syzbot

INFO: task syz.0.229:6606 blocked for more than 143 seconds.
      Not tainted 6.16.0-rc5-syzkaller-00053-g8c2e52ebbe88 #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.229       state:D stack:24552 pid:6606  tgid:6606  ppid:5850   task_flags:0x40044c flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5401 [inline]
 __schedule+0x16f5/0x4d00 kernel/sched/core.c:6790
 __schedule_loop kernel/sched/core.c:6868 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6883
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6940
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:747
 rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
 netdev_run_todo+0x327/0xea0 net/core/dev.c:11376
 tun_detach drivers/net/tun.c:639 [inline]
 tun_chr_close+0x13c/0x1c0 drivers/net/tun.c:3396
 __fput+0x44c/0xa70 fs/file_table.c:465
 task_work_run+0x1d4/0x260 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x6b5/0x22e0 kernel/exit.c:964
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1105
 get_signal+0x1286/0x1340 kernel/signal.c:3034
 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
 do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7c2bd8e929
RSP: 002b:00007ffdf8025798 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f7c2bfb7ba0 RCX: 00007f7c2bd8e929
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f7c2bfb7ba0 R08: 000000000000c1fc R09: 00000003f8025a8f
R10: 00000000005f3380 R11: 0000000000000246 R12: 0000000000025470
R13: 00007ffdf8025890 R14: ffffffffffffffff R15: 00007ffdf80258b0
 </TASK>
INFO: task syz-executor:7203 blocked for more than 145 seconds.
      Not tainted 6.16.0-rc5-syzkaller-00053-g8c2e52ebbe88 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:22760 pid:7203  tgid:7203  ppid:1      task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5401 [inline]
 __schedule+0x16f5/0x4d00 kernel/sched/core.c:6790
 __schedule_loop kernel/sched/core.c:6868 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6883
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6940
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:747
 device_lock include/linux/device.h:884 [inline]
 device_del+0xa9/0x8e0 drivers/base/core.c:3843
 device_unregister+0x20/0xc0 drivers/base/core.c:3922
 nsim_bus_dev_del drivers/net/netdevsim/bus.c:462 [inline]
 del_device_store+0x2aa/0x360 drivers/net/netdevsim/bus.c:226
 kernfs_fop_write_iter+0x378/0x4f0 fs/kernfs/file.c:334
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x54b/0xa90 fs/read_write.c:686
 ksys_write+0x145/0x250 fs/read_write.c:738
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcc4798d3df
RSP: 002b:00007fffc03d9580 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fcc4798d3df
RDX: 0000000000000001 RSI: 00007fffc03d95d0 RDI: 0000000000000005
RBP: 00007fcc47a11d8d R08: 0000000000000000 R09: 00007fffc03d93d7
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001
R13: 00007fffc03d95d0 R14: 00007fcc486e4620 R15: 0000000000000003
 </TASK>
INFO: task syz-executor:7205 blocked for more than 146 seconds.
      Not tainted 6.16.0-rc5-syzkaller-00053-g8c2e52ebbe88 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:22616 pid:7205  tgid:7205  ppid:1      task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5401 [inline]
 __schedule+0x16f5/0x4d00 kernel/sched/core.c:6790
 __schedule_loop kernel/sched/core.c:6868 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6883
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6940
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:747
 del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
 kernfs_fop_write_iter+0x378/0x4f0 fs/kernfs/file.c:334
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x54b/0xa90 fs/read_write.c:686
 ksys_write+0x145/0x250 fs/read_write.c:738
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f258bd8d3df
RSP: 002b:00007ffec29bbdc0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007f258bd8d3df
RDX: 0000000000000001 RSI: 00007ffec29bbe10 RDI: 0000000000000005
RBP: 00007f258be11d8d R08: 0000000000000000 R09: 00007ffec29bbc17
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001
R13: 00007ffec29bbe10 R14: 00007f258cae4620 R15: 0000000000000003
 </TASK>
INFO: task syz.3.443:7242 blocked for more than 147 seconds.
