syzbot

INFO: task syz-executor:4305 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:21504 pid: 4305 ppid:     1 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xc71/0x2390 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1452
 jfs_umount+0x28f/0x360 fs/jfs/jfs_umount.c:116
 jfs_put_super+0x88/0x190 fs/jfs/super.c:194
 generic_shutdown_super+0x130/0x300 fs/super.c:475
 kill_block_super+0x7c/0xe0 fs/super.c:1427
 deactivate_locked_super+0x93/0xf0 fs/super.c:335
 cleanup_mnt+0x418/0x4d0 fs/namespace.c:1148
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f1f877439f7
RSP: 002b:00007ffd1e0ced68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f1f877c4d7d RCX: 00007f1f877439f7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd1e0cee20
RBP: 00007ffd1e0cee20 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd1e0cfeb0
R13: 00007f1f877c4d7d R14: 0000000000013cee R15: 00007ffd1e0cfef0
 </TASK>
INFO: task syz-executor:4315 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:21824 pid: 4315 ppid:     1 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xc71/0x2390 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1452
 jfs_umount+0x28f/0x360 fs/jfs/jfs_umount.c:116
 jfs_put_super+0x88/0x190 fs/jfs/super.c:194
 generic_shutdown_super+0x130/0x300 fs/super.c:475
 kill_block_super+0x7c/0xe0 fs/super.c:1427
 deactivate_locked_super+0x93/0xf0 fs/super.c:335
 cleanup_mnt+0x418/0x4d0 fs/namespace.c:1148
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fef591f49f7
RSP: 002b:00007ffd098bfc78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fef59275d7d RCX: 00007fef591f49f7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd098bfd30
RBP: 00007ffd098bfd30 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd098c0dc0
R13: 00007fef59275d7d R14: 0000000000013c25 R15: 00007ffd098c0e00
 </TASK>

Showing all locks held in the system:
2 locks held by kworker/u4:0/9:
1 lock held by khungtaskd/27:
 #0: ffffffff8c11c760 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by kworker/u4:3/155:
2 locks held by getty/3947:
 #0: ffff88814cc87098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc90002d032e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
2 locks held by syz-executor/4305:
 #0: ffff88807b4c20e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
 #1: ffffffff8c4c3c28 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1452
2 locks held by syz-executor/4311:
 #0: ffff88802370c0e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
 #1: ffffffff8c4c3c28 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1452
2 locks held by syz-executor/4315:
 #0: ffff88807b9d40e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
 #1: ffffffff8c4c3c28 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1452
2 locks held by syz-executor/4422:
 #0: ffff8880591ce0e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
 #1: ffffffff8c4c3c28 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1452
2 locks held by syz-executor/4448:
 #0: ffff8880770f40e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
 #1: ffffffff8c4c3c28 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1452
2 locks held by syz-executor/4469:
 #0: ffff88807b9ca0e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
 #1: ffffffff8c4c3c28 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1452
2 locks held by syz-executor/4472:
 #0: ffff88805cade0e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
 #1: ffffffff8c4c3c28 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1452
2 locks held by syz-executor/4473:
 #0: ffff88807e7080e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
 #1: ffffffff8c4c3c28 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1452
2 locks held by syz-executor/4556:
 #0: ffff8880475bc0e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
 #1: ffffffff8c4c3c28 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1452
1 lock held by syz-executor/4594:
 #0: ffff888042d520e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
1 lock held by udevd/4724:
2 locks held by dhcpcd/5271:
 #0: ffff8880471b2120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1731 [inline]
 #0: ffff8880471b2120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x35/0xce0 net/packet/af_packet.c:3212
 #1: ffffffff8c1211e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
 #1: ffffffff8c1211e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x347/0x6b0 kernel/rcu/tree_exp.h:845
2 locks held by dhcpcd/5272:
 #0: ffff88805dd2c120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1731 [inline]
 #0: ffff88805dd2c120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x35/0xce0 net/packet/af_packet.c:3212
 #1: ffffffff8c1211e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
 #1: ffffffff8c1211e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x320/0x6b0 kernel/rcu/tree_exp.h:845
2 locks held by syz.5.597/5273:
1 lock held by dhcpcd/5274:
 #0: ffff888048494120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1731 [inline]
 #0: ffff888048494120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x35/0xce0 net/packet/af_packet.c:3212
2 locks held by syz.2.598/5275:
2 locks held by syz.4.599/5276:

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

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
 watchdog+0xe0f/0xe50 kernel/hung_task.c:369
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 5273 Comm: syz.5.597 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:match_held_lock+0x77/0xb0 kernel/locking/lockdep.c:5102
Code: 00 48 c7 c1 80 5f 94 8f 48 29 c8 48 c1 f8 06 48 be ab aa aa aa aa aa aa aa 48 0f af f0 b9 01 00 00 00 48 39 d6 74 02 31 c9 5b <89> c8 c3 e8 e1 4d 2e fa 85 c0 74 f1 83 3d 5e 5d c0 03 00 75 e8 48
RSP: 0018:ffffc9000e147970 EFLAGS: 00000046
RAX: 0000000000000002 RBX: ffff88802bbcbb80 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8c11c7c0 RDI: ffff88802bbcc698
RBP: 00000000ffffffff R08: dffffc0000000000 R09: fffff9400024e347
R10: fffff9400024e347 R11: 1ffffd400024e346 R12: 0000000000000001
R13: 0000000000000246 R14: ffffffff8c11c7c0 R15: ffff88802bbcc698
FS:  000055557ba8a500(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f320ccf4000 CR3: 000000005d9e1000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __lock_is_held kernel/locking/lockdep.c:5366 [inline]
 lock_is_held_type+0xa6/0x190 kernel/locking/lockdep.c:5666
 lock_is_held include/linux/lockdep.h:287 [inline]
 ___might_sleep+0xa3/0x600 kernel/sched/core.c:9624
 generic_perform_write+0x376/0x530 mm/filemap.c:3803
 __generic_file_write_iter+0x25f/0x4e0 mm/filemap.c:3912
 generic_file_write_iter+0xa6/0x1b0 mm/filemap.c:3944
 call_write_iter include/linux/fs.h:2173 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0x712/0xd00 fs/read_write.c:594
 ksys_write+0x14d/0x250 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f86d605e17f
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48
RSP: 002b:00007fff17312d60 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007f86d605e17f
RDX: 0000000001000000 RSI: 00007f86cd2cf000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000006256
R10: 000020000000bdc2 R11: 0000000000000293 R12: 0000000000000003
R13: 00007fff17312e60 R14: 00007fff17312e20 R15: 00007f86cd2cf000
 </TASK>