INFO: task jfsCommit:129 blocked in I/O wait for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:jfsC[ 324.247098][ T39] task:jfsCommit state:D stack:26784 pid:129 tgid:129 ppid:2 task_flags:0x200040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x169e/0x54f0 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0x164/0x360 kernel/sched/core.c:7283 io_schedule+0x7f/0xd0 kernel/sched/core.c:8110 __lock_metapage fs/jfs/jfs_metapage.c:52 [inline] lock_metapage+0x1ff/0x400 fs/jfs/jfs_metapage.c:66 __get_metapage+0x49a/0xe20 fs/jfs/jfs_metapage.c:749 diIAGRead+0xce/0x140 fs/jfs/jfs_imap.c:2672 diFree+0x9dd/0x2ca0 fs/jfs/jfs_imap.c:959 jfs_evict_inode+0x331/0x440 fs/jfs/inode.c:162 evict+0x61e/0xb10 fs/inode.c:841 txLazyCommit fs/jfs/jfs_txnmgr.c:2666 [inline] jfs_lazycommit+0x3ef/0xa10 fs/jfs/jfs_txnmgr.c:2735 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task jfsCommit:130 blocked in I/O wait for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:jfsCommit state:D stack:27096 pid:130 tgid:130 ppid:2 task_flags:0x200040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x169e/0x54f0 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0x164/0x360 kernel/sched/core.c:7283 io_schedule+0x7f/0xd0 kernel/sched/core.c:8110 __lock_metapage fs/jfs/jfs_metapage.c:52 [inline] lock_metapage+0x1ff/0x400 fs/jfs/jfs_metapage.c:66 __get_metapage+0x49a/0xe20 fs/jfs/jfs_metapage.c:749 diIAGRead+0xce/0x140 fs/jfs/jfs_imap.c:2672 diFree+0x9dd/0x2ca0 fs/jfs/jfs_imap.c:959 jfs_evict_inode+0x331/0x440 fs/jfs/inode.c:162 evict+0x61e/0xb10 fs/inode.c:841 txLazyCommit fs/jfs/jfs_txnmgr.c:2666 [inline] jfs_lazycommit+0x3ef/0xa10 fs/jfs/jfs_txnmgr.c:2735 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 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/39: #0: ffffffff8dfc8180 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8dfc8180 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8dfc8180 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6777 2 locks held by jfsCommit/129: #0: ffff888038920900 (&(imap->im_aglock[index])){+.+.}-{4:4}, at: diFree+0x2e8/0x2ca0 fs/jfs/jfs_imap.c:889 #1: ffff888059d64ea8 (&jfs_ip->rdwrlock/1){.+.+}-{4:4}, at: diFree+0x306/0x2ca0 fs/jfs/jfs_imap.c:894 2 locks held by jfsCommit/130: #0: ffff88804c6c0900 (&(imap->im_aglock[index])){+.+.}-{4:4}, at: diFree+0x2e8/0x2ca0 fs/jfs/jfs_imap.c:889 #1: ffff88805b4d7548 (&jfs_ip->rdwrlock/1){.+.+}-{4:4}, at: diFree+0x306/0x2ca0 fs/jfs/jfs_imap.c:894 2 locks held by getty/5365: #0: ffff88803548b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003cc62e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211 2 locks held by syz-executor/6189: #0: ffff888038e040d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888038e040d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff888038e040d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e45a238 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1441 2 locks held by syz-executor/6192: #0: ffff88803a2340d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88803a2340d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88803a2340d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e45a238 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1441 2 locks held by syz-executor/6202: #0: ffff88805e0020d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805e0020d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88805e0020d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e45a238 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1441 2 locks held by syz-executor/6203: #0: ffff88803c4f40d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88803c4f40d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88803c4f40d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e45a238 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1441 1 lock held by syz-executor/6944: #0: ffff888024a780d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888024a780d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff888024a780d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 2 locks held by syz-executor/6951: #0: ffff88805ba520d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805ba520d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88805ba520d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e45a238 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1441 1 lock held by syz-executor/6957: #0: ffff88803a85c0d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88803a85c0d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88803a85c0d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 1 lock held by syz-executor/6961: #0: ffff88803300a0d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88803300a0d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88803300a0d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 1 lock held by syz-executor/6962: #0: