INFO: task kworker/1:6:380 blocked for more than 122 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:6 state:D stack:0 pid:380 tgid:380 ppid:2 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:6026 [inline] __schedule+0x1399/0x1fa0 kernel/sched/core.c:7880 __schedule_loop kernel/sched/core.c:7961 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7976 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8033 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rcu_barrier+0x4d/0x540 kernel/rcu/tree.c:4589 netdev_run_todo+0x118/0xce0 net/core/dev.c:10900 rtnl_unlock+0x12/0x20 net/core/rtnetlink.c:152 unregister_netdev+0x166/0x1d0 net/core/dev.c:11602 usbnet_disconnect+0xd5/0x3a0 drivers/net/usb/usbnet.c:1653 usb_unbind_interface+0x2a7/0xa30 drivers/usb/core/driver.c:462 device_remove drivers/base/dd.c:569 [inline] __device_release_driver drivers/base/dd.c:1272 [inline] device_release_driver_internal+0x4c5/0x790 drivers/base/dd.c:1295 device_release_driver+0x1d/0x30 drivers/base/dd.c:1318 bus_remove_device+0x359/0x380 drivers/base/bus.c:576 device_del+0x581/0xd00 drivers/base/core.c:3881 usb_disable_device+0x3af/0x770 drivers/usb/core/message.c:1476 usb_disconnect+0x322/0x930 drivers/usb/core/hub.c:2353 hub_port_connect drivers/usb/core/hub.c:5414 [inline] hub_port_connect_change drivers/usb/core/hub.c:5714 [inline] port_event drivers/usb/core/hub.c:5878 [inline] hub_event+0x1c7a/0x4700 drivers/usb/core/hub.c:5960 process_one_work kernel/workqueue.c:3261 [inline] process_scheduled_works+0x7d4/0x1020 kernel/workqueue.c:3342 worker_thread+0xc51/0x1370 kernel/workqueue.c:3423 kthread+0x2c9/0x370 kernel/kthread.c:389 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INFO: task syz.0.846:3125 blocked for more than 123 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.846 state:D stack:0 pid:3125 tgid:3121 ppid:294 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:6026 [inline] __schedule+0x1399/0x1fa0 kernel/sched/core.c:7880 __schedule_loop kernel/sched/core.c:7961 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7976 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8033 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rcu_barrier+0x4d/0x540 kernel/rcu/tree.c:4589 kvm_mmu_uninit_tdp_mmu+0x1df/0x210 arch/x86/kvm/mmu/tdp_mmu.c:51 kvm_mmu_uninit_vm+0x27/0x60 arch/x86/kvm/mmu/mmu.c:6572 kvm_arch_destroy_vm+0x398/0x420 arch/x86/kvm/x86.c:12971 kvm_destroy_vm virt/kvm/kvm_main.c:1355 [inline] kvm_put_kvm+0xb04/0x12c0 virt/kvm/kvm_main.c:1392 kvm_vm_release+0x47/0x70 virt/kvm/kvm_main.c:1415 __fput+0x1fe/0xa00 fs/file_table.c:429 ____fput+0x20/0x30 fs/file_table.c:457 task_work_run+0x1e5/0x260 kernel/task_work.c:246 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0x9ad/0x2720 kernel/exit.c:954 do_group_exit+0x229/0x2f0 kernel/exit.c:1096 get_signal+0x1398/0x14e0 kernel/signal.c:2933 arch_do_signal_or_restart+0xbc/0x760 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:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x57/0xb0 kernel/entry/common.c:218 ret_from_fork+0x3a/0xa0 arch/x86/kernel/process.c:162 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 RIP: 0033:0x7f764639dbc9 RSP: 002b:00007f76472521c0 EFLAGS: 00000206 ORIG_RAX: 00000000000001b3 RAX: 0000000000000000 RBX: 00007f7646359160 RCX: 00007f764639dbc9 RDX: 00007f7646359160 RSI: 0000000000000058 RDI: 00007ffe3821dc90 RBP: 00007f76472526c0 R08: 00007f76472526c0 R09: 00007ffe3821dd77 R10: 0000000000000008 R11: 0000000000000206 R12: ffffffffffffffe8 R13: 000000000000006e R14: 00007ffe3821dc90 R15: 00007ffe3821dd78 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 