INFO: task syz.1.40:6044 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.40 state:D stack:24616 pid:6044 tgid:6043 ppid:5590 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5504 [inline] __schedule+0x16dc/0x5500 kernel/sched/core.c:7228 __schedule_loop kernel/sched/core.c:7307 [inline] schedule+0x164/0x360 kernel/sched/core.c:7322 schedule_timeout+0xc0/0x2c0 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common kernel/sched/completion.c:121 [inline] wait_for_common kernel/sched/completion.c:132 [inline] wait_for_completion+0x2ca/0x5e0 kernel/sched/completion.c:153 f2fs_issue_checkpoint+0x550/0x6f0 fs/f2fs/checkpoint.c:-1 f2fs_do_sync_file+0xcd6/0x1960 fs/f2fs/file.c:362 vfs_fsync_range fs/sync.c:186 [inline] vfs_fsync fs/sync.c:200 [inline] do_fsync fs/sync.c:211 [inline] __do_sys_fdatasync fs/sync.c:221 [inline] __se_sys_fdatasync fs/sync.c:219 [inline] __x64_sys_fdatasync+0xbc/0x110 fs/sync.c:219 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5667cfce59 RSP: 002b:00007f5665f4e028 EFLAGS: 00000246 ORIG_RAX: 000000000000004b RAX: ffffffffffffffda RBX: 00007f5667f75fa0 RCX: 00007f5667cfce59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000007 RBP: 00007f5667d92e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f5667f76038 R14: 00007f5667f75fa0 R15: 00007ffe634dc2e8 INFO: lockdep is turned off. NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline] watchdog+0xfd7/0x1030 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 8370 Comm: udevd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:__update_load_avg_se+0x5ff/0xbd0 include/linux/math64.h:-1 Code: 80 94 00 48 be 00 00 00 00 00 fc ff df 4d 0f af 3e 41 89 ec 4c 89 f8 48 c1 e8 20 74 14 4c 89 f8 31 d2 49 f7 f4 49 89 c6 eb 12 <31> c0 e9 41 01 00 00 44 89 f8 31 d2 41 f7 f4 41 89 c6 48 8d bb 20 RSP: 0018:ffffc90004f7ec00 EFLAGS: 00000047 RAX: 00000036900fa000 RBX: ffff88801cfe0180 RCX: dffffc0000000000 RDX: ffff88801cfe0080 RSI: dffffc0000000000 RDI: ffff88801cfe00d8 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffffff81971450 R12: 1ffff110039fc030 R13: 0000000000000000 R14: 0000000000000339 R15: 0000000000000000 FS: 00007f054ea10880(0000) GS:ffff888126144000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f054e0bf000 CR3: 000000005d006000 CR4: 00000000003526f0 Call Trace: update_load_avg+0x1ae/0x1950 kernel/sched/fair.c:5652 set_next_entity kernel/sched/fair.c:6338 [inline] set_next_task_fair+0x116/0xce0 kernel/sched/fair.c:15045 set_next_task kernel/sched/sched.h:2745 [inline] sched_change_end+0x285/0x600 kernel/sched/core.c:11242 migrate_disable_switch kernel/sched/core.c:2465 [inline] __schedule+0x1879/0x5500 kernel/sched/core.c:7083 preempt_schedule_notrace+0x57/0x90 kernel/sched/core.c:7502 preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13 rcu_is_watching+0x7f/0xb0 kernel/rcu/tree.c:753 trace_lock_release include/trace/events/lock.h:68 [inline] lock_release+0x4b/0x3c0 kernel/locking/lockdep.c:5879 rt_spin_unlock+0x29/0x200 kernel/locking/spinlock_rt.c:80 spin_unlock_irq include/linux/spinlock_rt.h:122 [inline] loop_queue_work drivers/block/loop.c:859 [inline] loop_queue_rq+0xa48/0xb50 drivers/block/loop.c:1885 __blk_mq_issue_directly block/blk-mq.c:2694 [inline] blk_mq_request_issue_directly+0x3d7/0x6e0 block/blk-mq.c:2781 blk_mq_issue_direct+0x2a8/0x610 block/blk-mq.c:2802 blk_mq_dispatch_queue_requests+0x707/0x800 block/blk-mq.c:2877 blk_mq_flush_plug_list+0x428/0x540 block/blk-mq.c:2960 __blk_flush_plug+0x3ed/0x4d0 block/blk-core.c:1273 blk_finish_plug+0x5d/0x80 block/blk-core.c:1300 read_pages+0x3c2/0x5a0 mm/readahead.c:187 page_cache_ra_unbounded+0x679/0x8f0 mm/readahead.c:315 do_page_cache_ra mm/readahead.c:350 [inline] force_page_cache_ra+0x2fe/0x370 mm/readahead.c:380 filemap_get_pages+0x47a/0x1e30 mm/filemap.c:2705 filemap_read+0x429/0x11e0 mm/filemap.c:2815 blkdev_read_iter+0x2f8/0x430 block/fops.c:830 new_sync_read fs/read_write.c:493 [inline] vfs_read+0x59e/0xa90 fs/read_write.c:574 ksys_read+0x156/0x270 fs/read_write.c:716 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f054eafe407 Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007ffe56578de0 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f054ea10880 RCX: 00007f054eafe407 RDX: 0000000000000200 RSI: 00007f054e0be000 RDI: 0000000000000009 RBP: 000055f7f2d6c050 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000 R13: 0000000000fe0200 R14: 000055f7f2d6e1f8 R15: 00007f054f25439c