INFO: task syz.2.71:6365 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.71 state:D stack:24296 pid:6365 tgid:6364 ppid:5829 task_flags:0x400140 flags:0x00080003 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x16f3/0x4c20 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 schedule_timeout+0x9a/0x270 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+0x2bf/0x5d0 kernel/sched/completion.c:153 f2fs_issue_checkpoint+0x382/0x610 fs/f2fs/checkpoint.c:-1 f2fs_do_sync_file+0x86c/0x1860 fs/f2fs/file.c:352 generic_write_sync include/linux/fs.h:3045 [inline] f2fs_file_write_iter+0x756/0x2480 fs/f2fs/file.c:5266 do_iter_readv_writev+0x635/0x8d0 fs/read_write.c:-1 vfs_writev+0x323/0x970 fs/read_write.c:1057 do_pwritev fs/read_write.c:1153 [inline] __do_sys_pwritev2 fs/read_write.c:1211 [inline] __se_sys_pwritev2+0x17c/0x2a0 fs/read_write.c:1202 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2a0115eec9 RSP: 002b:00007f29ff3be038 EFLAGS: 00000246 ORIG_RAX: 0000000000000148 RAX: ffffffffffffffda RBX: 00007f2a013b5fa0 RCX: 00007f2a0115eec9 RDX: 0000000000000001 RSI: 00002000000001c0 RDI: 0000000000000004 RBP: 00007f2a011e1f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000e7b R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2a013b6038 R14: 00007f2a013b5fa0 R15: 00007ffe6f335cb8 Showing all locks held in the system: 1 lock held by khungtaskd/38: #0: ffffffff8d3aa400 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8d3aa400 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8d3aa400 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:3/57: #0: ffff88814046a938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff88814046a938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc9000123fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc9000123fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffff8880331780d0 (&type->s_umount_key#67){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:562 2 locks held by getty/5577: #0: ffff88823bf340a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e832e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1400 drivers/tty/n_tty.c:2222 3 locks held by kworker/1:4/5805: 2 locks held by syz-executor/5814: 1 lock held by udevd/5865: 1 lock held by udevd/5969: 1 lock held by syz.2.71/6365: #0: ffff888033178480 (sb_writers#24){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3110 [inline] #0: ffff888033178480 (sb_writers#24){.+.+}-{0:0}, at: vfs_writev+0x28e/0x970 fs/read_write.c:1055 4 locks held by f2fs_ckpt-7:2/6392: 3 locks held by syz.4.306/7888: 1 lock held by syz.1.309/7868: #0: ffff8880321e20d0 (&type->s_umount_key#68/1){+.+.}-{4:4}, at: alloc_super+0x1ba/0x9a0 fs/super.c:344 2 locks held by syz.5.307/7870: 1 lock held by syz.3.308/7900: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline] watchdog+0xf60/0xfa0 kernel/hung_task.c:495 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5174 Comm: klogd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:switch_mm_irqs_off+0x127/0x7a0 arch/x86/mm/tlb.c:825 Code: 83 fd 04 00 00 41 f7 c7 00 08 00 00 0f 85 01 05 00 00 41 8d 4f 01 0f b7 c9 48 09 c8 49 39 c4 0f 85 f0 05 00 00 80 7c 24 28 00 <74> 08 65 c6 05 df 99 0d 10 00 49 39 dd 48 89 5c 24 30 0f 84 38 01 RSP: 0018:ffffc90003c0f560 EFLAGS: 00000046 RAX: 0000000035164000 RBX: ffff88803533a280 RCX: ffff8880355a8000 RDX: 0000000040000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90003c0f630 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffed100699e471 R12: 0000000035164000 R13: ffff888034cf2280 R14: ffff888034dc0000 R15: 0000000000000000 FS: 00007f2977b21c80(0000) GS:ffff888127120000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f44c8167000 CR3: 0000000035164000 CR4: 00000000003526f0 Call Trace: context_switch kernel/sched/core.c:5309 [inline] __schedule+0x10bf/0x4c20 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75 unix_wait_for_peer+0x1e9/0x2e0 net/unix/af_unix.c:1639 unix_dgram_sendmsg+0xb7a/0x1850 net/unix/af_unix.c:2273 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:742 __sys_sendto+0x3c7/0x520 net/socket.c:2244 __do_sys_sendto net/socket.c:2251 [inline] __se_sys_sendto net/socket.c:2247 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2247 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2977c71407 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:00007ffc26dc7950 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f2977b21c80 RCX: 00007f2977c71407 RDX: 0000000000000047 RSI: 00007ffc26dc7a90 RDI: 0000000000000003 RBP: 00007ffc26dc7ec0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000004000 R11: 0000000000000202 R12: 00007ffc26dc7ed8 R13: 00007ffc26dc7a90 R14: 000000000000002c R15: 00007ffc26dc7a90