86_64_start_reservations+0x2a/0x2c arch/x86/kernel/head64.c:378 x86_64_start_kernel+0x77/0x7a arch/x86/kernel/head64.c:359 secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:237 Code: e8 76 e8 5a 00 e9 2a ff ff ff 48 89 df 48 89 45 f0 e8 25 e9 5a 00 48 8b 45 f0 eb ca 48 89 45 f0 e8 16 e9 5a 00 48 8b 45 f0 eb 9b <55> 48 89 e5 53 0f 1f 44 00 00 5b 5d c3 48 c7 c7 f4 96 26 87 48