INFO: task kworker/u8:20:12680 blocked for more than 143 seconds. Not tainted 6.15.0-rc4-syzkaller-00746-g836b313a14a3 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:20 state:D stack:21400 pid:12680 tgid:12680 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:746 rdma_dev_change_netns+0x39/0x300 drivers/infiniband/core/device.c:1664 rdma_dev_exit_net+0x203/0x340 drivers/infiniband/core/device.c:1144 ops_exit_list net/core/net_namespace.c:200 [inline] ops_undo_list+0x497/0x990 net/core/net_namespace.c:253 cleanup_net+0x4c5/0x8a0 net/core/net_namespace.c:686 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task syz.4.2812:16129 blocked for more than 144 seconds. Not tainted 6.15.0-rc4-syzkaller-00746-g836b313a14a3 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.2812 state:D stack:23784 pid:16129 tgid:16128 ppid:5839 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:148 disable_device+0x1c6/0x320 drivers/infiniband/core/device.c:1288 __ib_unregister_device+0x2cb/0x3f0 drivers/infiniband/core/device.c:1516 ib_unregister_device_and_put+0xb8/0xf0 drivers/infiniband/core/device.c:1581 nldev_dellink+0x2d1/0x320 drivers/infiniband/core/nldev.c:1826 rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:-1 [inline] rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline] rdma_nl_rcv+0x6bf/0x9a0 drivers/infiniband/core/netlink.c:259 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x758/0x8d0 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:727 ____sys_sendmsg+0x505/0x830 net/socket.c:2566 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2620 __sys_sendmsg net/socket.c:2652 [inline] __do_sys_sendmsg net/socket.c:2657 [inline] __se_sys_sendmsg net/socket.c:2655 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2655 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f583458e969 RSP: 002b:00007f58354e1038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f58347b5fa0 RCX: 00007f583458e969 RDX: 0000000000000000 RSI: 00002000000002c0 RDI: 0000000000000006 RBP: 00007f5834610ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f58347b5fa0 R15: 00007fffd6894028 Showing all locks held in the system: 2 locks held by ksoftirqd/0/15: 1 lock held by khungtaskd/31: #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764 2 locks held by getty/5582: #0: ffff8880303150a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fee2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 3 locks held by kworker/u8:11/12666: #0: ffff88801a089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801a089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc90002ec7c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90002ec7c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffffffff8f2f4748 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 4 locks held by kworker/u8:12/12667: 3 locks held by kworker/u8:18/12675: #0: ffff88802f958148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88802f958148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc90002e97c60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90002e97c60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffffffff8f2f4748 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8f2f4748 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x112/0x14b0 net/ipv6/addrconf.c:4195 4 locks held by kworker/u8:20/12680: #0: ffff88801aef6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801aef6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc9000221fc60 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000221fc60 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffffffff8f2e7c10 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x8a0 net/core/net_namespace.c:662 #3: ffff88807c0a46d0 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300 drivers/infiniband/core/device.c:1664 2 locks held by syz.4.2812/16129: #0: ffffffff99bcefd8 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:164 [inline] #0: ffffffff99bcefd8 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline] #0: ffffffff99bcefd8 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv+0x316/0x9a0 drivers/infiniband/core/netlink.c:259 #1: ffff88807c0a46d0 (&device->unregistration_lock){+.+.}-{4:4}, at: __ib_unregister_device+0x284/0x3f0 drivers/infiniband/core/device.c:1512 2 locks held by syz.2.3047/16887: #0: ffffffff8f2e7c10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x317/0x590 net/core/net_namespace.c:570 #1: ffff88807c0a46d0 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300 drivers/infiniband/core/device.c:1664 2 locks held by syz.0.3348/18002: #0: ffffffff8f2e7c10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x317/0x590 net/core/net_namespace.c:570 #1: ffff88807c0a46d0 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300 drivers/infiniband/core/device.c:1664 2 locks held by syz.5.3572/18646: #0: ffffffff8f2e7c10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x317/0x590 net/core/net_namespace.c:570 #1: ffff88807c0a46d0 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300 drivers/infiniband/core/device.c:1664 2 locks held by syz.7.3679/19112: #0: ffffffff8f2e7c10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x317/0x590 net/core/net_namespace.c:570 #1: ffff88807c0a46d0 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300 drivers/infiniband/core/device.c:1664 2 locks held by syz.8.3735/19330: #0: