INFO: task kworker/0:3:1191 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:3 state:D stack:24528 pid:1191 ppid:2 flags:0x00004000 Workqueue: events_long flush_old_commits Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x14d2/0x44d0 kernel/sched/core.c:6700 schedule+0xbd/0x170 kernel/sched/core.c:6774 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6833 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x6b7/0xcc0 kernel/locking/mutex.c:747 reiserfs_write_lock+0x79/0xd0 fs/reiserfs/lock.c:27 reiserfs_sync_fs fs/reiserfs/super.c:76 [inline] flush_old_commits+0x1e2/0x2f0 fs/reiserfs/super.c:111 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 INFO: task syz.0.25:5961 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.25 state:D stack:25032 pid:5961 ppid:5879 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x14d2/0x44d0 kernel/sched/core.c:6700 schedule+0xbd/0x170 kernel/sched/core.c:6774 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6833 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x6b7/0xcc0 kernel/locking/mutex.c:747 reiserfs_write_lock_nested+0x60/0xd0 fs/reiserfs/lock.c:78 reiserfs_mutex_lock_safe fs/reiserfs/reiserfs.h:814 [inline] lock_journal fs/reiserfs/journal.c:534 [inline] do_journal_end+0x3ba/0x4860 fs/reiserfs/journal.c:4032 reiserfs_create+0x5ec/0x680 fs/reiserfs/namei.c:693 lookup_open fs/namei.c:3496 [inline] open_last_lookups fs/namei.c:3564 [inline] path_openat+0x1277/0x3190 fs/namei.c:3794 do_filp_open+0x1c5/0x3d0 fs/namei.c:3824 do_sys_openat2+0x12c/0x1c0 fs/open.c:1421 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x139/0x160 fs/open.c:1447 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f417ad8f749 RSP: 002b:00007f417bb7e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f417afe6090 RCX: 00007f417ad8f749 RDX: 000000000000275a RSI: 0000200000000140 RDI: ffffffffffffff9c RBP: 00007f417ae13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f417afe6128 R14: 00007f417afe6090 R15: 00007ffdb5672c78 Showing all locks held in the system: 4 locks held by kworker/0:0/8: #0: ffff88802c4e6d38 ((wq_completion)reiserfs/loop2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff88802c4e6d38 ((wq_completion)reiserfs/loop2){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc900000d7d00 ((work_completion)(&(&journal->j_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc900000d7d00 ((work_completion)(&(&journal->j_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #2: ffff888026558490 (&jl->j_commit_mutex){+.+.}-{3:3}, at: reiserfs_mutex_lock_safe fs/reiserfs/reiserfs.h:813 [inline] #2: ffff888026558490 (&jl->j_commit_mutex){+.+.}-{3:3}, at: flush_commit_list+0x6c8/0x1d80 fs/reiserfs/journal.c:1007 #3: ffff88801c70b090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock_nested+0x60/0xd0 fs/reiserfs/lock.c:78 4 locks held by kworker/0:1/9: #0: ffff888017871138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888017871138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc900000e7d00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc900000e7d00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #2: ffff888020c8a0e0 (&type->s_umount_key#26){++++}-{3:3}, at: flush_old_commits+0xcc/0x2f0 fs/reiserfs/super.c:97 #3: ffff88807c136090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x79/0xd0 fs/reiserfs/lock.c:27 1 lock held by khungtaskd/29: #0: ffffffff8cd2ffa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8cd2ffa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8cd2ffa0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 4 locks held by kworker/0:2/788: #0: ffff888017871138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888017871138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc90003b67d00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc90003b67d00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #2: ffff88802d5180e0 (&type->s_umount_key#26){++++}-{3:3}, at: flush_old_commits+0xcc/0x2f0 fs/reiserfs/super.c:97 #3: ffff88801c70b090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x79/0xd0 fs/reiserfs/lock.c:27 4 locks held by kworker/0:3/1191: #0: ffff888017871138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888017871138 ((wq_completion)events_long){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc90004bbfd00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc90004bbfd00 