INFO: task kworker/0:1:14 blocked for more than 145 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:1 state:D stack:22784 pid:14 ppid:2 flags:0x00004000 Workqueue: events_long flush_old_commits Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6696 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x555/0xaf0 kernel/locking/mutex.c:747 reiserfs_write_lock+0x75/0xd0 fs/reiserfs/lock.c:27 reiserfs_sync_fs fs/reiserfs/super.c:76 [inline] flush_old_commits+0x1de/0x2f0 fs/reiserfs/super.c:111 process_one_work+0x898/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 INFO: task syz.3.751:8512 blocked for more than 146 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.751 state:D stack:27872 pid:8512 ppid:4270 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6696 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x555/0xaf0 kernel/locking/mutex.c:747 reiserfs_write_lock+0x75/0xd0 fs/reiserfs/lock.c:27 reiserfs_lookup+0x137/0x420 fs/reiserfs/namei.c:364 lookup_one_qstr_excl+0x10e/0x240 fs/namei.c:1613 filename_create+0x21e/0x450 fs/namei.c:3885 do_symlinkat+0xb9/0x3f0 fs/namei.c:4498 __do_sys_symlinkat fs/namei.c:4525 [inline] __se_sys_symlinkat fs/namei.c:4522 [inline] __x64_sys_symlinkat+0x95/0xa0 fs/namei.c:4522 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fb3f198f749 RSP: 002b:00007fb3f27df038 EFLAGS: 00000246 ORIG_RAX: 000000000000010a RAX: ffffffffffffffda RBX: 00007fb3f1be6180 RCX: 00007fb3f198f749 RDX: 0000200000000340 RSI: 0000000000000005 RDI: 0000200000000440 RBP: 00007fb3f1a13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb3f1be6218 R14: 00007fb3f1be6180 R15: 00007ffece472648 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8c92bab0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8c92c2d0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 4 locks held by kworker/0:1/14: #0: ffff888017471138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #1: ffffc90000137d00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #2: ffff888078cd00e0 (&type->s_umount_key#73){++++}-{3:3}, at: flush_old_commits+0xc8/0x2f0 fs/reiserfs/super.c:97 #3: ffff888023e40090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x75/0xd0 fs/reiserfs/lock.c:27 1 lock held by khungtaskd/28: #0: ffffffff8c92b120 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] ffffffff8c92b120 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] ffffffff8c92b120 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513 2 locks held by getty/4024: #0: ffff88802faf5098 (&tty->ldisc_sem){++++}-{0:0} , at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc9000327b2f0 ( &ldata->atomic_read_lock ){+.+.}-{3:3} , at: n_tty_read+0x41b/0x1380 drivers/tty/n_tty.c:2198 5 locks held by kworker/0:19/8181: #0: ffff88801d2a8538 ( (wq_completion)usb_hub_wq ){+.+.}-{0:0} , at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #1: ffffc90003d37d00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #2: ffff888145ffe190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:840 [inline] #2: ffff888145ffe190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1a7/0x54e0 drivers/usb/core/hub.c:5845 #3: ffff888028b7f4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3200 [inline] #3: ffff888028b7f4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5413 [inline] #3: ffff888028b7f4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5657 [inline] #3: ffff888028b7f4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5817 [inline] #3: ffff888028b7f4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x21bd/0x54e0 drivers/usb/core/hub.c:5899 #4: ffff8880286ef168 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5414 [inline] #4: ffff8880286ef168 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5657 [inline] #4: ffff8880286ef168 (hcd->address0_mutex){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5817 [inline] #4: ffff8880286ef168 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_event+0x21ee/0x54e0 drivers/usb/core/hub.c:5899 4 locks held by syz.3.751/8495: 3 locks held by syz.3.751/8512: #0: ffff888078cd0460 ( sb_writers #23 ){.+.