INFO: task syz.0.16:6799 blocked for more than 143 seconds. Not tainted 6.17.0-rc1-syzkaller-g8f5ae30d69d7 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.16 state:D stack:26904 pid:6799 tgid:6796 ppid:6631 task_flags:0x400740 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7058 schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common+0x2fc/0x4e0 kernel/sched/completion.c:121 wait_for_common kernel/sched/completion.c:132 [inline] wait_for_completion_state+0x1c/0x40 kernel/sched/completion.c:269 coredump_wait fs/coredump.c:534 [inline] vfs_coredump+0x981/0x56d0 fs/coredump.c:1129 get_signal+0x22e3/0x26d0 kernel/signal.c:3019 arch_do_signal_or_restart+0x8f/0x790 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x84/0x110 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x3f6/0x490 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fbd7398cda9 RSP: 002b:00007fbd747070e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007fbd73ba6088 RCX: 00007fbd7398cda9 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fbd73ba608c RBP: 00007fbd73ba6080 R08: 00007fbd74729000 R09: 0000000000000000 R10: 0000000000000080 R11: 0000000000000246 R12: 00007fbd73ba608c R13: 0000000000000000 R14: 00007ffc01a5ae10 R15: 00007ffc01a5aef8 INFO: task syz.1.17:6815 blocked for more than 146 seconds. Not tainted 6.17.0-rc1-syzkaller-g8f5ae30d69d7 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.17 state:D stack:26904 pid:6815 tgid:6813 ppid:6634 task_flags:0x400740 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7058 schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common+0x2fc/0x4e0 kernel/sched/completion.c:121 wait_for_common kernel/sched/completion.c:132 [inline] wait_for_completion_state+0x1c/0x40 kernel/sched/completion.c:269 coredump_wait fs/coredump.c:534 [inline] vfs_coredump+0x981/0x56d0 fs/coredump.c:1129 get_signal+0x22e3/0x26d0 kernel/signal.c:3019 arch_do_signal_or_restart+0x8f/0x790 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x84/0x110 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x3f6/0x490 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7cc618cda9 RSP: 002b:00007f7cc6f830e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007f7cc63a6088 RCX: 00007f7cc618cda9 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f7cc63a608c RBP: 00007f7cc63a6080 R08: 00007f7cc6fa5000 R09: 0000000000000000 R10: 0000000000000080 R11: 0000000000000246 R12: 00007f7cc63a608c R13: 0000000000000000 R14: 00007ffcd0fbc620 R15: 00007ffcd0fbc708 Showing all locks held in the system: 3 locks held by kworker/u8:0/12: #0: ffff88803064f948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc90000117d10 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffffffff903855c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff903855c8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x120/0x14e0 net/ipv6/addrconf.c:4194 5 locks held by kworker/u8:1/13: 1 lock held by khungtaskd/31: #0: ffffffff8e5c1060 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5c1060 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e5c1060 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775 5 locks held by kworker/u8:4/59: #0: ffff88801c6fe948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc9000210fd10 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffffffff9036f370 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xad/0x890 net/core/net_namespace.c:658 #3: ffffffff903855c8 (rtnl_mutex){+.+.}-{4:4}, at: ops_exit_rtnl_list net/core/net_namespace.c:172 [inline] #3: ffffffff903855c8 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x7e9/0xab0 net/core/net_namespace.c:247 #4: ffffffff8e5cc5f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:343 2 locks held by kworker/0:2/982: #0: ffff88801b880d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc90003777d10 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 1 lock held by dhcpcd/5527: #0: ffffffff903855c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff903855c8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_delroute+0x102/0x3a0 net/ipv4/fib_frontend.c:887 2 locks held by getty/5622: #0: ffff8880354600a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 3 locks held by kworker/1:4/6698: #0: ffff88801b880d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc90002fd7d10 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffffffff903855c8 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 1 lock held by syz.2.18/6808: #0: ffffffff903855c8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff903855c8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3433 5 locks held by syz.1.17/6815: #0: ffff88803119cdc0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close+0x26/0x90 net/bluetooth/hci_core.c:499 #1: ffff88803119c0b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x3ae/0x11d0 net/bluetooth/hci_sync.c:5282 #2: ffffffff905ed5a8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2062 [inline] #2: ffffffff905ed5a8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xbb/0x260 net/bluetooth/hci_conn.c:2564 #3: ffff888022ba1b38 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x80/0x730 net/bluetooth/l2cap_core.c:1762 #4: ffffffff8e5cc5f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:343 3 locks held by kworker/u8:8/7004: #0: ffff88801b889148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc9000421fd10 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 #2: ffffffff903855c8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0x51/0xc0 net/core/link_watch.c:303 1 lock held by syz-executor/7403: #0: ffffffff903855c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff903855c8 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_newaddr+0x4e4/0x1c70 net/ipv6/addrconf.c:5027 7 locks held by syz-executor/7434: #0: ffff888025006428 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738 #1: ffff88804c3b0488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x510 fs/kernfs/file.c:325 #2: ffff88802855b008 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b2/0x510 fs/kernfs/file.c:326 #3: ffffffff8f8f5ac8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:234 #4: ffff88807d84d0e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #4: ffff88807d84d0e8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1096 [inline] #4: ffff88807d84d0e8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xa4/0x620 drivers/base/dd.c:1294 #5: ffff88807d84f250 (&devlink->lock_key#6){+.+.}-{4:4}, at: nsim_drv_remove+0x4a/0x1d0 drivers/net/netdevsim/dev.c:1721 #6: ffffffff903855c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #6: ffffffff903855c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x146/0x360 net/core/dev.c:2142 4 locks held by syz-executor/7447: #0: ffff888025006428 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738 #1: ffff888062861c88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x510 fs/kernfs/file.c:325 #2: ffff88802855b008 (kn->active#58){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b2/0x510 fs/kernfs/file.c:326 #3: ffffffff8f8f5ac8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:234 2 locks held by syz-executor/7453: #0: ffffffff8f6e2480 (&ops->srcu#2){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #0: ffffffff8f6e2480 (&ops->srcu#2){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #0: ffffffff8f6e2480 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x113/0x2c0 net/core/rtnetlink.c:574 #1: ffffffff903855c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff903855c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff903855c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x600/0x2000 net/core/rtnetlink.c:4056 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.17.0-rc1-syzkaller-g8f5ae30d69d7 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xf0e/0x1260 kernel/hung_task.c:491 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 7343 Comm: syz.8.25 Not tainted 6.17.0-rc1-syzkaller-g8f5ae30d69d7 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:36 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:139 [inline] RIP: 0010:wrmsrq arch/x86/include/asm/msr.h:199 [inline] RIP: 0010:native_x2apic_icr_write arch/x86/include/asm/apic.h:233 [inline] RIP: 0010:__x2apic_send_IPI_dest arch/x86/kernel/apic/x2apic_phys.c:113 [inline] RIP: 0010:x2apic_send_IPI+0x9a/0xe0 arch/x86/kernel/apic/x2apic_phys.c:50 Code: 8b 13 0f ae f0 0f ae e8 b9 00 04 00 00 41 83 fc 02 44 89 e0 48 0f 44 c1 48 c1 e2 20 b9 30 08 00 00 48 09 d0 48 c1 ea 20 0f 30 <66> 90 5b 5d 41 5c e9 1b de 29 0a 5b 31 d2 5d 48 89 c6 bf 30 08 00 RSP: 0018:ffffc9000aad79c8 EFLAGS: 00000246 RAX: 00000000000000fb RBX: ffff8880b84201b4 RCX: 0000000000000830 RDX: 0000000000000000 RSI: 00000000000000fb RDI: ffffffff8df57e60 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 00000000000000fb R13: 1ffff9200155af3f R14: 1ffff9200155af01 R15: 0000000000000000 FS: 00007f205486e6c0(0000) GS:ffff8881247c6000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000008ab000 CR3: 00000000328f0000 CR4: 00000000003526f0 Call Trace: arch_send_call_function_single_ipi arch/x86/include/asm/smp.h:95 [inline] send_call_function_single_ipi kernel/smp.c:120 [inline] __smp_call_single_queue+0x28c/0x2f0 kernel/smp.c:413 generic_exec_single+0xb4/0x390 kernel/smp.c:450 smp_call_function_single_async+0x68/0xd0 kernel/smp.c:732 cpuid_read+0x28b/0x360 arch/x86/kernel/cpuid.c:83 do_loop_readv_writev fs/read_write.c:847 [inline] do_loop_readv_writev fs/read_write.c:835 [inline] vfs_readv+0x5be/0x8b0 fs/read_write.c:1020 do_readv+0x132/0x340 fs/read_write.c:1080 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x490 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f205398cda9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 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:00007f205486e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000013 RAX: ffffffffffffffda RBX: 00007f2053ba5fa0 RCX: 00007f205398cda9 RDX: 0000000000000006 RSI: 0000000020000000 RDI: 0000000000000003 RBP: 00007f2053a0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f2053ba5fa0 R15: 00007ffe043c23c8