INFO: task kworker/u8:3:49 blocked for more than 143 seconds. Not tainted 6.16.0-syzkaller-10355-gf2d282e1dfb3 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:3 state:D stack:21000 pid:49 tgid:49 ppid:2 task_flags:0x4208160 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:0) Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e3/0x1340 kernel/locking/mutex.c:760 hfsplus_find_init+0x15a/0x1d0 fs/hfsplus/bfind.c:28 hfsplus_cat_write_inode+0x1e6/0x7a0 fs/hfsplus/inode.c:592 write_inode fs/fs-writeback.c:1525 [inline] __writeback_single_inode+0x6f1/0xff0 fs/fs-writeback.c:1745 writeback_sb_inodes+0x6c7/0x1010 fs/fs-writeback.c:1976 __writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2047 wb_writeback+0x44f/0xaf0 fs/fs-writeback.c:2158 wb_check_old_data_flush fs/fs-writeback.c:2262 [inline] wb_do_writeback fs/fs-writeback.c:2315 [inline] wb_workfn+0xaef/0xef0 fs/fs-writeback.c:2343 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e139e60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e139e60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e139e60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 4 locks held by kworker/u8:3/49: #0: ffff8881412ee948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff8881412ee948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc90000b97bc0 ( (work_completion)(&(&wb->dwork)->work) ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3212 [inline] , at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffff8880332b00e0 ( &type->s_umount_key #42 ){.+.+}-{4:4} , at: super_trylock_shared+0x20/0xf0 fs/super.c:563 #3: ffff8880792320b0 ( &tree->tree_lock){+.+.}-{4:4}, at: hfsplus_find_init+0x15a/0x1d0 fs/hfsplus/bfind.c:28 5 locks held by kworker/u8:4/61: #0: ffff8880b8739f58 ( &rq->__lock ){-.-.}-{2:2} , at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:636 #1: ffff8880b8724008 ( per_cpu_ptr(&psi_seq, cpu)){-.-.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] per_cpu_ptr(&psi_seq, cpu)){-.-.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8dfd2f50 (cpu_hotplug_lock){++++}-{0:0}, at: static_key_disable+0x12/0x20 kernel/jump_label.c:247 #3: ffffffff99c6aca8 ( &obj_hash[i].lock ){-.-.}-{2:2} , at: debug_object_activate+0xbb/0x420 lib/debugobjects.c:818 #4: ffffffff8dfe6308 ( text_mutex ){+.+.}-{4:4} , at: arch_jump_label_transform_apply+0x17/0x30 arch/x86/kernel/jump_label.c:145 2 locks held by getty/5605: #0: ffff88803031a0a0 ( &tty->ldisc_sem ){++++}-{0:0} , at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036c32f0 ( &ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 4 locks held by syz-executor384/5873: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-syzkaller-10355-gf2d282e1dfb3 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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:307 [inline] watchdog+0xf93/0xfe0 kernel/hung_task.c:470 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 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: 5873 Comm: syz-executor384 Not tainted 6.16.0-syzkaller-10355-gf2d282e1dfb3 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:kasan_check_range+0xd/0x2c0 mm/kasan/generic.c:188 Code: 0f 0b cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 55 41 57 41 56 41 55 41 54 <53> b0 01 48 85 f6 0f 84 ba 01 00 00 4c 8d 04 37 49 39 f8 0f 82 82 RSP: 0018:ffffc9000414eb30 EFLAGS: 00000056 RAX: 00000000ffffff01 RBX: ffffffff99dbe400 RCX: ffffffff819df6c1 RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc9000414eba0 RBP: ffffc9000414ec10 R08: ffffffff99dbe403 R09: 1ffffffff33b7c80 R10: dffffc0000000000 R11: fffffbfff33b7c81 R12: ffffffff99dbe410 R13: ffffffff99dbe408 R14: 1ffffffff33b7c82 R15: 1ffffffff33b7c81 FS: 0000555574d53380(0000) GS:ffff888125d5c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffcbbc35f19 CR3: 00000000714b1000 CR4: 0000000000350ef0 Call Trace: instrument_atomic_read_write include/linux/instrumented.h:96 [inline] atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1301 [inline] queued_spin_lock include/asm-generic/qspinlock.h:111 [inline] do_raw_spin_lock+0x121/0x290 kernel/locking/spinlock_debug.c:116 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline] _raw_spin_lock_irqsave+0xb3/0xf0 kernel/locking/spinlock.c:162 uart_port_lock_irqsave include/linux/serial_core.h:717 [inline] serial8250_console_write+0x17e/0x1ba0 drivers/tty/serial/8250/8250_port.c:3355 console_emit_next_record kernel/printk/printk.c:3138 [inline] console_flush_all+0x728/0xc40 kernel/printk/printk.c:3226 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0xc4/0x270 kernel/printk/printk.c:3325 vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450 _printk+0xcf/0x120 kernel/printk/printk.c:2475 hfsplus_bnode_read_u16 fs/hfsplus/bnode.c:101 [inline] hfsplus_bnode_dump+0x322/0x450 fs/hfsplus/bnode.c:403 hfsplus_brec_remove+0x480/0x550 fs/hfsplus/brec.c:229 __hfsplus_delete_attr+0x1d4/0x360 fs/hfsplus/attributes.c:299 hfsplus_delete_attr+0x231/0x2d0 fs/hfsplus/attributes.c:345 hfsplus_removexattr fs/hfsplus/xattr.c:796 [inline] __hfsplus_setxattr+0x768/0x1fe0 fs/hfsplus/xattr.c:279 hfsplus_setxattr+0x11e/0x180 fs/hfsplus/xattr.c:436 hfsplus_user_setxattr+0x40/0x60 fs/hfsplus/xattr_user.c:30 __vfs_removexattr+0x431/0x470 fs/xattr.c:518 __vfs_removexattr_locked+0x1ed/0x230 fs/xattr.c:553 vfs_removexattr+0x80/0x1b0 fs/xattr.c:575 removexattr fs/xattr.c:1023 [inline] filename_removexattr fs/xattr.c:1052 [inline] path_removexattrat+0x35d/0x690 fs/xattr.c:1088 __do_sys_removexattr fs/xattr.c:1100 [inline] __se_sys_removexattr fs/xattr.c:1097 [inline] __x64_sys_removexattr+0x62/0x70 fs/xattr.c:1097 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: 0033:0x7fd613ef9bd9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 17 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff6590fb28 EFLAGS: 00000246 ORIG_RAX: 00000000000000c5 RAX: ffffffffffffffda RBX: 0000200000000340 RCX: 00007fd613ef9bd9 RDX: ffffffffffffffb8 RSI: 0000200000000080 RDI: 0000200000000040 RBP: 0000200000000380 R08: 0000555574d544c0 R09: 0000555574d544c0 R10: 0000000000000000 R11: 0000000000000246 R12: 0030656c69662f2e R13: 00007fff6590fd78 R14: 431bde82d7b634db R15: 0000200000000390 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 3.116 msecs