INFO: task kworker/u8:0:12 blocked for more than 144 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:0 state:D stack:21112 pid:12 tgid:12 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: writeback wb_workfn (flush-7:6) Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0x1522/0x51d0 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0x164/0x360 kernel/sched/core.c:6964 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7021 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776 hfsplus_find_init+0x168/0x2d0 fs/hfsplus/bfind.c:28 hfsplus_cat_write_inode+0x23e/0x810 fs/hfsplus/inode.c:625 write_inode fs/fs-writeback.c:1582 [inline] __writeback_single_inode+0x7e1/0x1230 fs/fs-writeback.c:1802 writeback_sb_inodes+0x92e/0x1940 fs/fs-writeback.c:2030 __writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2107 wb_writeback+0x459/0xad0 fs/fs-writeback.c:2218 wb_check_old_data_flush fs/fs-writeback.c:2322 [inline] wb_do_writeback fs/fs-writeback.c:2375 [inline] wb_workfn+0xaee/0xef0 fs/fs-writeback.c:2403 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xaec/0x17a0 kernel/workqueue.c:3340 worker_thread+0xda6/0x1360 kernel/workqueue.c:3421 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Showing all locks held in the system: 4 locks held by kworker/u8:0/12: #0: ffff888140a9a948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff888140a9a948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc90000117bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc90000117bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffff88807c4100e0 (&type->s_umount_key#55){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563 #3: ffff88805a0220b0 (&tree->tree_lock){+.+.}-{4:4}, at: hfsplus_find_init+0x168/0x2d0 fs/hfsplus/bfind.c:28 1 lock held by khungtaskd/32: #0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5579: #0: ffff88802f2120a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 1 lock held by syz-executor/17969: #0: ffffffff8e560c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #0: ffffffff8e560c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:956 2 locks held by dhcpcd/21040: #0: ffff888078249908 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #0: ffff888078249908 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release net/socket.c:661 [inline] #0: ffff888078249908 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1455 #1: ffffffff8e560c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #1: ffffffff8e560c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:956 6 locks held by kworker/u8:20/21388: 4 locks held by syz.6.4128/24202: 4 locks held by dhcpcd-run-hook/26629: #0: ffff8880b863a918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xa9/0x140 kernel/sched/core.c:647 #1: ffff8880b8724588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 #2: ffff8880b8724588 (psi_seq){-.-.}-{0:0}, at: psi_task_change+0xd4/0x340 kernel/sched/psi.c:919 #3: ffff8880b863a918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xa9/0x140 kernel/sched/core.c:647 5 locks held by cmp/26639: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 32 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 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:161 [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:346 [inline] watchdog+0xf90/0xfe0 kernel/hung_task.c:515 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 24202 Comm: syz.6.4128 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 RIP: 0010:delay_tsc+0x60/0xc0 arch/x86/lib/delay.c:79 Code: c1 e7 20 49 09 c7 4d 29 f7 49 39 df 73 53 bf 01 00 00 00 e8 22 fc fc f5 65 8b 05 8b 0e 5d 07 85 c0 74 1c f3 90 bf 01 00 00 00 6b fa fc f5 e8 76 77 01 00 39 c5 75 0e 0f 01 f9 66 90 eb bd e8 RSP: 0018:ffffc9000450eaf0 EFLAGS: 00000082 RAX: 0000000080000002 RBX: 0000000000000993 RCX: 0000000000000000 RDX: 00000000000003f2 RSI: ffffffff8c073ae0 RDI: 0000000000000001 RBP: 0000000000000001 R08: ffff888021f50237 R09: 1ffff110043ea046 R10: dffffc0000000000 R11: ffffffff8b95c150 R12: 1ffffffff34670a6 R13: 00000000ffffffff R14: 000003f24e3f3d99 R15: 0000000000000823 FS: 00007fb5a20956c0(0000) GS:ffff8881257f3000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f703e4254ac CR3: 000000005e40b000 CR4: 0000000000350ef0 Call Trace: udelay include/asm-generic/delay.h:62 [inline] wait_for_lsr+0x160/0x2f0 drivers/tty/serial/8250/8250_port.c:1967 fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3234 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3257 [inline] serial8250_console_write+0x1348/0x1ba0 drivers/tty/serial/8250/8250_port.c:3342 console_emit_next_record kernel/printk/printk.c:3129 [inline] console_flush_one_record kernel/printk/printk.c:3215 [inline] console_flush_all+0x718/0xb20 kernel/printk/printk.c:3289 __console_flush_and_unlock kernel/printk/printk.c:3319 [inline] console_unlock+0xd1/0x1c0 kernel/printk/printk.c:3359 vprintk_emit+0x485/0x560 kernel/printk/printk.c:2426 _printk+0xdd/0x130 kernel/printk/printk.c:2451 hfsplus_bnode_read_u16 fs/hfsplus/bnode.c:60 [inline] hfsplus_bnode_dump+0x189/0xa40 fs/hfsplus/bnode.c:362 hfsplus_brec_remove+0x617/0x700 fs/hfsplus/brec.c:229 __hfsplus_delete_attr+0x1e0/0x380 fs/hfsplus/attributes.c:299 hfsplus_delete_attr+0x256/0x3d0 fs/hfsplus/attributes.c:345 __hfsplus_setxattr+0x40e/0x2240 fs/hfsplus/xattr.c:344 hfsplus_setxattr+0x11e/0x180 fs/hfsplus/xattr.c:434 hfsplus_trusted_setxattr+0x40/0x60 fs/hfsplus/xattr_trusted.c:30 __vfs_setxattr+0x43c/0x480 fs/xattr.c:200 __vfs_setxattr_noperm+0x12d/0x660 fs/xattr.c:234 vfs_setxattr+0x16a/0x2e0 fs/xattr.c:321 do_setxattr fs/xattr.c:636 [inline] filename_setxattr+0x281/0x630 fs/xattr.c:665 path_setxattrat+0x3f3/0x430 fs/xattr.c:713 __do_sys_lsetxattr fs/xattr.c:754 [inline] __se_sys_lsetxattr fs/xattr.c:750 [inline] __x64_sys_lsetxattr+0xbf/0xe0 fs/xattr.c:750 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb5a119aeb9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fb5a2095028 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd RAX: ffffffffffffffda RBX: 00007fb5a1415fa0 RCX: 00007fb5a119aeb9 RDX: 0000200000000880 RSI: 00002000000000c0 RDI: 0000200000000280 RBP: 00007fb5a1208c1f R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000fe37 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb5a1416038 R14: 00007fb5a1415fa0 R15: 00007fff672c92f8