ffff88802d9560d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88802d9560d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88802d9560d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 1 lock held by syz-executor/7532: #0: ffff8880369360d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff8880369360d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff8880369360d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 1 lock held by syz-executor/7699: #0: ffff88803f7ce480 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493 1 lock held by syz.5.171/8749: #0: ffffffff8dfc8180 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8dfc8180 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8dfc8180 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1181 [inline] #0: ffffffff8dfc8180 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xa6/0x2550 arch/x86/kernel/unwind_orc.c:495 3 locks held by syz.4.172/8755: #0: ffff88801b6b2480 (sb_writers#5){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2724 [inline] #0: ffff88801b6b2480 (sb_writers#5){.+.+}-{0:0}, at: vfs_write+0x22d/0xba0 fs/read_write.c:684 #1: ffff888033df7b08 (&sb->s_type->i_mutex_key#15){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #1: ffff888033df7b08 (&sb->s_type->i_mutex_key#15){+.+.}-{4:4}, at: shmem_file_write_iter+0x82/0x120 mm/shmem.c:3465 #2: ffff888033df77d8 (&info->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #2: ffff888033df77d8 (&info->lock){+.+.}-{3:3}, at: shmem_recalc_inode mm/shmem.c:443 [inline] #2: ffff888033df77d8 (&info->lock){+.+.}-{3:3}, at: shmem_alloc_and_add_folio mm/shmem.c:2033 [inline] #2: ffff888033df77d8 (&info->lock){+.+.}-{3:3}, at: shmem_get_folio_gfp+0xa63/0x1a80 mm/shmem.c:2564 2 locks held by syz.0.173/8759: #0: ffff88801b6b2480 (sb_writers#5){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2724 [inline] #0: ffff88801b6b2480 (sb_writers#5){.+.+}-{0:0}, at: vfs_write+0x22d/0xba0 fs/read_write.c:684 #1: ffff88803b2e8b00 (&sb->s_type->i_mutex_key#15){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #1: ffff88803b2e8b00 (&sb->s_type->i_mutex_key#15){+.+.}-{4:4}, at: shmem_file_write_iter+0x82/0x120 mm/shmem.c:3465 1 lock held by syz.2.174/8764: #0: ffff88804454dd08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310 1 lock held by cmp/8766: #0: ffff88803bffb7b0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:554 [inline] #0: ffff88803bffb7b0 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x237/0x4f0 mm/util.c:579 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 39 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 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:162 [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:353 [inline] watchdog+0xfd3/0x1030 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 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: 17 Comm: pr/legacy Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:io_serial_out+0x7c/0xc0 drivers/tty/serial/8250/8250_port.c:408 Code: db 86 fc 44 89 f9 d3 e5 49 83 ee 80 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 5c 65 f0 fc 41 03 2e 89 d8 89 ea ee <5b> 41 5c 41 5e 41 5f 5d e9 c7 3e ed 05 cc 44 89 f9 80 e1 07 38 c1 RSP: 0018:ffffc90000167a30 EFLAGS: 00000202 RAX: 0000000000000031 RBX: 0000000000000031 RCX: 0000000000000000 RDX: 00000000000003f8 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00000000000003f8 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffffff853dbb50 R12: dffffc0000000000 R13: 0000000000000001 R14: ffffffff99b668a0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88812602a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fffa0e41fd8 CR3: 00000000369e2000 CR4: 00000000003526f0 Call Trace: serial_port_out include/linux/serial_core.h:811 [inline] serial8250_console_putchar drivers/tty/serial/8250/8250_port.c:3217 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:-1 [inline] serial8250_console_write+0x12e1/0x1b90 drivers/tty/serial/8250/8250_port.c:3357 console_emit_next_record kernel/printk/printk.c:3163 [inline] console_flush_one_record+0x68b/0xb90 kernel/printk/printk.c:3269 legacy_kthread_func+0x1b6/0x250 kernel/printk/printk.c:3712 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 ---------------- Code disassembly (best guess): 0: db 86 fc 44 89 f9 fildl -0x676bb04(%rsi) 6: d3 e5 shl %cl,%ebp 8: 49 83 ee 80 sub $0xffffffffffffff80,%r14 c: 4c 89 f0 mov %r14,%rax f: 48 c1 e8 03 shr $0x3,%rax 13: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) 18: 74 08 je 0x22 1a: 4c 89 f7 mov %r14,%rdi 1d: e8 5c 65 f0 fc call 0xfcf0657e 22: 41 03 2e add (%r14),%ebp 25: 89 d8 mov %ebx,%eax 27: 89 ea mov %ebp,%edx 29: ee out %al,(%dx) * 2a: 5b pop %rbx <-- trapping instruction 2b: 41 5c pop %r12 2d: 41 5e pop %r14 2f: 41 5f pop %r15 31: 5d pop %rbp 32: e9 c7 3e ed 05 jmp 0x5ed3efe 37: cc int3 38: 44 89 f9 mov %r15d,%ecx 3b: 80 e1 07 and $0x7,%cl 3e: 38 c1 cmp %al,%cl