====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Tainted: G L ------------------------------------------------------ syz.4.465/7345 is trying to acquire lock: ffff0000dbc40e78 (&dev_instance_lock_key#23){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2861 [inline] ffff0000dbc40e78 (&dev_instance_lock_key#23){+.+.}-{4:4}, at: ipvlan_uninit+0x128/0x28c drivers/net/ipvlan/ipvlan_main.c:228 but task is already holding lock: ffff0000f7ca48c0 (&port->pnodes_lock){+.+.}-{4:4}, at: ipvlan_device_event+0x434/0xcc0 drivers/net/ipvlan/ipvlan_main.c:810 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&port->pnodes_lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:646 [inline] __mutex_lock+0x164/0xf14 kernel/locking/mutex.c:821 mutex_lock_nested+0x24/0x30 kernel/locking/mutex.c:874 ipvlan_device_event+0x434/0xcc0 drivers/net/ipvlan/ipvlan_main.c:810 notifier_call_chain+0x1a4/0x624 kernel/notifier.c:85 raw_notifier_call_chain+0x3c/0x50 kernel/notifier.c:453 call_netdevice_notifiers_info+0xb8/0x120 net/core/dev.c:2275 call_netdevice_notifiers_extack net/core/dev.c:2313 [inline] call_netdevice_notifiers net/core/dev.c:2327 [inline] __dev_close_many+0xf8/0x648 net/core/dev.c:1769 netif_close_many+0x1d8/0x51c net/core/dev.c:1824 netif_close_many_and_unlock+0x38/0x15c net/core/dev.c:12411 unregister_netdevice_many_notify+0x5a4/0x1760 net/core/dev.c:12481 unregister_netdevice_many net/core/dev.c:12589 [inline] unregister_netdevice_queue+0x274/0x30c net/core/dev.c:12390 unregister_netdevice include/linux/netdevice.h:3487 [inline] nsim_destroy+0x248/0x5f8 drivers/net/netdevsim/netdev.c:1198 __nsim_dev_port_del+0x13c/0x1ec drivers/net/netdevsim/dev.c:1472 nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1486 [inline] nsim_dev_reload_destroy+0x13c/0x210 drivers/net/netdevsim/dev.c:1710 nsim_dev_reload_down+0x9c/0xd0 drivers/net/netdevsim/dev.c:963 devlink_reload+0x19c/0x64c net/devlink/dev.c:462 devlink_nl_reload_doit+0x8c0/0xa0c net/devlink/dev.c:586 genl_family_rcv_msg_doit+0x1e4/0x2d4 net/netlink/genetlink.c:1114 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline] genl_rcv_msg+0x43c/0x620 net/netlink/genetlink.c:1209 netlink_rcv_skb+0x238/0x414 net/netlink/af_netlink.c:2556 genl_rcv+0x38/0x50 net/netlink/genetlink.c:1218 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x600/0x7f8 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x648/0x948 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec net/socket.c:800 [inline] __sock_sendmsg+0xc8/0x17c net/socket.c:815 ____sys_sendmsg+0x3d0/0x6c8 net/socket.c:2713 ___sys_sendmsg+0x198/0x224 net/socket.c:2767 __sys_sendmsg+0x158/0x204 net/socket.c:2799 __do_sys_sendmsg net/socket.c:2804 [inline] __se_sys_sendmsg net/socket.c:2802 [inline] __arm64_sys_sendmsg+0x88/0x9c net/socket.c:2802 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140 el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:758 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:777 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:590 -> #0 (&dev_instance_lock_key#23){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3181 [inline] check_prevs_add kernel/locking/lockdep.c:3300 [inline] validate_chain kernel/locking/lockdep.c:3924 [inline] __lock_acquire+0x1600/0x2a6c kernel/locking/lockdep.c:5254 lock_acquire+0x150/0x370 kernel/locking/lockdep.c:5908 __mutex_lock_common kernel/locking/mutex.c:646 [inline] __mutex_lock+0x164/0xf14 kernel/locking/mutex.c:821 mutex_lock_nested+0x24/0x30 kernel/locking/mutex.c:874 netdev_lock include/linux/netdevice.h:2861 [inline] ipvlan_uninit+0x128/0x28c drivers/net/ipvlan/ipvlan_main.c:228 unregister_netdevice_many_notify+0x1188/0x1760 net/core/dev.c:12537 unregister_netdevice_many+0x28/0x38 net/core/dev.c:12589 ipvlan_device_event+0xbe4/0xcc0 drivers/net/ipvlan/ipvlan_main.c:851 notifier_call_chain+0x1a4/0x624 kernel/notifier.c:85 raw_notifier_call_chain+0x3c/0x50 kernel/notifier.c:453 call_netdevice_notifiers_info+0xb8/0x120 net/core/dev.c:2275 call_netdevice_notifiers_extack net/core/dev.c:2313 [inline] call_netdevice_notifiers net/core/dev.c:2327 [inline] unregister_netdevice_many_notify+0xf24/0x1760 net/core/dev.c:12518 unregister_netdevice_many net/core/dev.c:12589 [inline] unregister_netdevice_queue+0x274/0x30c net/core/dev.c:12390 unregister_netdevice include/linux/netdevice.h:3487 [inline] nsim_destroy+0x248/0x5f8 drivers/net/netdevsim/netdev.c:1198 __nsim_dev_port_del+0x13c/0x1ec drivers/net/netdevsim/dev.c:1472 nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1486 [inline] nsim_dev_reload_destroy+0x13c/0x210 drivers/net/netdevsim/dev.c:1710 nsim_dev_reload_down+0x9c/0xd0 drivers/net/netdevsim/dev.c:963 devlink_reload+0x19c/0x64c net/devlink/dev.c:462 devlink_nl_reload_doit+0x8c0/0xa0c net/devlink/dev.c:586 genl_family_rcv_msg_doit+0x1e4/0x2d4 net/netlink/genetlink.c:1114 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline] genl_rcv_msg+0x43c/0x620 net/netlink/genetlink.c:1209 netlink_rcv_skb+0x238/0x414 net/netlink/af_netlink.c:2556 genl_rcv+0x38/0x50 net/netlink/genetlink.c:1218 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x600/0x7f8 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x648/0x948 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec net/socket.c:800 [inline] __sock_sendmsg+0xc8/0x17c net/socket.c:815 ____sys_sendmsg+0x3d0/0x6c8 net/socket.c:2713 ___sys_sendmsg+0x198/0x224 net/socket.c:2767 __sys_sendmsg+0x158/0x204 net/socket.c:2799 __do_sys_sendmsg net/socket.c:2804 [inline] __se_sys_sendmsg net/socket.c:2802 [inline] __arm64_sys_sendmsg+0x88/0x9c net/socket.c:2802 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140 el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:758 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:777 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:590 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&port->pnodes_lock); lock(&dev_instance_lock_key#23); lock(&port->pnodes_lock); lock(&dev_instance_lock_key#23); *** DEADLOCK *** locks held by syz.4.465/7345: 5, last CPU#1: #0: ffff800089f51268 (cb_lock){++++}-{4:4}, at: genl_rcv+0x28/0x50 net/netlink/genetlink.c:1217 #1: ffff0000f26d8128 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline] #1: ffff0000f26d8128 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:124 [inline] #1: ffff0000f26d8128 (&dev->mutex){....}-{4:4}, at: devlink_get_from_attrs_lock+0x2b8/0x3f0 net/devlink/netlink.c:235 #2: ffff0000dbc1f258 (&devlink->lock_key#5){+.+.}-{4:4}, at: devl_lock+0x24/0x34 net/devlink/core.c:308 #3: ffff800089ee9d40 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80 #4: ffff0000f7ca48c0 (&port->pnodes_lock){+.+.