      Not tainted 6.16.0-rc5-syzkaller-00053-g8c2e52ebbe88 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.443       state:D stack:23880 pid:7242  tgid:7241  ppid:5848   task_flags:0x400140 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5401 [inline]
 __schedule+0x16f5/0x4d00 kernel/sched/core.c:6790
 __schedule_loop kernel/sched/core.c:6868 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6883
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6940
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:747
 rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
 flush_rcu_work+0x84/0xb0 kernel/workqueue.c:4304
 kvfree_rcu_barrier+0x12b/0x160 mm/slab_common.c:2083
 kmem_cache_destroy+0x2e/0x160 mm/slab_common.c:492
 bio_put_slab block/bio.c:155 [inline]
 bioset_exit+0x583/0x690 block/bio.c:1758
 bch2_fs_fs_io_direct_exit+0x19/0x30 fs/bcachefs/fs-io-direct.c:685
 __bch2_fs_free fs/bcachefs/super.c:603 [inline]
 bch2_fs_release+0x22c/0x830 fs/bcachefs/super.c:667
 kobject_cleanup lib/kobject.c:689 [inline]
 kobject_release lib/kobject.c:720 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x22b/0x480 lib/kobject.c:737
 bch2_fs_get_tree+0xb6e/0x1520 fs/bcachefs/fs.c:2604
 vfs_get_tree+0x92/0x2b0 fs/super.c:1804
 do_new_mount+0x24a/0xa40 fs/namespace.c:3902
 do_mount fs/namespace.c:4239 [inline]
 __do_sys_mount fs/namespace.c:4450 [inline]
 __se_sys_mount+0x317/0x410 fs/namespace.c:4427
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5ad51900ca
RSP: 002b:00007f5ad603ae68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f5ad603aef0 RCX: 00007f5ad51900ca
RDX: 00002000000058c0 RSI: 0000200000005900 RDI: 00007f5ad603aeb0
RBP: 00002000000058c0 R08: 00007f5ad603aef0 R09: 0000000000010000
R10: 0000000000010000 R11: 0000000000000246 R12: 0000200000005900
R13: 00007f5ad603aeb0 R14: 00000000000058b4 R15: 0000200000000240
 </TASK>
INFO: task syz-executor:7342 blocked for more than 148 seconds.
      Not tainted 6.16.0-rc5-syzkaller-00053-g8c2e52ebbe88 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:22760 pid:7342  tgid:7342  ppid:1      task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5401 [inline]
 __schedule+0x16f5/0x4d00 kernel/sched/core.c:6790
 __schedule_loop kernel/sched/core.c:6868 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6883
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6940
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:747
 del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
 kernfs_fop_write_iter+0x378/0x4f0 fs/kernfs/file.c:334
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x54b/0xa90 fs/read_write.c:686
 ksys_write+0x145/0x250 fs/read_write.c:738
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa42a18d3df
RSP: 002b:00007ffec30cd3d0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fa42a18d3df
RDX: 0000000000000001 RSI: 00007ffec30cd420 RDI: 0000000000000005
RBP: 00007fa42a211d8d R08: 0000000000000000 R09: 00007ffec30cd227
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001
R13: 00007ffec30cd420 R14: 00007fa42aee4620 R15: 0000000000000003
 </TASK>

Showing all locks held in the system:
5 locks held by kworker/0:0/9:
1 lock held by khungtaskd/31:
 #0: ffffffff8e13f160 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8e13f160 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #0: ffffffff8e13f160 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
6 locks held by kworker/u8:6/1149:
 #0: ffff88801b2f6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
 #0: ffff88801b2f6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
 #1: ffffc900042cfbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #1: ffffc900042cfbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
 #2: ffffffff8f510c10 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800 net/core/net_namespace.c:662
 #3: ffff88807c23c0e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
 #3: ffff88807c23c0e8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline]
 #3: ffff88807c23c0e8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x10a/0x3d0 net/devlink/core.c:506
 #4: ffff88807c23f250 (&devlink->lock_key#3){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:276 [inline]
 #4: ffff88807c23f250 (&devlink->lock_key#3){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline]
 #4: ffff88807c23f250 (&devlink->lock_key#3){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x11c/0x3d0 net/devlink/core.c:506
 #5: ffffffff8e144b40 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
2 locks held by getty/5599:
 #0: ffff8880314160a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by syz-executor/5847:
 #0: ffffffff8e144b40 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
7 locks held by kworker/u9:5/5861:
 #0: ffff888029efb948 ((wq_completion)hci15){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
 #0: ffff888029efb948 ((wq_completion)hci15){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
 #1: ffffc90003d6fbc0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #1: ffffc90003d6fbc0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
 #2: ffff888052250dc0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d4/0x3a0 net/bluetooth/hci_sync.c:331
 #3: ffff8880522500b8 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0x1eb/0xdf0 net/bluetooth/hci_sync.c:5670
 #4: ffffffff8f685908 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2053 [inline]
 #4: ffffffff8f685908 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_failed+0x165/0x310 net/bluetooth/hci_conn.c:1275
 #5: ffff88807c4a6b38 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x70/0x680 net/bluetooth/l2cap_core.c:1762
 #6: ffffffff8e144c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
 #6: ffffffff8e144c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998
5 locks held by kworker/u9:6/5863:
 #0: ffff88802df2a948 ((wq_completion)hci14){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
 #0: ffff88802df2a948 ((wq_completion)hci14){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
 #1: ffffc90003cffbc0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #1: ffffc90003cffbc0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
 #2: ffff88802b460dc0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d4/0x3a0 net/bluetooth/hci_sync.c:331
 #3: ffff88802b4600b8 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0x1eb/0xdf0 net/bluetooth/hci_sync.c:5670
 #4: ffffffff8e144c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
 #4: ffffffff8e144c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:998
1 lock held by syz.0.229/6606:
 #0: ffffffff8e144b40 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
2 locks held by kworker/u8:11/6632:
1 lock held by syz.5.338/6886:
 #0: ffffffff8e144b40 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
1 lock held by syz.6.365/6963:
 #0: ffffffff8e144b40 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
1 lock held by syz.1.400/7081:
 #0: ffffffff8e144b40 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
1 lock held by syz.7.402/7085:
 #0: ffffffff8e144b40 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
5 locks held by syz-executor/7203:
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff888080e04488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff8881437e5008 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8edab048 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
