Re: [syzbot] [block?] [trace?] INFO: task hung in blk_trace_remove (2)

From: syzbot
Date: Tue Jan 30 2024 - 11:03:23 EST


Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
INFO: task hung in blk_trace_setup

INFO: task syz-executor.4:5650 blocked for more than 143 seconds.
Not tainted 6.8.0-rc2-syzkaller-g861c0981648f-dirty #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.4 state:D stack:27776 pid:5650 tgid:5649 ppid:5434 flags:0x00000006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5400 [inline]
__schedule+0xf12/0x5c00 kernel/sched/core.c:6727
__schedule_loop kernel/sched/core.c:6802 [inline]
schedule+0xe9/0x270 kernel/sched/core.c:6817
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6874
__mutex_lock_common kernel/locking/mutex.c:684 [inline]
__mutex_lock+0x5b9/0x9d0 kernel/locking/mutex.c:752
blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:647
sg_ioctl_common drivers/scsi/sg.c:1118 [inline]
sg_ioctl+0x669/0x2760 drivers/scsi/sg.c:1160
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl fs/ioctl.c:857 [inline]
__x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f406fc7cda9
RSP: 002b:00007f4070a040c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f406fdabf80 RCX: 00007f406fc7cda9
RDX: 0000000020000040 RSI: 00000000c0481273 RDI: 0000000000000003
RBP: 00007f406fcc947a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f406fdabf80 R15: 00007ffc9ad00358
</TASK>
INFO: task syz-executor.4:5651 blocked for more than 143 seconds.
Not tainted 6.8.0-rc2-syzkaller-g861c0981648f-dirty #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.4 state:D stack:28480 pid:5651 tgid:5649 ppid:5434 flags:0x00000006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5400 [inline]
__schedule+0xf12/0x5c00 kernel/sched/core.c:6727
__schedule_loop kernel/sched/core.c:6802 [inline]
schedule+0xe9/0x270 kernel/sched/core.c:6817
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6874
__mutex_lock_common kernel/locking/mutex.c:684 [inline]
__mutex_lock+0x5b9/0x9d0 kernel/locking/mutex.c:752
blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:405
sg_ioctl_common drivers/scsi/sg.c:1126 [inline]
sg_ioctl+0x9ac/0x2760 drivers/scsi/sg.c:1160
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl fs/ioctl.c:857 [inline]
__x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f406fc7cda9
RSP: 002b:00007f40709e30c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f406fdac050 RCX: 00007f406fc7cda9
RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000003
RBP: 00007f406fcc947a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f406fdac050 R15: 00007ffc9ad00358
</TASK>
INFO: task syz-executor.1:5653 blocked for more than 144 seconds.
Not tainted 6.8.0-rc2-syzkaller-g861c0981648f-dirty #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.1 state:D stack:27776 pid:5653 tgid:5652 ppid:5428 flags:0x00000006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5400 [inline]
__schedule+0xf12/0x5c00 kernel/sched/core.c:6727
__schedule_loop kernel/sched/core.c:6802 [inline]
schedule+0xe9/0x270 kernel/sched/core.c:6817
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6874
__mutex_lock_common kernel/locking/mutex.c:684 [inline]
__mutex_lock+0x5b9/0x9d0 kernel/locking/mutex.c:752
blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:647
sg_ioctl_common drivers/scsi/sg.c:1118 [inline]
sg_ioctl+0x669/0x2760 drivers/scsi/sg.c:1160
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl fs/ioctl.c:857 [inline]
__x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f76ba07cda9
RSP: 002b:00007f76baed70c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f76ba1abf80 RCX: 00007f76ba07cda9
RDX: 0000000020000040 RSI: 00000000c0481273 RDI: 0000000000000003
RBP: 00007f76ba0c947a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f76ba1abf80 R15: 00007fffb67c90d8
</TASK>
INFO: task syz-executor.1:5655 blocked for more than 144 seconds.
Not tainted 6.8.0-rc2-syzkaller-g861c0981648f-dirty #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.1 state:D stack:29536 pid:5655 tgid:5652 ppid:5428 flags:0x00000006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5400 [inline]
__schedule+0xf12/0x5c00 kernel/sched/core.c:6727
__schedule_loop kernel/sched/core.c:6802 [inline]
schedule+0xe9/0x270 kernel/sched/core.c:6817
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6874
__mutex_lock_common kernel/locking/mutex.c:684 [inline]
__mutex_lock+0x5b9/0x9d0 kernel/locking/mutex.c:752
blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:405
sg_ioctl_common drivers/scsi/sg.c:1126 [inline]
sg_ioctl+0x9ac/0x2760 drivers/scsi/sg.c:1160
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl fs/ioctl.c:857 [inline]
__x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f76ba07cda9
RSP: 002b:00007f76baeb60c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f76ba1ac050 RCX: 00007f76ba07cda9
RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000003
RBP: 00007f76ba0c947a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f76ba1ac050 R15: 00007fffb67c90d8
</TASK>
INFO: task syz-executor.2:5662 blocked for more than 145 seconds.
Not tainted 6.8.0-rc2-syzkaller-g861c0981648f-dirty #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2 state:D stack:27776 pid:5662 tgid:5660 ppid:5443 flags:0x00000006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5400 [inline]
__schedule+0xf12/0x5c00 kernel/sched/core.c:6727
__schedule_loop kernel/sched/core.c:6802 [inline]
schedule+0xe9/0x270 kernel/sched/core.c:6817
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6874
