INFO: task syz.6.140:7225 blocked for more than 143 seconds. Not tainted 6.15.0-rc3-syzkaller-00032-ga79be02bba5c #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.6.140 state:D stack:24360 pid:7225 tgid:7223 ppid:6062 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1b33/0x51f0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x163/0x360 kernel/sched/core.c:6860 schedule_timeout+0xb1/0x2b0 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion+0x32f/0x600 kernel/sched/completion.c:148 f2fs_issue_checkpoint+0x420/0x5a0 fs/f2fs/checkpoint.c:1886 f2fs_do_sync_file+0xaac/0x1b00 fs/f2fs/file.c:330 generic_write_sync include/linux/fs.h:2976 [inline] f2fs_file_write_iter+0x7d5/0x2560 fs/f2fs/file.c:5189 new_sync_write fs/read_write.c:591 [inline] vfs_write+0x70f/0xd10 fs/read_write.c:684 ksys_write+0x19d/0x2d0 fs/read_write.c:736 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fce3a38e969 RSP: 002b:00007fce381f6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fce3a5b5fa0 RCX: 00007fce3a38e969 RDX: 000000000000da00 RSI: 0000200000000400 RDI: 0000000000000004 RBP: 00007fce3a410ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fce3a5b5fa0 R15: 00007ffd1e5d87f8 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6764 3 locks held by kworker/u8:7/1163: #0: ffff8880311c3148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff8880311c3148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc90003d9fc60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90003d9fc60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffffffff900eb548 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff900eb548 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x110/0x16a0 net/ipv6/addrconf.c:4195 2 locks held by getty/5582: #0: ffff88814d7240a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036db2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5bb/0x1700 drivers/tty/n_tty.c:2222 3 locks held by kworker/u8:8/6203: #0: ffff88801e6bb148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801e6bb148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc90003c5fc60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90003c5fc60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffff88807d7c60e0 (&type->s_umount_key#53){++++}-{4:4}, at: super_trylock_shared+0x22/0xf0 fs/super.c:562 3 locks held by kworker/1:8/6353: #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc90002ea7c60 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90002ea7c60 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffff88802870e240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x316/0x3f10 drivers/net/netdevsim/fib.c:1490 2 locks held by syz.6.140/7225: #0: ffff888034091438 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x247/0x310 fs/file.c:1213 #1: ffff88807d7c6420 (sb_writers#13){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline] #1: ffff88807d7c6420 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x23f/0xd10 fs/read_write.c:680 3 locks held by f2fs_ckpt-7:6/7253: 2 locks held by kworker/u8:9/8122: 2 locks held by syz.9.215/8291: #0: ffff88807d7c60e0 (&type->s_umount_key#53){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88807d7c60e0 (&type->s_umount_key#53){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120 #1: ffff8880257387d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline] #1: ffff8880257387d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x270/0xb50 fs/fs-writeback.c:2831 4 locks held by syz-executor/9131: 2 locks held by syz.6.301/9339: #0: ffff88807d7c60e0 (&type->s_umount_key#53){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88807d7c60e0 (&type->s_umount_key#53){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120 #1: ffff8880257387d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline] #1: ffff8880257387d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x270/0xb50 fs/fs-writeback.c:2831 5 locks held by syz-executor/9387: 1 lock held by syz-executor/9610: #0: ffffffff900eb548 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff900eb548 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x406/0x1c40 net/ipv4/devinet.c:979 5 locks held by syz.7.325/9727: 2 locks held by syz.3.326/9740: 2 locks held by udevadm/9785: 1 lock held by sed/9800: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc3-syzkaller-00032-ga79be02bba5c #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x4ab/0x4e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0x1058/0x10a0 kernel/hung_task.c:437 kthread+0x7b7/0x940 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 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: 7253 Comm: f2fs_ckpt-7:6 Not tainted 6.15.0-rc3-syzkaller-00032-ga79be02bba5c #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:F2FS_SB fs/f2fs/f2fs.h:1997 [inline] RIP: 0010:F2FS_I_SB fs/f2fs/f2fs.h:2002 [inline] RIP: 0010:f2fs_update_inode_page+0x4f/0x180 fs/f2fs/inode.c:754 Code: 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 b5 5e fe fd bd 38 06 00 00 48 03 2b 48 89 e8 48 c1 e8 03 42 80 3c 28 00 <74> 08 48 89 ef e8 97 5e fe fd 4c 8b 7d 00 4c 89 34 24 4d 8d 66 40 RSP: 0018:ffffc9000b3e7900 EFLAGS: 00000246 RAX: 1ffff1100faf8cc7 RBX: ffff888059b83eb8 RCX: ffff88801f3e5a00 RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffff888059b83e90 RBP: ffff88807d7c6638 R08: ffffffff84344373 R09: 1ffff1100b370866 R10: dffffc0000000000 R11: ffffed100b370867 R12: dffffc0000000000 R13: dffffc0000000000 R14: ffff888059b83e90 R15: ffff88805c72cae8 FS: 0000000000000000(0000) GS:ffff888124fcf000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffec62d6db8 CR3: 000000007d3cc000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: f2fs_sync_inode_meta fs/f2fs/checkpoint.c:1165 [inline] block_operations fs/f2fs/checkpoint.c:1273 [inline] f2fs_write_checkpoint+0xa44/0x1da0 fs/f2fs/checkpoint.c:1652 __write_checkpoint_sync fs/f2fs/checkpoint.c:1770 [inline] __checkpoint_and_complete_reqs+0xd8/0x3c0 fs/f2fs/checkpoint.c:1789 issue_checkpoint_thread+0xdb/0x270 fs/f2fs/checkpoint.c:1820 kthread+0x7b7/0x940 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245