 #4: ffff88807c23c0e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
 #4: ffff88807c23c0e8 (&dev->mutex){....}-{4:4}, at: device_del+0xa9/0x8e0 drivers/base/core.c:3843
4 locks held by syz-executor/7205:
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff888081a1c888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff8881437e5008 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8edab048 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
2 locks held by syz.3.443/7242:
 #0: ffffffff8e890988 (bio_slab_lock){+.+.}-{4:4}, at: bio_put_slab block/bio.c:140 [inline]
 #0: ffffffff8e890988 (bio_slab_lock){+.+.}-{4:4}, at: bioset_exit+0x44a/0x690 block/bio.c:1758
 #1: ffffffff8e144b40 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
4 locks held by syz-executor/7342:
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff888055eccc88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff8881437e5008 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8edab048 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
1 lock held by syz.8.492/7390:
 #0: ffffffff8e144b40 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
1 lock held by syz.9.516/7443:
 #0: ffffffff8e144b40 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786
4 locks held by syz-executor/7450:
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff888042a8b888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff8881437e5008 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8edab048 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
4 locks held by syz-executor/7463:
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff888045168088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff8881437e5008 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8edab048 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
4 locks held by syz-executor/7472:
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff8880894b3488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff8881437e5008 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8edab048 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
4 locks held by syz-executor/7484:
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff88804516bc88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff8881437e5008 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8edab048 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
4 locks held by syz-executor/7490:
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff88808c90e888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff8881437e5008 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8edab048 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
4 locks held by syz-executor/7504:
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff88809704c088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff8881437e5008 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8edab048 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
4 locks held by syz-executor/7522:
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff888050d95c88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff8881437e5008 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8edab048 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
4 locks held by syz-executor/7534:
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff888083e99488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff8881437e5008 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8edab048 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
4 locks held by syz-executor/7544:
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff88801cb6e088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff8881437e5008 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8edab048 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
4 locks held by syz-executor/7555:
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff88805326cc88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff8881437e5008 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8edab048 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
4 locks held by syz-executor/7560:
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff88805694dc88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff8881437e5008 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8edab048 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
4 locks held by syz-executor/7578:
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff8880573b5088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff8881437e5008 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8edab048 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
4 locks held by syz-executor/7597:
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff888095fa8088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff8881437e5008 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8edab048 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
4 locks held by syz-executor/7605:
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff888069c51c88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff8881437e5008 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8edab048 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216
4 locks held by syz-executor/7618:
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
 #0: ffff888035cf2428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:682
 #1: ffff888057223088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
 #2: ffff8881437e5008 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
 #3: ffffffff8edab048 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:216

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc5-syzkaller-00053-g8c2e52ebbe88 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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:158 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
 watchdog+0xfee/0x1030 kernel/hung_task.c:470
 kthread+0x711/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 9 Comm: kworker/0:0 Not tainted 6.16.0-rc5-syzkaller-00053-g8c2e52ebbe88 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_power_efficient neigh_periodic_work
RIP: 0010:__lock_acquire+0x6e/0xd20 kernel/locking/lockdep.c:5106
Code: 0c 85 c9 44 0f 44 c1 31 c9 48 3d f0 02 64 93 41 0f 45 c8 89 4c 24 0c 8b 0d 6f 60 0d 18 85 c9 0f 95 c0 83 fe 08 0f 92 c2 08 c2 <0f> 84 55 01 00 00 44 89 cd 83 fe 01 48 89 3c 24 77 0c 89 f0 48 8b
RSP: 0018:ffffc900000065e8 EFLAGS: 00000002
RAX: ffffffff99afba00 RBX: ffffffff8e13f160 RCX: 0000000000000000
RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff88801caf0000
RBP: ffffffff81729ae5 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff81acf3a0 R12: 0000000000000002
R13: ffffffff8e13f160 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888125c1b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31517ff8 CR3: 000000000df38000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:841 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
 unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:47
 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:548
 __call_rcu_common kernel/rcu/tree.c:3094 [inline]
 call_rcu+0x157/0x9c0 kernel/rcu/tree.c:3214
 slab_free_hook mm/slub.c:2345 [inline]
 slab_free mm/slub.c:4643 [inline]
 kmem_cache_free+0x309/0x400 mm/slub.c:4745