syzbot

INFO: task jfsCommit:122 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.[  347.216661][   T38] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:jfsCommit       state:D stack:26352 pid:122   tgid:122   ppid:2      task_flags:0x200040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1480/0x50a0 kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6960
 io_schedule+0x81/0xe0 kernel/sched/core.c:7789
 __lock_metapage fs/jfs/jfs_metapage.c:52 [inline]
 lock_metapage+0x1f3/0x400 fs/jfs/jfs_metapage.c:66
 __get_metapage+0x49a/0xde0 fs/jfs/jfs_metapage.c:748
 diIAGRead+0xce/0x140 fs/jfs/jfs_imap.c:2672
 diFree+0x97f/0x2c30 fs/jfs/jfs_imap.c:959
 jfs_evict_inode+0x331/0x440 fs/jfs/inode.c:162
 evict+0x5f4/0xae0 fs/inode.c:837
 txLazyCommit fs/jfs/jfs_txnmgr.c:2665 [inline]
 jfs_lazycommit+0x3f1/0xa10 fs/jfs/jfs_txnmgr.c:2734
 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
 </TASK>
INFO: task jfsCommit:123 blocked 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:26712 pid:123   tgid:123   ppid:2      task_flags:0x200040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1480/0x50a0 kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6960
 io_schedule+0x81/0xe0 kernel/sched/core.c:7789
 __lock_metapage fs/jfs/jfs_metapage.c:52 [inline]
 lock_metapage+0x1f3/0x400 fs/jfs/jfs_metapage.c:66
 __get_metapage+0x49a/0xde0 fs/jfs/jfs_metapage.c:748
 diIAGRead+0xce/0x140 fs/jfs/jfs_imap.c:2672
 diFree+0x97f/0x2c30 fs/jfs/jfs_imap.c:959
 jfs_evict_inode+0x331/0x440 fs/jfs/inode.c:162
 evict+0x5f4/0xae0 fs/inode.c:837
 txLazyCommit fs/jfs/jfs_txnmgr.c:2665 [inline]
 jfs_lazycommit+0x3f1/0xa10 fs/jfs/jfs_txnmgr.c:2734
 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
 </TASK>

