INFO: task syz.1.90:6538 blocked for more than 143 seconds. Not tainted 6.15.0-rc7-syzkaller-00142-g4856ebd99715 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.90 state:D stack:24824 pid:6538 tgid:6537 ppid:5815 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x168f/0x4c70 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 rwsem_down_read_slowpath+0x552/0x880 kernel/locking/rwsem.c:1084 __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1526 __super_lock fs/super.c:58 [inline] super_lock+0x2a9/0x3b0 fs/super.c:120 super_lock_shared fs/super.c:139 [inline] iterate_supers+0x80/0x180 fs/super.c:931 ksys_sync+0x94/0x150 fs/sync.c:102 __ia32_sys_sync+0xe/0x20 fs/sync.c:113 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: 0033:0x7f9c8c18e969 RSP: 002b:00007f9c89ff6038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f9c8c3b5fa0 RCX: 00007f9c8c18e969 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f9c8c3b5fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f9c8c3b5fa0 R15: 00007ffdcea030f8 Showing all locks held in the system: 4 locks held by kworker/0:0/9: #0: ffff88801a080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801a080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffff8880b8823b08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39e/0x6d0 kernel/sched/psi.c:987 #2: ffff888055bfa538 (&idev->mc_lock){+.+.}-{4:4}, at: mld_ifc_work+0x2d/0xde0 net/ipv6/mcast.c:2701 #3: ffffffff99a8cc58 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0xbb/0x420 lib/debugobjects.c:818 5 locks held by kworker/u8:0/12: #0: ffff88801aef3948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801aef3948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc90000117c60 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000117c60 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffffffff8f2dbd50 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x145/0xbd0 net/core/net_namespace.c:608 #3: ffff88805450d4e8 (&wg->device_update_lock){+.+.}-{4:4}, at: wg_destruct+0x116/0x2f0 drivers/net/wireguard/device.c:249 #4: ffffffff8df439b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #4: ffffffff8df439b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998 1 lock held by khungtaskd/31: #0: ffffffff8df3dee0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3dee0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8df3dee0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764 3 locks held by kworker/1:1/53: #0: ffff88801a080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801a080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc90000be7c60 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000be7c60 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffffffff8df439b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #2: ffffffff8df439b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998 2 locks held by getty/5578: #0: ffff8880309a40a0 (&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 2 locks held by syz-executor/5819: 1 lock held by syz.1.90/6538: #0: ffff888011d9c0e0 (&type->s_umount_key#100){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888011d9c0e0 (&type->s_umount_key#100){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 1 lock held by syz.2.139/6901: #0: ffff888011d9c0e0 (&type->s_umount_key#100){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888011d9c0e0 (&type->s_umount_key#100){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 1 lock held by syz.0.208/7556: #0: ffff888011d9c0e0 (&type->s_umount_key#100){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888011d9c0e0 (&type->s_umount_key#100){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 1 lock held by syz.3.227/7793: #0: ffff888011d9c0e0 (&type->s_umount_key#100){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888011d9c0e0 (&type->s_umount_key#100){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 1 lock held by syz.4.300/8484: 4 locks held by syz.1.301/8488: #0: ffff8880505f4d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] #0: ffff8880505f4d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x1fe/0x500 net/bluetooth/hci_core.c:2678 #1: ffff8880505f4078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x66a/0x1330 net/bluetooth/hci_sync.c:5213 #2: ffffffff8f44e208 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2065 [inline] #2: ffffffff8f44e208 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x230 net/bluetooth/hci_conn.c:2534 #3: ffff8880604c7b38 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x70/0x680 net/bluetooth/l2cap_core.c:1762 1 lock held by dhcpcd/8521: #0: ffff88804c940258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1651 [inline] #0: ffff88804c940258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcd0 net/packet/af_packet.c:3252 1 lock held by dhcpcd-run-hook/8522: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc7-syzkaller-00142-g4856ebd99715 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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+0x711/0x8a0 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: 8528 Comm: syz-executor Not tainted 6.15.0-rc7-syzkaller-00142-g4856ebd99715 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:unwind_next_frame+0xc98/0x2390 arch/x86/kernel/unwind_orc.c:-1 Code: 8b 5c 24 70 4c 8b 6c 24 50 4c 8b 64 24 10 74 08 48 89 df e8 6a f1 ad 00 4c 89 23 ba 10 00 00 00 4c 89 ef 31 f6 e8 38 f3 ad 00 <48> 8b 14 24 e9 c5 04 00 00 4c 89 7c 24 28 48 89 5c 24 78 4d 8d 66 RSP: 0018:ffffc9000c006d38 EFLAGS: 00000246 RAX: ffffc9000c006eb8 RBX: ffffc9000c006ea0 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffc9000c006ec8 RBP: dffffc0000000000 R08: ffffc9000c006ec7 R09: 0000000000000000 R10: ffffc9000c006eb8 R11: fffff52001800dd9 R12: ffffc9000c006e68 R13: ffffc9000c006eb8 R14: ffffc9000c006e68 R15: ffffc9000c006eb0 FS: 000055556c724500(0000) GS:ffff8881260f6000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555c44f4e660 CR3: 000000003162e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4147 [inline] slab_alloc_node mm/slub.c:4196 [inline] kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4203 __kernfs_new_node+0xd7/0x7f0 fs/kernfs/dir.c:637 kernfs_new_node+0x102/0x210 fs/kernfs/dir.c:713 __kernfs_create_file+0x4b/0x2e0 fs/kernfs/file.c:1038 sysfs_add_file_mode_ns+0x238/0x300 fs/sysfs/file.c:319 create_files fs/sysfs/group.c:76 [inline] internal_create_group+0x66d/0x1110 fs/sysfs/group.c:183 internal_create_groups fs/sysfs/group.c:223 [inline] sysfs_create_groups+0x59/0x120 fs/sysfs/group.c:249 device_add_groups drivers/base/core.c:2839 [inline] device_add_attrs+0xe0/0x5a0 drivers/base/core.c:2903 device_add+0x496/0xb50 drivers/base/core.c:3646 netdev_register_kobject+0x156/0x2f0 net/core/net-sysfs.c:2336 register_netdevice+0x126c/0x1af0 net/core/dev.c:10999 __ip_tunnel_create+0x398/0x4c0 net/ipv4/ip_tunnel.c:268 ip_tunnel_init_net+0x2ba/0x800 net/ipv4/ip_tunnel.c:1161 vti_init_net+0x2f/0x100 net/ipv4/ip_vti.c:517 ops_init+0x35c/0x5c0 net/core/net_namespace.c:138 setup_net+0x238/0x830 net/core/net_namespace.c:364 copy_net_ns+0x32e/0x590 net/core/net_namespace.c:518 create_new_namespaces+0x3d3/0x700 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x11c/0x170 kernel/nsproxy.c:228 ksys_unshare+0x4c8/0x8c0 kernel/fork.c:3376 __do_sys_unshare kernel/fork.c:3447 [inline] __se_sys_unshare kernel/fork.c:3445 [inline] __x64_sys_unshare+0x38/0x50 kernel/fork.c:3445 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: 0033:0x7fc8ac390167 Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 10 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffcd9bafc28 EFLAGS: 00000202 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007fc8ac5b5f40 RCX: 00007fc8ac390167 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000 RBP: 00007fc8ac5b6738 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008 R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000