__mutex_lock_common kernel/locking/mutex.c:684 [inline]
__mutex_lock+0x5b9/0x9d0 kernel/locking/mutex.c:752
blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:647
sg_ioctl_common drivers/scsi/sg.c:1118 [inline]
sg_ioctl+0x669/0x2760 drivers/scsi/sg.c:1160
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl fs/ioctl.c:857 [inline]
__x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7efebe87cda9
RSP: 002b:00007efebf5ca0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007efebe9abf80 RCX: 00007efebe87cda9
RDX: 0000000020000040 RSI: 00000000c0481273 RDI: 0000000000000003
RBP: 00007efebe8c947a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007efebe9abf80 R15: 00007ffd09f13438
</TASK>
INFO: task syz-executor.2:5663 blocked for more than 145 seconds.
Not tainted 6.8.0-rc2-syzkaller-g861c0981648f-dirty #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2 state:D stack:29536 pid:5663 tgid:5660 ppid:5443 flags:0x00000006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5400 [inline]
__schedule+0xf12/0x5c00 kernel/sched/core.c:6727
__schedule_loop kernel/sched/core.c:6802 [inline]
schedule+0xe9/0x270 kernel/sched/core.c:6817
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6874
__mutex_lock_common kernel/locking/mutex.c:684 [inline]
__mutex_lock+0x5b9/0x9d0 kernel/locking/mutex.c:752
blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:405
sg_ioctl_common drivers/scsi/sg.c:1126 [inline]
sg_ioctl+0x9ac/0x2760 drivers/scsi/sg.c:1160
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl fs/ioctl.c:857 [inline]
__x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7efebe87cda9
RSP: 002b:00007efebf5a90c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007efebe9ac050 RCX: 00007efebe87cda9
RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000003
RBP: 00007efebe8c947a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007efebe9ac050 R15: 00007ffd09f13438
</TASK>
INFO: task syz-executor.0:5665 blocked for more than 145 seconds.
Not tainted 6.8.0-rc2-syzkaller-g861c0981648f-dirty #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0 state:D stack:27776 pid:5665 tgid:5664 ppid:5435 flags:0x00000006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5400 [inline]
__schedule+0xf12/0x5c00 kernel/sched/core.c:6727
__schedule_loop kernel/sched/core.c:6802 [inline]
schedule+0xe9/0x270 kernel/sched/core.c:6817
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6874
__mutex_lock_common kernel/locking/mutex.c:684 [inline]
__mutex_lock+0x5b9/0x9d0 kernel/locking/mutex.c:752
blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:647
sg_ioctl_common drivers/scsi/sg.c:1118 [inline]
sg_ioctl+0x669/0x2760 drivers/scsi/sg.c:1160
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl fs/ioctl.c:857 [inline]
__x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f640727cda9
RSP: 002b:00007f640802c0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f64073abf80 RCX: 00007f640727cda9
RDX: 0000000020000040 RSI: 00000000c0481273 RDI: 0000000000000003
RBP: 00007f64072c947a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f64073abf80 R15: 00007fff0e30aa68
</TASK>
INFO: task syz-executor.0:5667 blocked for more than 146 seconds.
Not tainted 6.8.0-rc2-syzkaller-g861c0981648f-dirty #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0 state:D stack:29536 pid:5667 tgid:5664 ppid:5435 flags:0x00000006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5400 [inline]
__schedule+0xf12/0x5c00 kernel/sched/core.c:6727
__schedule_loop kernel/sched/core.c:6802 [inline]
schedule+0xe9/0x270 kernel/sched/core.c:6817
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6874
__mutex_lock_common kernel/locking/mutex.c:684 [inline]
__mutex_lock+0x5b9/0x9d0 kernel/locking/mutex.c:752
blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:405
sg_ioctl_common drivers/scsi/sg.c:1126 [inline]
sg_ioctl+0x9ac/0x2760 drivers/scsi/sg.c:1160
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl fs/ioctl.c:857 [inline]
__x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f640727cda9
RSP: 002b:00007f640800b0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f64073ac050 RCX: 00007f640727cda9
RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000003
RBP: 00007f64072c947a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f64073ac050 R15: 00007fff0e30aa68
</TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/29:
#0: ffffffff8d1acbe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
#0: ffffffff8d1acbe0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline]
#0: ffffffff8d1acbe0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6614
2 locks held by kworker/u4:2/38:
3 locks held by kworker/0:2/922:
#0: ffff888029122d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x789/0x15d0 kernel/workqueue.c:2608
#1: ffffc90004167d80 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7eb/0x15d0 kernel/workqueue.c:2609
#2: ffffffff8ecc25a8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcf/0x14b0 net/ipv6/addrconf.c:4129
5 locks held by kworker/u5:1/4459:
#0: ffff88802168a538 ((wq_completion)hci8){+.+.}-{0:0}, at: process_one_work+0x789/0x15d0 kernel/workqueue.c:2608
#1: ffffc9000d8f7d80 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x7eb/0x15d0 kernel/workqueue.c:2609
#2: ffff8882053c5060 (&hdev->req_lock){+.+.}-{3:3}, at: hci_cmd_sync_work+0x170/0x410 net/bluetooth/hci_sync.c:305
#3: ffff8882053c4078 (&hdev->lock){+.+.}-{3:3}, at: hci_abort_conn_sync+0x150/0xb50 net/bluetooth/hci_sync.c:5337
#4: ffffffff8d1b8438 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline]