Showing all locks held in the system:
10 locks held by ktimers/0/16:
1 lock held by khungtaskd/38:
 #0: ffffffff8d5ae880 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8d5ae880 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
 #0: ffffffff8d5ae880 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by jfsCommit/122:
 #0: ffff888024798900 (&(imap->im_aglock[index])){+.+.}-{4:4}, at: diFree+0x29b/0x2c30 fs/jfs/jfs_imap.c:889
 #1: ffff88805eed2868 (&jfs_ip->rdwrlock/1){.+.+}-{4:4}, at: diFree+0x2b9/0x2c30 fs/jfs/jfs_imap.c:894
2 locks held by jfsCommit/123:
 #0: ffff88803db68900 (&(imap->im_aglock[index])){+.+.}-{4:4}, at: diFree+0x29b/0x2c30 fs/jfs/jfs_imap.c:889
 #1: ffff88805eed7668 (&jfs_ip->rdwrlock/1){.+.+}-{4:4}, at: diFree+0x2b9/0x2c30 fs/jfs/jfs_imap.c:894
1 lock held by syslogd/5148:
 #0: ffff88814a066f18 (&ei->socket.wq.wait){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline]
 #0: ffff88814a066f18 (&ei->socket.wq.wait){+.+.}-{3:3}, at: finish_wait+0xbf/0x1f0 kernel/sched/wait.c:394
3 locks held by klogd/5155:
2 locks held by getty/5557:
 #0: ffff88814e83d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc90003e7e2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x44f/0x1460 drivers/tty/n_tty.c:2211
2 locks held by syz-executor/5930:
 #0: ffff88802f76e0d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline]
 #0: ffff88802f76e0d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
 #0: ffff88802f76e0d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
 #1: ffffffff8d9f2458 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443
2 locks held by syz-executor/5936:
 #0: ffff88803617a0d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline]
 #0: ffff88803617a0d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
 #0: ffff88803617a0d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
 #1: ffffffff8d9f2458 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443
2 locks held by syz-executor/5943:
 #0: ffff8880525c40d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline]
 #0: ffff8880525c40d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
 #0: ffff8880525c40d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
 #1: ffffffff8d9f2458 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443
2 locks held by syz-executor/5945:
 #0: ffff8880267580d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline]
 #0: ffff8880267580d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
 #0: ffff8880267580d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
 #1: ffffffff8d9f2458 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443
2 locks held by syz-executor/6190:
 #0: ffff888030f980d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline]
 #0: ffff888030f980d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
 #0: ffff888030f980d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
 #1: ffffffff8d9f2458 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443
2 locks held by syz-executor/6217:
 #0: ffff888031b820d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline]
 #0: ffff888031b820d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
 #0: ffff888031b820d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
 #1: ffffffff8d9f2458 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443
2 locks held by syz-executor/6236:
 #0: ffff88801f3660d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline]
 #0: ffff88801f3660d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
 #0: ffff88801f3660d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
 #1: ffffffff8d9f2458 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443
4 locks held by syz-executor/6237:
 #0: ffff88803864e480 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:499
 #1: ffff88805eed5d78 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1072 [inline]
 #1: ffff88805eed5d78 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2864 [inline]
 #1: ffff88805eed5d78 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2875 [inline]
 #1: ffff88805eed5d78 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: do_unlinkat+0x1b2/0x570 fs/namei.c:5420
 #2: ffff88805eed7ab8 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline]
 #2: ffff88805eed7ab8 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: vfs_unlink+0xef/0x650 fs/namei.c:5355
 #3: ffff88805eed7668 (&jfs_ip->rdwrlock#2){+.+.}-{4:4}, at: jfs_unlink+0x1d8/0xa20 fs/jfs/namei.c:488
4 locks held by syz-executor/6268:
 #0: ffff88805e062480 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:499
 #1: ffff88805eed0f78 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1072 [inline]
 #1: ffff88805eed0f78 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2864 [inline]
 #1: ffff88805eed0f78 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2875 [inline]
 #1: ffff88805eed0f78 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: do_unlinkat+0x1b2/0x570 fs/namei.c:5420
 #2: ffff88805eed2cb8 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline]
 #2: ffff88805eed2cb8 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: vfs_unlink+0xef/0x650 fs/namei.c:5355
 #3: ffff88805eed2868 (&jfs_ip->rdwrlock#2){+.+.}-{4:4}, at: jfs_unlink+0x1d8/0xa20 fs/jfs/namei.c:488
1 lock held by syz-executor/6595:
 #0: ffff88805c9f40d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline]
 #0: ffff88805c9f40d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
 #0: ffff88805c9f40d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
1 lock held by syz.2.91/7195:
4 locks held by syz.0.90/7194:
1 lock held by syz.4.92/7198:
4 locks held by syz.5.93/7202:
5 locks held by syz.3.94/7210:
2 locks held by sed/7213:

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 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
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 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 10/25/2025
RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:400
Code: e8 4e 23 b6 fc 44 89 f9 d3 e3 49 83 ee 80 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 df 89 18 fd 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f c3 cc cc cc cc cc 44 89 f9 80 e1 07
RSP: 0018:ffffc90000167938 EFLAGS: 00000206
RAX: 1ffffffff31eef05 RBX: 00000000000003f9 RCX: 0000000000000000
RDX: 00000000000003f9 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000167ad0 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff850a4ee0 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffffffff98f77be0 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888126d12000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5f539dfe9c CR3: 00000000269ba000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 serial_port_in include/linux/serial_core.h:806 [inline]
 serial8250_console_write+0x372/0x1b40 drivers/tty/serial/8250/8250_port.c:3306
 console_emit_next_record kernel/printk/printk.c:3109 [inline]
 console_flush_one_record+0x6b5/0xbe0 kernel/printk/printk.c:3215
 legacy_kthread_func+0x16f/0x210 kernel/printk/printk.c:3674
 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
 </TASK>