INFO: task kworker/u8:16:6053 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:16 state:D stack:22056 pid:6053 tgid:6053 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: writeback wb_workfn (flush-7:2) Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x14bc/0x5000 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:776 hfsplus_find_init+0x168/0x2d0 fs/hfsplus/bfind.c:28 hfsplus_cat_write_inode+0x1e6/0x7a0 fs/hfsplus/inode.c:625 write_inode fs/fs-writeback.c:1582 [inline] __writeback_single_inode+0x7e1/0x1240 fs/fs-writeback.c:1802 writeback_sb_inodes+0x93a/0x1870 fs/fs-writeback.c:2030 __writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2107 wb_writeback+0x43f/0xaa0 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+0xad2/0xed0 fs/fs-writeback.c:2403 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 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: 6 locks held by kworker/0:1/10: #0: ffff88801ce93548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88801ce93548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340 #1: ffffc900000f7b80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc900000f7b80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340 #2: ffff88814437b198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #2: ffff88814437b198 (&dev->mutex){....}-{4:4}, at: hub_event+0x187/0x4ef0 drivers/usb/core/hub.c:5899 #3: ffff888056a73198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #3: ffff888056a73198 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0xf8/0x990 drivers/usb/core/hub.c:2336 #4: ffff88802a80d160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #4: ffff88802a80d160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1104 [inline] #4: ffff88802a80d160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x800 drivers/base/dd.c:1302 #5: ffffffff8df47538 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:956 5 locks held by kworker/u8:1/13: #0: ffff8880b863a918 (&rq->__lock ){-.-.}-{2:2} , at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:647 #1: ffff8880b8724588 ( psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 #2: ffff88807a188788 (&rdev->wiphy.mtx){+.+.}-{4:4} , at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:647 #3: ffffffff8df419e0 (rcu_read_lock){....}-{1:3} , at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] , at: rcu_read_lock include/linux/rcupdate.h:867 [inline] , at: ieee80211_sta_active_ibss+0xc3/0x330 net/mac80211/ibss.c:635 #4: ffffffff8df419e0 ( rcu_read_lock ){....}-{1:3} , at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] , at: rcu_read_lock include/linux/rcupdate.h:867 [inline] , at: class_rcu_constructor include/linux/rcupdate.h:1195 [inline] , at: unwind_next_frame+0xa5/0x2390 arch/x86/kernel/unwind_orc.c:479 1 lock held by khungtaskd/32: #0: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8df419e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5579: #0: ffff8880304760a0 ( &tty->ldisc_sem ){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000331e2f0 (&ldata->atomic_read_lock ){+.+.}-{4:4} , at: n_tty_read+0x449/0x1460 drivers/tty/n_tty.c:2211 4 locks held by kworker/u8:16/6053: #0: ffff8881416ea148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340 #1: ffffc90004fc7b80 ((work_completion)(&(&wb->dwork)->work) ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3233 [inline] , at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340 #2: ffff88807cd220e0 (&type->s_umount_key#49){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563 #3: ffff88804ed540b0 (&tree->tree_lock){+.+.}-{4:4}, at: hfsplus_find_init+0x168/0x2d0 fs/hfsplus/bfind.c:28 9 locks held by syz.2.298/7413: ============================================= NMI backtrace for cpu 1 CPU: 1 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 10/25/2025 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] __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+0xf95/0xfe0 kernel/hung_task.c:515 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 7413 Comm: syz.2.298 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:io_serial_out+0x7c/0xc0 drivers/tty/serial/8250/8250_port.c:407 Code: de a6 fc 44 89 f9 d3 e5 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 5c 30 0d fd 41 03 2e 89 d8 89 ea ee <5b> 41 5c 41 5e 41 5f 5d e9 a2 6e f5 fb cc 44 89 f9 80 e1 07 38 c1 RSP: 0018:ffffc90004a6ea70 EFLAGS: 00000006 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 00000000000003f9 RSI: 0000000000000000 RDI: 0000000000000020 RBP: 00000000000003f9 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: ffffffff851ad1e0 R12: dffffc0000000000 R13: dffffc0000000000 R14: ffffffff99bef280 R15: 0000000000000000 FS: 00007f7a7ac6e6c0(0000) GS:ffff888125e3a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8e2ce2eb48 CR3: 00000000309ee000 CR4: 0000000000350ef0 Call Trace: serial_out drivers/tty/serial/8250/8250.h:133 [inline] serial8250_clear_IER drivers/tty/serial/8250/8250_port.c:-1 [inline] serial8250_console_write+0x5f2/0x1ba0 drivers/tty/serial/8250/8250_port.c:3307 console_emit_next_record kernel/printk/printk.c:3129 [inline] console_flush_one_record kernel/printk/printk.c:3215 [inline] console_flush_all+0x745/0xb60 kernel/printk/printk.c:3289 __console_flush_and_unlock kernel/printk/printk.c:3319 [inline] console_unlock+0xbb/0x190 kernel/printk/printk.c:3359 vprintk_emit+0x4f8/0x5f0 kernel/printk/printk.c:2426 _printk+0xcf/0x120 kernel/printk/printk.c:2451 hfsplus_bnode_read_u16 fs/hfsplus/bnode.c:60 [inline] hfsplus_bnode_dump+0x16b/0xa00 fs/hfsplus/bnode.c:362 hfsplus_brec_remove+0x61c/0x700 fs/hfsplus/brec.c:229 __hfsplus_delete_attr+0x1d4/0x360 fs/hfsplus/attributes.c:299 hfsplus_delete_attr+0x239/0x3b0 fs/hfsplus/attributes.c:345 __hfsplus_setxattr+0x396/0x2170 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+0x16b/0x2f0 fs/xattr.c:321 do_setxattr fs/xattr.c:636 [inline] filename_setxattr+0x274/0x600 fs/xattr.c:665 path_setxattrat+0x364/0x3a0 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+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7a79d8f749 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f7a7ac6e038 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd RAX: ffffffffffffffda RBX: 00007f7a79fe5fa0 RCX: 00007f7a79d8f749 RDX: 0000200000000880 RSI: 00002000000000c0 RDI: 0000200000000280 RBP: 00007f7a79e13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000fe37 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7a79fe6038 R14: 00007f7a79fe5fa0 R15: 00007ffd99274a38