#4: ffffffff8d1b8438 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3ff/0x800 kernel/rcu/tree_exp.h:995
2 locks held by getty/4816:
#0: ffff888029b910a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc6/0x1490 drivers/tty/n_tty.c:2201
2 locks held by kworker/0:5/5076:
#0: ffff88801308a938 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x789/0x15d0 kernel/workqueue.c:2608
#1: ffffc900042e7d80 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7eb/0x15d0 kernel/workqueue.c:2609
3 locks held by kworker/1:7/5518:
#0: ffff888029122d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x789/0x15d0 kernel/workqueue.c:2608
#1: ffffc900097a7d80 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7eb/0x15d0 kernel/workqueue.c:2609
#2: ffffffff8ecc25a8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcf/0x14b0 net/ipv6/addrconf.c:4129
3 locks held by syz-executor.5/5642:
1 lock held by syz-executor.4/5650:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:647
1 lock held by syz-executor.4/5651:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:405
1 lock held by syz-executor.1/5653:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:647
1 lock held by syz-executor.1/5655:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:405
1 lock held by syz-executor.2/5662:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:647
1 lock held by syz-executor.2/5663:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:405
1 lock held by syz-executor.0/5665:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:647
1 lock held by syz-executor.0/5667:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:405
1 lock held by syz-executor.3/5951:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:647
1 lock held by syz-executor.3/5952:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:405
1 lock held by syz-executor.5/5979:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:647
1 lock held by syz-executor.5/5980:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:405
1 lock held by syz-executor.1/5983:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:647
1 lock held by syz-executor.1/5986:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:405
1 lock held by syz-executor.4/5993:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:647
1 lock held by syz-executor.4/5994:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:405
1 lock held by syz-executor.0/5997:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:647
1 lock held by syz-executor.0/5998:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:405
1 lock held by syz-executor.2/6000:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:647
1 lock held by syz-executor.2/6001:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:405
1 lock held by syz-executor.3/6019:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:647
1 lock held by syz-executor.3/6020:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:405
1 lock held by syz-executor.5/6093:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:647
1 lock held by syz-executor.5/6094:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:405
1 lock held by syz-executor.1/6105:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:647
1 lock held by syz-executor.1/6106:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:405
1 lock held by syz-executor.4/6109:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:647
1 lock held by syz-executor.4/6110:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:405
1 lock held by syz-executor.2/6120:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:647
1 lock held by syz-executor.2/6121:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:405
1 lock held by syz-executor.0/6127:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:647
1 lock held by syz-executor.0/6128:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:405
1 lock held by syz-executor.3/6138:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:647
1 lock held by syz-executor.3/6139:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:405
1 lock held by syz-executor.1/6165:
#0: ffffffff8ecc25a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#0: ffffffff8ecc25a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x372/0xe00 net/core/rtnetlink.c:6612
1 lock held by syz-executor.4/6168:
#0: ffffffff8ecc25a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#0: ffffffff8ecc25a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x372/0xe00 net/core/rtnetlink.c:6612
1 lock held by syz-executor.2/6184:
#0: ffffffff8ecc25a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#0: ffffffff8ecc25a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x372/0xe00 net/core/rtnetlink.c:6612
2 locks held by syz-executor.0/6187:
#0: ffffffff8ecc25a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#0: ffffffff8ecc25a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x372/0xe00 net/core/rtnetlink.c:6612
#1: ffffffff8d1b8438 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline]
#1: ffffffff8d1b8438 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3ff/0x800 kernel/rcu/tree_exp.h:995
1 lock held by syz-executor.5/6191:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:647
1 lock held by syz-executor.5/6192:
#0: ffff88801f9a1070 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:405
1 lock held by syz-executor.3/6199:
#0: ffffffff8ecc25a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#0: ffffffff8ecc25a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x372/0xe00 net/core/rtnetlink.c:6612