21e0851607c2bcce87f6d1c77002e5a32d0b18de Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:94 dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120 dump_stack+0x19/0x20 lib/dump_stack.c:129 nmi_cpu_backtrace+0x2ba/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline] watchdog+0xdad/0xf00 kernel/hung_task.c:423 kthread+0x2c9/0x370 kernel/kthread.c:389 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 20 Comm: rcuop/0 Not tainted syzkaller #0 21e0851607c2bcce87f6d1c77002e5a32d0b18de Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:__kasan_check_read+0x4/0x20 mm/kasan/shadow.c:30 Code: eb 0a 48 c7 c7 d2 e7 1c 87 48 89 de e8 65 63 24 ff 45 31 ff eb c9 b8 76 da c1 3e 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa <55> 48 89 e5 89 f6 48 8b 4d 08 31 d2 e8 9b e4 ff ff 5d c3 cc cc cc RSP: 0018:ffffc90000006f78 EFLAGS: 00000282 RAX: ffffffff847fb53f RBX: 0000000000000000 RCX: ffff888103664c00 RDX: 0000000000000100 RSI: 0000000000000008 RDI: ffff8881300380a8 RBP: ffffc90000007030 R08: ffff888103664c00 R09: 0000000000000002 R10: 0000000000000003 R11: 0000000000000100 R12: 1ffff11028eb822a R13: ffff8881475c1150 R14: ffff8881475c1140 R15: ffff8881300380a8 FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6025947e20 CR3: 000000014b148000 CR4: 00000000003526b0 Call Trace: netif_rx_internal+0xab/0x340 net/core/dev.c:5313 __netif_rx+0x24/0x230 net/core/dev.c:5333 veth_forward_skb drivers/net/veth.c:324 [inline] veth_xmit+0x42e/0xb20 drivers/net/veth.c:378 __netdev_start_xmit include/linux/netdevice.h:5008 [inline] netdev_start_xmit include/linux/netdevice.h:5017 [inline] xmit_one net/core/dev.c:3681 [inline] dev_hard_start_xmit+0x218/0x760 net/core/dev.c:3697 __dev_queue_xmit+0x1927/0x3680 net/core/dev.c:4537 dev_queue_xmit include/linux/netdevice.h:3141 [inline] br_dev_queue_push_xmit+0x55c/0x700 net/bridge/br_forward.c:53 NF_HOOK include/linux/netfilter.h:317 [inline] br_forward_finish net/bridge/br_forward.c:66 [inline] NF_HOOK include/linux/netfilter.h:317 [inline] __br_forward+0x25c/0x390 net/bridge/br_forward.c:115 deliver_clone net/bridge/br_forward.c:131 [inline] maybe_deliver net/bridge/br_forward.c:191 [inline] br_flood+0x50e/0x730 net/bridge/br_forward.c:237 br_handle_frame_finish+0x11eb/0x17a0 net/bridge/br_input.c:215 nf_hook_bridge_pre net/bridge/br_input.c:301 [inline] br_handle_frame+0x5a6/0xba0 net/bridge/br_input.c:424 __netif_receive_skb_core+0xfae/0x3ab0 net/core/dev.c:5683 __netif_receive_skb_one_core net/core/dev.c:5787 [inline] __netif_receive_skb net/core/dev.c:5902 [inline] process_backlog+0x3e5/0xad0 net/core/dev.c:6238 __napi_poll+0xd0/0x610 net/core/dev.c:6889 napi_poll net/core/dev.c:6958 [inline] net_rx_action+0x5ea/0xd80 net/core/dev.c:7080 handle_softirqs+0x1aa/0x630 kernel/softirq.c:621 __do_softirq+0xf/0x16 kernel/softirq.c:659 do_softirq+0xb8/0x110 kernel/softirq.c:503 __local_bh_enable_ip+0x74/0x80 kernel/softirq.c:430 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_do_batch+0x5d9/0xd40 kernel/rcu/tree.c:2594 nocb_cb_wait kernel/rcu/tree_nocb.h:923 [inline] rcu_nocb_cb_kthread+0x524/0xb30 kernel/rcu/tree_nocb.h:957 kthread+0x2c9/0x370 kernel/kthread.c:389 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 net_ratelimit: 80158 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:8e:4e:3e:b9:88:91, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:8e:4e:3e:b9:88:91, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) net_ratelimit: 76975 callbacks suppressed bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:8e:4e:3e:b9:88:91, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:8e:4e:3e:b9:88:91, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)