+}-{0:0} , at: mnt_want_write+0x3d/0x90 fs/namespace.c:402 #1: ffff888054f3b7e0 ( &type->i_mutex_dir_key #20 /1 ){+.+.}-{3:3} , at: inode_lock_nested include/linux/fs.h:793 [inline] , at: filename_create+0x1f2/0x450 fs/namei.c:3884 #2: ffff888023e40090 ( &sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x75/0xd0 fs/reiserfs/lock.c:27 2 locks held by syz.4.806/8880: #0: ffff888078cd00e0 ( &type->s_umount_key#73 ){++++}-{3:3}, at: iterate_supers+0xa4/0x1d0 fs/super.c:755 #1: ffff888023e40090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x75/0xd0 fs/reiserfs/lock.c:27 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 nmi_cpu_backtrace+0x3f4/0x470 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xeee/0xf30 kernel/hung_task.c:377 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 8495 Comm: syz.3.751 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline] RIP: 0010:static_key_false include/linux/jump_label.h:207 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:147 [inline] RIP: 0010:wrmsr arch/x86/include/asm/msr.h:254 [inline] RIP: 0010:native_apic_msr_write+0x35/0x50 arch/x86/include/asm/apic.h:206 Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 89 f6 31 d2 e9 7f e8 f7 02 66 2e 0f 1f 84 00 00 00 00 00 RSP: 0018:ffffc900001e0e38 EFLAGS: 00000046 RAX: 000000000008d5e5 RBX: 000000000008d5e5 RCX: 0000000000000838 RDX: 0000000000000000 RSI: 000000000008d5e5 RDI: 0000000000000838 RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff1bfe1c6 R10: fffffbfff1bfe1c6 R11: 1ffffffff1bfe1c5 R12: dffffc0000000000 R13: 0000000010005c46 R14: ffffffff8c3d8b40 R15: dffffc0000000000 FS: 00007fb3f28216c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f37983b7198 CR3: 000000001dff5000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: apic_write arch/x86/include/asm/apic.h:394 [inline] lapic_next_event+0x5b/0x70 arch/x86/kernel/apic/apic.c:478 clockevents_program_event+0x1bc/0x310 kernel/time/clockevents.c:334 hrtimer_interrupt+0x59d/0x9c0 kernel/time/hrtimer.c:1886 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline] __sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:1948 [inline] RIP: 0010:vprintk_emit+0x461/0x680 kernel/printk/printk.c:2302 Code: 85 8f 01 00 00 e8 af b9 1a 00 41 89 df 4d 85 f6 48 8b 1c 24 75 07 e8 9e b9 1a 00 eb 06 e8 97 b9 1a 00 fb 48 c7 c7 c0 f3 91 8c <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 37 db RSP: 0018:ffffc9000502ece0 EFLAGS: 00000246 RAX: ffffffff81662639 RBX: ffffffff816624e5 RCX: 0000000000080000 RDX: ffffc9000de59000 RSI: 000000000007ffff RDI: ffffffff8c91f3c0 RBP: ffffc9000502edd0 R08: dffffc0000000000 R09: fffffbfff211907b R10: fffffbfff211907b R11: 1ffffffff211907a R12: dffffc0000000000 R13: 1ffff92000a05da0 R14: 0000000000000200 R15: 0000000000000086 _printk+0xcc/0x110 kernel/printk/printk.c:2328 __reiserfs_warning+0x14e/0x1a0 fs/reiserfs/prints.c:290 reiserfs_read_bitmap_block+0x24c/0x730 fs/reiserfs/bitmap.c:1434 scan_bitmap_block+0x1ad/0xde0 fs/reiserfs/bitmap.c:164 scan_bitmap fs/reiserfs/bitmap.c:402 [inline] allocate_without_wrapping_disk fs/reiserfs/bitmap.c:1161 [inline] blocknrs_and_prealloc_arrays_from_search_start fs/reiserfs/bitmap.c:1274 [inline] reiserfs_allocate_blocknrs+0x367a/0x53b0 fs/reiserfs/bitmap.c:1375 _allocate_block fs/reiserfs/inode.c:-1 [inline] reiserfs_get_block+0x266f/0x3ef0 fs/reiserfs/inode.c:756 __block_write_begin_int+0x54b/0x1a70 fs/buffer.c:1991 reiserfs_write_begin+0x206/0x4c0 fs/reiserfs/inode.c:2775 generic_perform_write+0x2f7/0x5a0 mm/filemap.c:3862 __generic_file_write_iter+0x148/0x2a0 mm/filemap.c:3960 generic_file_write_iter+0xab/0x2e0 mm/filemap.c:3989 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x44c/0x960 fs/read_write.c:584 ksys_write+0x143/0x240 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fb3f198f749 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:00007fb3f2821038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fb3f1be5fa0 RCX: 00007fb3f198f749 RDX: 00000000ffffff6a RSI: 0000200000000000 RDI: 0000000000000007 RBP: 00007fb3f1a13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb3f1be6038 R14: 00007fb3f1be5fa0 R15: 00007ffece472648