Buffer I/O error on dev loop0, logical block 6, lost async page write Buffer I/O error on dev loop0, logical block 7, lost async page write Buffer I/O error on dev loop0, logical block 8, lost async page write Buffer I/O error on dev loop0, logical block 9, lost async page write random: crng init done INFO: task syz-executor3:23174 blocked for more than 120 seconds. Not tainted 4.16.0-rc7+ #281 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D20032 23174 13872 0x20020004 Call Trace: context_switch kernel/sched/core.c:2862 [inline] __schedule+0x8fb/0x1ec0 kernel/sched/core.c:3440 schedule+0xf5/0x430 kernel/sched/core.c:3499 io_schedule+0x1c/0x70 kernel/sched/core.c:5115 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_range mm/filemap.c:558 [inline] filemap_write_and_wait_range+0x74/0xc0 mm/filemap.c:659 generic_file_read_iter+0x409/0x28e0 mm/filemap.c:2334 blkdev_read_iter+0x105/0x170 fs/block_dev.c:1928 call_read_iter include/linux/fs.h:1776 [inline] generic_file_splice_read+0x3f9/0x7b0 fs/splice.c:307 do_splice_to+0x10a/0x160 fs/splice.c:880 splice_direct_to_actor+0x242/0x820 fs/splice.c:952 do_splice_direct+0x29b/0x3c0 fs/splice.c:1061 do_sendfile+0x5c9/0xe80 fs/read_write.c:1413 C_SYSC_sendfile fs/read_write.c:1489 [inline] compat_SyS_sendfile+0xea/0x1a0 fs/read_write.c:1478 do_syscall_32_irqs_on arch/x86/entry/common.c:330 [inline] do_fast_syscall_32+0x3ec/0xf9f arch/x86/entry/common.c:392 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7f46c99 RSP: 002b:00000000f769d09c EFLAGS: 00000286 ORIG_RAX: 00000000000000bb RAX: ffffffffffffffda RBX: 0000000000000013 RCX: 0000000000000013 RDX: 0000000020000080 RSI: 0000000002000004 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/u4:0/5: #0: ((wq_completion)"writeback"){+.+.}, at: [<00000000d67eb335>] work_static include/linux/workqueue.h:198 [inline] #0: ((wq_completion)"writeback"){+.+.}, at: [<00000000d67eb335>] set_work_data kernel/workqueue.c:619 [inline] #0: ((wq_completion)"writeback"){+.+.}, at: [<00000000d67eb335>] set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: ((wq_completion)"writeback"){+.+.}, at: [<00000000d67eb335>] process_one_work+0xb12/0x1bb0 kernel/workqueue.c:2084 #1: ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: [<0000000025b154ed>] process_one_work+0xb89/0x1bb0 kernel/workqueue.c:2088 #2: (&type->s_umount_key#33){++++}, at: [<00000000acd1e72d>] trylock_super+0x20/0x100 fs/super.c:395 2 locks held by khungtaskd/868: #0: (rcu_read_lock){....}, at: [<00000000224e260f>] check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline] #0: (rcu_read_lock){....}, at: [<00000000224e260f>] watchdog+0x1c5/0xd60 kernel/hung_task.c:249 #1: (tasklist_lock){.+.?}, at: [<00000000c0944745>] debug_show_all_locks+0xd3/0x3d0 kernel/locking/lockdep.c:4470 2 locks held by getty/4414: #0: (&tty->ldisc_sem){++++}, at: [<0000000058ce2b1b>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000b27ebcc9>] n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4415: #0: (&tty->ldisc_sem){++++}, at: [<0000000058ce2b1b>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000b27ebcc9>] n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4416: #0: (&tty->ldisc_sem){++++}, at: [<0000000058ce2b1b>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000b27ebcc9>] n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4417: #0: (&tty->ldisc_sem){++++}, at: [<0000000058ce2b1b>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000b27ebcc9>] n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4418: #0: (&tty->ldisc_sem){++++}, at: [<0000000058ce2b1b>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000b27ebcc9>] n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4419: #0: (&tty->ldisc_sem){++++}, at: [<0000000058ce2b1b>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000b27ebcc9>] n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4420: #0: (&tty->ldisc_sem){++++}, at: [<0000000058ce2b1b>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000b27ebcc9>] n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 1 lock held by syz-executor1/23158: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000010e661b>] iterate_bdevs+0xc8/0x260 fs/block_dev.c:2160 1 lock held by syz-executor5/23184: #0: (&bdev->bd_mutex){+.+.}, at: [<00000000ea362300>] __blkdev_get+0x176/0x13b0 fs/block_dev.c:1458 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 868 Comm: khungtaskd Not tainted 4.16.0-rc7+ #281 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+0x194/0x24d lib/dump_stack.c:53 nmi_cpu_backtrace+0x1d2/0x210 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+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:406 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.16.0-rc7+ #281 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__preempt_count_add arch/x86/include/asm/preempt.h:76 [inline] RIP: 0010:rcu_read_lock_sched_notrace include/linux/rcupdate.h:754 [inline] RIP: 0010:trace_softirq_raise include/trace/events/irq.h:156 [inline] RIP: 0010:__raise_softirq_irqoff kernel/softirq.c:443 [inline] RIP: 0010:raise_softirq_irqoff+0x220/0x320 kernel/softirq.c:417 RSP: 0018:ffff8801db207c90 EFLAGS: 00000083 RAX: 0000000000000000 RBX: 1ffff1003b640f93 RCX: dffffc0000000000 RDX: 1ffff1003b645a0a RSI: 1ffff1003b640fc5 RDI: 0000000000000007 RBP: ffff8801db207d60 R08: 1ffff1003b6459fd R09: ffff88021fff8008 R10: ffff88021fff8010 R11: ffff88021fff801d R12: 0000000000000007 R13: ffff8801db207d38 R14: ffff8801db207e68 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 0000000007a22001 CR4: 00000000001606f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: scheduler_ipi+0x50b/0x820 kernel/sched/core.c:1802 smp_reschedule_interrupt+0xe6/0x650 arch/x86/kernel/smp.c:277 reschedule_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:881 RIP: 0010:native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:54 RSP: 0018:ffffffff87a07c38 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff02 RAX: dffffc0000000000 RBX: 1ffffffff0f40f8a RCX: 0000000000000000 RDX: 1ffffffff0f59580 RSI: 0000000000000001 RDI: ffffffff87acac00 RBP: ffffffff87a07c38 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffffffff87a07cf0 R14: ffffffff883b4820 R15: 0000000000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:94 [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:437 start_kernel+0x7f1/0x819 init/main.c:717 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:239 Code: 89 f2 48 c1 ea 03 80 3c 02 00 0f 85 d4 00 00 00 4d 8b 3e 4d 85 ff 75 b6 65 ff 0d cc 38 be 7e e9 62 fe ff ff 65 ff 05 c0 38 be 7e <49> 8d 45 c0 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 48 01 d0