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #2: ffff88807ece40e0 (&type->s_umount_key#26){++++}-{3:3}, at: flush_old_commits+0xcc/0x2f0 fs/reiserfs/super.c:97 #3: ffff8880312a0090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x79/0xd0 fs/reiserfs/lock.c:27 2 locks held by getty/5528: #0: ffff88803131a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217 3 locks held by syz.0.25/5959: 4 locks held by syz.0.25/5961: #0: ffff88807ece4418 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:412 #1: ffff888078691d70 (&type->i_mutex_dir_key#8){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline] #1: ffff888078691d70 (&type->i_mutex_dir_key#8){+.+.}-{3:3}, at: open_last_lookups fs/namei.c:3561 [inline] #1: ffff888078691d70 (&type->i_mutex_dir_key#8){+.+.}-{3:3}, at: path_openat+0x7c6/0x3190 fs/namei.c:3794 #2: ffffc900035e90f0 (&journal->j_mutex){+.+.}-{3:3}, at: reiserfs_mutex_lock_safe fs/reiserfs/reiserfs.h:813 [inline] #2: ffffc900035e90f0 (&journal->j_mutex){+.+.}-{3:3}, at: lock_journal fs/reiserfs/journal.c:534 [inline] #2: ffffc900035e90f0 (&journal->j_mutex){+.+.}-{3:3}, at: do_journal_end+0x3b0/0x4860 fs/reiserfs/journal.c:4032 #3: ffff8880312a0090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock_nested+0x60/0xd0 fs/reiserfs/lock.c:78 3 locks held by syz.1.27/5997: 3 locks held by syz.2.54/6133: 3 locks held by syz.3.89/6303: 3 locks held by syz.3.89/6305: #0: ffff88807be82418 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:412 #1: ffff888071992410 (&type->i_mutex_dir_key#8){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline] #1: ffff888071992410 (&type->i_mutex_dir_key#8){+.+.}-{3:3}, at: open_last_lookups fs/namei.c:3561 [inline] #1: ffff888071992410 (&type->i_mutex_dir_key#8){+.+.}-{3:3}, at: path_openat+0x7c6/0x3190 fs/namei.c:3794 #2: ffff88801ea4e090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock_nested+0x60/0xd0 fs/reiserfs/lock.c:78 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 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+0x16c/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x39b/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf41/0xf80 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 6133 Comm: syz.2.54 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x82/0x90 kernel/kcov.c:315 Code: 8d 52 28 4d 39 ca 77 22 89 ff 89 f6 49 ff c0 4c 89 01 48 c7 44 11 08 05 00 00 00 48 89 7c 11 10 48 89 74 11 18 48 89 44 11 20 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 48 8b 04 24 RSP: 0018:ffffc90004cfeb58 EFLAGS: 00000293 RAX: ffffffff82227bdc RBX: 0000000000001014 RCX: 0000000000000000 RDX: ffff8880246c8000 RSI: 0000000000000000 RDI: 0000000000000010 RBP: ffffc90004cfeca0 R08: 0000000000000000 R09: 00000000ffffffff R10: 0000000000000070 R11: 0000000000000000 R12: ffff88802c1d0030 R13: 0000000000000000 R14: 0000000000000000 R15: 1ffff1100583a006 FS: 00007effe82b26c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc7eba33000 CR3: 0000000023763000 CR4: 00000000003506f0 Call Trace: get_num_ver+0x43c/0xfe0 fs/reiserfs/fix_node.c:475 ip_check_balance fs/reiserfs/fix_node.c:1523 [inline] check_balance fs/reiserfs/fix_node.c:2083 [inline] fix_nodes+0x2854/0x82e0 fs/reiserfs/fix_node.c:2636 reiserfs_paste_into_item+0x5ce/0x7f0 fs/reiserfs/stree.c:2128 reiserfs_get_block+0x1bd3/0x3ed0 fs/reiserfs/inode.c:1069 __block_write_begin_int+0x566/0x1ad0 fs/buffer.c:2124 reiserfs_write_begin+0x20a/0x4c0 fs/reiserfs/inode.c:2771 generic_perform_write+0x2fb/0x5b0 mm/filemap.c:4031 generic_file_write_iter+0xaf/0x2e0 mm/filemap.c:4152 call_write_iter include/linux/fs.h:2018 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x43b/0x940 fs/read_write.c:584 ksys_pwrite64 fs/read_write.c:699 [inline] __do_sys_pwrite64 fs/read_write.c:709 [inline] __se_sys_pwrite64 fs/read_write.c:706 [inline] __x64_sys_pwrite64+0x195/0x220 fs/read_write.c:706 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7effe738f749 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:00007effe82b2038 EFLAGS: 00000246 ORIG_RAX: 0000000000000012 RAX: ffffffffffffffda RBX: 00007effe75e5fa0 RCX: 00007effe738f749 RDX: 0000000000000001 RSI: 000020000001f900 RDI: 0000000000000005 RBP: 00007effe7413f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000008000c63 R11: 0000000000000246 R12: 0000000000000000 R13: 00007effe75e6038 R14: 00007effe75e5fa0 R15: 00007fff3d6a9e98