INFO: task syz-executor.5:15605 blocked for more than 143 seconds. Not tainted 5.5.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D26664 15605 10077 0x00004004 Call Trace: context_switch kernel/sched/core.c:3385 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4081 schedule+0xdc/0x2b0 kernel/sched/core.c:4155 io_schedule+0x1c/0x70 kernel/sched/core.c:5799 wait_on_page_bit_common mm/filemap.c:1175 [inline] wait_on_page_bit+0x27c/0xa60 mm/filemap.c:1224 wait_on_page_writeback+0x1b2/0x4f0 mm/page-writeback.c:2822 __filemap_fdatawait_range+0x145/0x340 mm/filemap.c:526 file_write_and_wait_range+0x1ac/0x210 mm/filemap.c:786 __generic_file_fsync+0x79/0x200 fs/libfs.c:1000 fat_file_fsync+0x78/0x210 fs/fat/file.c:190 vfs_fsync_range+0x141/0x230 fs/sync.c:197 generic_write_sync include/linux/fs.h:2856 [inline] generic_file_write_iter+0x4ea/0x68e mm/filemap.c:3474 call_write_iter include/linux/fs.h:1902 [inline] new_sync_write+0x4d3/0x770 fs/read_write.c:483 __vfs_write+0xe1/0x110 fs/read_write.c:496 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/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a919 Code: 48 01 de 48 29 d9 e8 56 f8 ff ff 48 8b ac 24 00 80 00 00 48 81 c4 08 80 00 00 c3 e8 41 f6 ff ff e9 4c ff ff ff 48 8d bc 24 10 <80> 00 00 48 39 3b 75 8c 48 89 23 eb 87 cc cc cc cc cc cc cc cc cc RSP: 002b:00007f34f2892c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a919 RDX: 000000010000005c RSI: 00000000200015c0 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f34f28936d4 R13: 00000000004cbd0a R14: 00000000004e5aa0 R15: 00000000ffffffff INFO: task syz-executor.5:15611 blocked for more than 143 seconds. Not tainted 5.5.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D27088 15611 10077 0x00004004 Call Trace: context_switch kernel/sched/core.c:3385 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4081 schedule+0xdc/0x2b0 kernel/sched/core.c:4155 io_schedule+0x1c/0x70 kernel/sched/core.c:5799 wait_on_page_bit_common mm/filemap.c:1175 [inline] wait_on_page_bit+0x27c/0xa60 mm/filemap.c:1224 wait_on_page_writeback+0x1b2/0x4f0 mm/page-writeback.c:2822 __filemap_fdatawait_range+0x145/0x340 mm/filemap.c:526 filemap_fdatawait_range+0x26/0x40 mm/filemap.c:553 filemap_fdatawait include/linux/fs.h:2739 [inline] __writeback_single_inode+0x969/0x1400 fs/fs-writeback.c:1462 writeback_single_inode+0x2cf/0x440 fs/fs-writeback.c:1565 sync_inode fs/fs-writeback.c:2602 [inline] sync_inode_metadata+0xa8/0xe0 fs/fs-writeback.c:2622 __generic_file_fsync+0x169/0x200 fs/libfs.c:1011 fat_file_fsync+0x78/0x210 fs/fat/file.c:190 vfs_fsync_range+0x141/0x230 fs/sync.c:197 generic_write_sync include/linux/fs.h:2856 [inline] generic_file_write_iter+0x4ea/0x68e mm/filemap.c:3474 call_write_iter include/linux/fs.h:1902 [inline] new_sync_write+0x4d3/0x770 fs/read_write.c:483 __vfs_write+0xe1/0x110 fs/read_write.c:496 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/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a919 Code: 48 01 de 48 29 d9 e8 56 f8 ff ff 48 8b ac 24 00 80 00 00 48 81 c4 08 80 00 00 c3 e8 41 f6 ff ff e9 4c ff ff ff 48 8d bc 24 10 <80> 00 00 48 39 3b 75 8c 48 89 23 eb 87 cc cc cc cc cc cc cc cc cc RSP: 002b:00007f34f282fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a919 RDX: 000000010000005c RSI: 00000000200015c0 RDI: 0000000000000004 RBP: 000000000075c118 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f34f28306d4 R13: 00000000004cbd0a R14: 00000000004e5aa0 R15: 00000000ffffffff Showing all locks held in the system: 3 locks held by kworker/u4:2/102: #0: ffff8880ae837358 (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1215 [inline] #0: ffff8880ae837358 (&rq->lock){-.-.}, at: __schedule+0x232/0x1f90 kernel/sched/core.c:4029 #1: ffffffff899a5680 (rcu_read_lock){....}, at: __update_idle_core+0x45/0x3f0 kernel/sched/fair.c:5729 #2: ffff8880ae827258 (&base->lock){-.-.}, at: lock_timer_base+0x56/0x1b0 kernel/time/timer.c:936 2 locks held by kworker/u4:3/223: #0: ffff88821ad78128 ((wq_completion)writeback){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff88821ad78128 ((wq_completion)writeback){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff88821ad78128 ((wq_completion)writeback){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff88821ad78128 ((wq_completion)writeback){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff88821ad78128 ((wq_completion)writeback){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff88821ad78128 ((wq_completion)writeback){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff88821ad78128 ((wq_completion)writeback){+.+.}, at: process_one_work+0x88b/0x1740 kernel/workqueue.c:2235 #1: ffffc900012b7dc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0x8c1/0x1740 kernel/workqueue.c:2239 1 lock held by khungtaskd/1045: #0: ffffffff899a5680 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279 kernel/locking/lockdep.c:5334 2 locks held by getty/10030: #0: ffff8880a3044090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000176b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/10031: #0: ffff888099f86090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000175b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/10032: #0: ffff8880976f2090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000174b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/10033: #0: ffff8880a2202090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900016fb2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/10034: #0: ffff8880a0398090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000177b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/10035: #0: ffff888215797090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900011102e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/15628: #0: ffff8880a6b4c090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90000e902e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by syz-executor.5/15605: #0: ffff88809f5788e0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 #1: ffff88806f894428 (sb_writers#13){.+.+}, at: file_start_write include/linux/fs.h:2885 [inline] #1: ffff88806f894428 (sb_writers#13){.+.+}, at: vfs_write+0x485/0x5d0 fs/read_write.c:557 3 locks held by syz-executor.5/15611: #0: ffff888054358b60 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 #1: ffff88806f894428 (sb_writers#13){.+.+}, at: file_start_write include/linux/fs.h:2885 [inline] #1: ffff88806f894428 (sb_writers#13){.+.+}, at: vfs_write+0x485/0x5d0 fs/read_write.c:557 #2: ffff888045570c70 (&sb->s_type->i_mutex_key#22){++++}, at: inode_lock include/linux/fs.h:791 [inline] #2: ffff888045570c70 (&sb->s_type->i_mutex_key#22){++++}, at: __generic_file_fsync+0xb5/0x200 fs/libfs.c:1004 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1045 Comm: khungtaskd Not tainted 5.5.0-rc3-syzkaller #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+0x197/0x210 lib/dump_stack.c:118 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:205 [inline] watchdog+0xb11/0x10c0 kernel/hung_task.c:289 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 skipped: idling at native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60