INFO: task syz.2.558:7464 blocked for more than 143 seconds. Not tainted 6.11.0-rc3-next-20240812-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.558 state:D stack:27392 pid:7464 tgid:7461 ppid:5225 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5270 [inline] __schedule+0x17ff/0x4ad0 kernel/sched/core.c:6639 __schedule_loop kernel/sched/core.c:6716 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6731 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6788 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a4/0xd70 kernel/locking/mutex.c:752 __fdget_pos+0x24e/0x310 fs/file.c:1187 fdget_pos include/linux/file.h:77 [inline] ksys_read+0x82/0x2c0 fs/read_write.c:610 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f29127779f9 RSP: 002b:00007f29121de038 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f2912906058 RCX: 00007f29127779f9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 00007f29127e58ee R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f2912906058 R15: 00007ffda6fe0208 Showing all locks held in the system: 3 locks held by kworker/u8:0/11: 5 locks held by kworker/u8:2/29: #0: ffff8880166e5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff8880166e5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90000a57d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90000a57d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fc7e3d0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:580 #3: ffffffff8fc8ae88 (rtnl_mutex){+.+.}-{3:3}, at: cleanup_net+0x6af/0xcc0 net/core/net_namespace.c:616 #4: ffffffff8e93cc78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:296 [inline] #4: ffffffff8e93cc78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:969 1 lock held by khungtaskd/31: #0: ffffffff8e9376e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e9376e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e9376e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6645 3 locks held by kworker/u8:7/4218: #0: ffff888015889148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff888015889148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc9000c647d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc9000c647d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fc8ae88 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 2 locks held by getty/4979: #0: ffff88802f8d90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6ac/0x1e00 drivers/tty/n_tty.c:2211 3 locks held by kworker/0:7/5307: #0: ffff888015880948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff888015880948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc9000463fd00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc9000463fd00 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fc8ae88 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 3 locks held by kworker/u8:13/6267: 2 locks held by syz.2.558/7462: 1 lock held by syz.2.558/7464: #0: ffff88802a00d9c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x24e/0x310 fs/file.c:1187 3 locks held by syz.0.600/7621: 1 lock held by syz.0.600/7624: #0: ffff888025f225c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x24e/0x310 fs/file.c:1187 3 locks held by kworker/1:0/8263: #0: ffff888015880948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff888015880948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc9000330fd00 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc9000330fd00 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8e93cc78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:328 [inline] #2: ffffffff8e93cc78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:969 1 lock held by syz-executor/8552: #0: ffffffff8fc8ae88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fc8ae88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 1 lock held by syz-executor/8560: #0: ffffffff8fc8ae88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fc8ae88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 3 locks held by syz.0.870/8638: #0: ffff88806a584d80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] #0: ffff88806a584d80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2692 #1: ffff88806a584078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x572/0x11a0 net/bluetooth/hci_sync.c:5145 #2: ffffffff8fdf6d28 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1977 [inline] #2: ffffffff8fdf6d28 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa6/0x240 net/bluetooth/hci_conn.c:2592 1 lock held by syz.4.896/8733: #0: ffffffff8fc8ae88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fc8ae88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 1 lock held by syz-executor/8736: #0: ffffffff8fc8ae88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fc8ae88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.11.0-rc3-next-20240812-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xff4/0x1040 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:144 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 29 Comm: kworker/u8:2 Not tainted 6.11.0-rc3-next-20240812-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Workqueue: netns cleanup_net RIP: 0010:unwind_next_frame+0x315/0x22d0 arch/x86/kernel/unwind_orc.c:505 Code: 64 48 01 d2 48 01 f2 0f 84 42 01 00 00 48 8d 5a 04 4c 8d 72 05 48 89 d8 48 c1 e8 03 48 bd 00 00 00 00 00 fc ff df 0f b6 04 28 <84> c0 0f 85 58 18 00 00 4c 89 f0 48 c1 e8 03 0f b6 04 28 84 c0 0f RSP: 0018:ffffc90000a56d30 EFLAGS: 00000a06 RAX: 0000000000000000 RBX: ffffffff909f0138 RCX: ffffffff9029c354 RDX: ffffffff909f0134 RSI: ffffffff909f0134 RDI: ffffffff814126e0 RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffc90000a56ef0 R10: ffffc90000a56e50 R11: ffffffff817f1fb0 R12: 0000000000000000 R13: ffffc90000a56e00 R14: ffffffff909f0139 R15: ffffffff815e6b3b FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff54a835000 CR3: 00000000763e2000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4032 [inline] slab_alloc_node mm/slub.c:4081 [inline] kmem_cache_alloc_node_noprof+0x16b/0x320 mm/slub.c:4124 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:667 alloc_skb include/linux/skbuff.h:1320 [inline] nlmsg_new include/net/netlink.h:1015 [inline] inet6_ifa_notify net/ipv6/addrconf.c:5610 [inline] __ipv6_ifa_notify+0x2e9/0x1230 net/ipv6/addrconf.c:6259 addrconf_ifdown+0xef0/0x1bd0 net/ipv6/addrconf.c:3984 addrconf_notify+0x3cb/0x1020 notifier_call_chain+0x19f/0x3e0 kernel/notifier.c:93 call_netdevice_notifiers_extack net/core/dev.c:2032 [inline] call_netdevice_notifiers net/core/dev.c:2046 [inline] dev_close_many+0x33c/0x4c0 net/core/dev.c:1587 unregister_netdevice_many_notify+0x50b/0x1c40 net/core/dev.c:11327 cleanup_net+0x75d/0xcc0 net/core/net_namespace.c:621 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd10 kernel/workqueue.c:3389 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:144 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244