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

NMI backtrace for cpu 1
CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.8.0-rc2-syzkaller-g861c0981648f-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
nmi_cpu_backtrace+0x277/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x299/0x300 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+0xf87/0x1210 kernel/hung_task.c:379
kthread+0x2c6/0x3a0 kernel/kthread.c:388
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
</TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 59 Comm: kworker/u4:4 Not tainted 6.8.0-rc2-syzkaller-g861c0981648f-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Workqueue: bat_events batadv_nc_worker
RIP: 0010:check_preemption_disabled+0x2/0xe0 lib/smp_processor_id.c:13
Code: ac 04 85 c0 74 1a 65 8b 05 b3 22 74 75 85 c0 75 0f 65 8b 05 bc 1f 74 75 85 c0 74 04 90 0f 0b 90 e9 83 fc ff ff 0f 1f 00 41 54 <55> 53 48 83 ec 08 65 8b 1d cd 59 75 75 65 8b 05 c2 59 75 75 a9 ff
RSP: 0018:ffffc900015a7a48 EFLAGS: 00000082
RAX: 0000000000000001 RBX: 1ffff920002b4f4d RCX: 00000000154dd6e4
RDX: 0000000000000001 RSI: ffffffff8accb300 RDI: ffffffff8b2fdc00
RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff242afe8
R10: ffffffff92157f47 R11: 0000000000000002 R12: 0000000000000000
R13: 0000000000000000 R14: ffffffff8d1acbe0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055ae8684eb68 CR3: 000000006b120000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<NMI>
</NMI>
<TASK>
lockdep_recursion_finish kernel/locking/lockdep.c:467 [inline]
lock_acquire kernel/locking/lockdep.c:5756 [inline]
lock_acquire+0x1be/0x520 kernel/locking/lockdep.c:5719
rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
rcu_read_lock include/linux/rcupdate.h:750 [inline]
batadv_nc_process_nc_paths.part.0+0xe4/0x3e0 net/batman-adv/network-coding.c:687
batadv_nc_process_nc_paths net/batman-adv/network-coding.c:679 [inline]
batadv_nc_worker+0xded/0x10e0 net/batman-adv/network-coding.c:735
process_one_work+0x886/0x15d0 kernel/workqueue.c:2633
process_scheduled_works kernel/workqueue.c:2706 [inline]
worker_thread+0x8b9/0x1290 kernel/workqueue.c:2787
kthread+0x2c6/0x3a0 kernel/kthread.c:388
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
</TASK>


Tested on:

commit: 861c0981 Merge tag 'jfs-6.8-rc3' of github.com:kleikam..
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=175259dfe80000
kernel config: https://syzkaller.appspot.com/x/.config?x=b168fa511db3ca08
dashboard link: https://syzkaller.appspot.com/bug?extid=2373f6be3e6de4f92562
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
patch: https://syzkaller.appspot.com/x/patch.diff?x=17cf4860180000