}-{4:4}, at: ipvlan_device_event+0x434/0xcc0 drivers/net/ipvlan/ipvlan_main.c:810 stack backtrace: CPU: 1 UID: 0 PID: 7345 Comm: syz.4.465 Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/07/2026 Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C) __dump_stack+0x30/0x40 lib/dump_stack.c:94 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120 dump_stack+0x1c/0x28 lib/dump_stack.c:129 print_circular_bug+0x328/0x330 kernel/locking/lockdep.c:2059 check_noncircular+0x158/0x174 kernel/locking/lockdep.c:2191 check_prev_add kernel/locking/lockdep.c:3181 [inline] check_prevs_add kernel/locking/lockdep.c:3300 [inline] validate_chain kernel/locking/lockdep.c:3924 [inline] __lock_acquire+0x1600/0x2a6c kernel/locking/lockdep.c:5254 lock_acquire+0x150/0x370 kernel/locking/lockdep.c:5908 __mutex_lock_common kernel/locking/mutex.c:646 [inline] __mutex_lock+0x164/0xf14 kernel/locking/mutex.c:821 mutex_lock_nested+0x24/0x30 kernel/locking/mutex.c:874 netdev_lock include/linux/netdevice.h:2861 [inline] ipvlan_uninit+0x128/0x28c drivers/net/ipvlan/ipvlan_main.c:228 unregister_netdevice_many_notify+0x1188/0x1760 net/core/dev.c:12537 unregister_netdevice_many+0x28/0x38 net/core/dev.c:12589 ipvlan_device_event+0xbe4/0xcc0 drivers/net/ipvlan/ipvlan_main.c:851 notifier_call_chain+0x1a4/0x624 kernel/notifier.c:85 raw_notifier_call_chain+0x3c/0x50 kernel/notifier.c:453 call_netdevice_notifiers_info+0xb8/0x120 net/core/dev.c:2275 call_netdevice_notifiers_extack net/core/dev.c:2313 [inline] call_netdevice_notifiers net/core/dev.c:2327 [inline] unregister_netdevice_many_notify+0xf24/0x1760 net/core/dev.c:12518 unregister_netdevice_many net/core/dev.c:12589 [inline] unregister_netdevice_queue+0x274/0x30c net/core/dev.c:12390 unregister_netdevice include/linux/netdevice.h:3487 [inline] nsim_destroy+0x248/0x5f8 drivers/net/netdevsim/netdev.c:1198 __nsim_dev_port_del+0x13c/0x1ec drivers/net/netdevsim/dev.c:1472 nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1486 [inline] nsim_dev_reload_destroy+0x13c/0x210 drivers/net/netdevsim/dev.c:1710 nsim_dev_reload_down+0x9c/0xd0 drivers/net/netdevsim/dev.c:963 devlink_reload+0x19c/0x64c net/devlink/dev.c:462 devlink_nl_reload_doit+0x8c0/0xa0c net/devlink/dev.c:586 genl_family_rcv_msg_doit+0x1e4/0x2d4 net/netlink/genetlink.c:1114 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline] genl_rcv_msg+0x43c/0x620 net/netlink/genetlink.c:1209 netlink_rcv_skb+0x238/0x414 net/netlink/af_netlink.c:2556 genl_rcv+0x38/0x50 net/netlink/genetlink.c:1218 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x600/0x7f8 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x648/0x948 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec net/socket.c:800 [inline] __sock_sendmsg+0xc8/0x17c net/socket.c:815 ____sys_sendmsg+0x3d0/0x6c8 net/socket.c:2713 ___sys_sendmsg+0x198/0x224 net/socket.c:2767 __sys_sendmsg+0x158/0x204 net/socket.c:2799 __do_sys_sendmsg net/socket.c:2804 [inline] __se_sys_sendmsg net/socket.c:2802 [inline] __arm64_sys_sendmsg+0x88/0x9c net/socket.c:2802 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140 el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:758 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:777 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:590 netdevsim netdevsim4 netdevsim3 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim4 netdevsim2 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim4 netdevsim1 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim4 netdevsim0 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0