ffffffff8f2e7c10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x317/0x590 net/core/net_namespace.c:570 #1: ffff88807c0a46d0 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300 drivers/infiniband/core/device.c:1664 2 locks held by syz.4.3738/19384: #0: ffffffff8f2e7c10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x317/0x590 net/core/net_namespace.c:570 #1: ffff88807c0a46d0 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300 drivers/infiniband/core/device.c:1664 2 locks held by syz.9.3753/19462: #0: ffffffff8f2e7c10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x317/0x590 net/core/net_namespace.c:570 #1: ffff88807c0a46d0 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300 drivers/infiniband/core/device.c:1664 2 locks held by syz-executor/19477: #0: ffff888036f34d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] #0: ffff888036f34d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x1fe/0x500 net/bluetooth/hci_core.c:2678 #1: ffff888036f34078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x66a/0x1330 net/bluetooth/hci_sync.c:5213 4 locks held by syz-executor/19512: #0: ffff88803ac80d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] #0: ffff88803ac80d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x1fe/0x500 net/bluetooth/hci_core.c:2678 #1: ffff88803ac80078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x66a/0x1330 net/bluetooth/hci_sync.c:5213 #2: ffffffff8f45b688 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2064 [inline] #2: ffffffff8f45b688 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x230 net/bluetooth/hci_conn.c:2534 #3: ffff888035c55b38 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x70/0x680 net/bluetooth/l2cap_core.c:1761 3 locks held by syz-executor/19544: #0: ffff8880492f4d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] #0: ffff8880492f4d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x1fe/0x500 net/bluetooth/hci_core.c:2678 #1: ffff8880492f4078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x66a/0x1330 net/bluetooth/hci_sync.c:5213 #2: ffffffff8f45b688 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2064 [inline] #2: ffffffff8f45b688 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x230 net/bluetooth/hci_conn.c:2534 1 lock held by syz-executor/19557: #0: ffffffff8f2f4748 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f2f4748 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_newaddr+0x5b7/0xd20 net/ipv6/addrconf.c:5028 3 locks held by syz-executor/19572: #0: ffffffff8ea8e3e0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8ea8e3e0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8ea8e3e0 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8f2f4748 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f2f4748 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8f2f4748 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4065 #2: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #2: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc4-syzkaller-00746-g836b313a14a3 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025 Call Trace: 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:274 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:437 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 19572 Comm: syz-executor Not tainted 6.15.0-rc4-syzkaller-00746-g836b313a14a3 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025 RIP: 0010:page_pool_page_is_pp include/linux/mm.h:4317 [inline] RIP: 0010:page_expected_state mm/page_alloc.c:895 [inline] RIP: 0010:free_page_is_bad mm/page_alloc.c:940 [inline] RIP: 0010:free_pages_prepare mm/page_alloc.c:1250 [inline] RIP: 0010:__free_frozen_pages+0xa92/0xce0 mm/page_alloc.c:2721 Code: 00 00 00 fc ff df 80 3c 08 00 74 08 48 89 df e8 d4 4d 0d 00 4c 0b 33 48 b8 00 00 00 00 00 fc ff df 48 8b 4c 24 30 80 3c 01 00 <74> 08 4c 89 ef e8 b4 4d 0d 00 48 b8 7c 00 00 00 80 ff ff ff 49 23 RSP: 0018:ffffc90003d9f8d0 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: ffffea000145faf8 RCX: 1ffffd400028bf59 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffea000145faf4 RBP: 0000000000000000 R08: ffffea000145faf7 R09: 1ffffd400028bf5e R10: dffffc0000000000 R11: fffff9400028bf5f R12: ffffea000145fac0 R13: ffffea000145fac8 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881260c1000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3548e3f440 CR3: 0000000032dd8000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: vfree+0x1a6/0x330 mm/vmalloc.c:3383 kcov_put kernel/kcov.c:439 [inline] kcov_close+0x28/0x50 kernel/kcov.c:535 __fput+0x449/0xa70 fs/file_table.c:465 task_work_run+0x1d1/0x260 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x8d6/0x2550 kernel/exit.c:953 do_group_exit+0x21c/0x2d0 kernel/exit.c:1102 get_signal+0x125e/0x1310 kernel/signal.c:3034 arch_do_signal_or_restart+0x95/0x780 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x8b/0x120 kernel/entry/common.c:218 do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f62f57907fc Code: Unable to access opcode bytes at 0x7f62f57907d2. RSP: 002b:00007ffefcc45790 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: 000000000000006c RBX: 00007f62f64e4620 RCX: 00007f62f57907fc RDX: 000000000000006c RSI: 00007f62f64e4670 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffefcc457e4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f62f64e4670 R15: 0000000000000000