bisecting fixing commit since f6d5cb9e2c06f7d583dd9f4f7cca21d13d78c32a building syzkaller on abf9ba4fc75d9b29af15625d44dcfc1360fad3b7 testing commit f6d5cb9e2c06f7d583dd9f4f7cca21d13d78c32a with gcc (GCC) 8.4.1 20210217 kernel signature: f45edd307d63c20df98e7d245ce9e190b84f75c78fab554ba42a5d7901f33337 all runs: crashed: INFO: task hung in rtnl_lock testing current HEAD 2965db2e004cf9c92b87c1f559e9812c0ae878c1 testing commit 2965db2e004cf9c92b87c1f559e9812c0ae878c1 with gcc (GCC) 8.4.1 20210217 kernel signature: a13f558a32a42e8aaa0c9d498b07fd4deaf6035dba9cb993f6c65b8e2ef2d389 all runs: crashed: INFO: task hung in rtnl_lock revisions tested: 2, total time: 30m35.852342881s (build: 16m16.421547618s, test: 13m55.974261951s) the crash still happens on HEAD commit msg: Linux 4.19.188 crash: INFO: task hung in rtnl_lock Bluetooth: hci3: command 0x0406 tx timeout Bluetooth: hci1: command 0x0406 tx timeout Bluetooth: hci0: command 0x0406 tx timeout Bluetooth: hci4: command 0x0406 tx timeout Bluetooth: hci2: command 0x0406 tx timeout INFO: task kworker/1:1:25 blocked for more than 140 seconds. Not tainted 4.19.188-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:1 D25800 25 2 0x80000000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1005 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1075 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1090 rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 addrconf_dad_work+0xa1/0xf70 net/ipv6/addrconf.c:3989 process_one_work+0x7b9/0x15a0 kernel/workqueue.c:2152 worker_thread+0x85/0xb60 kernel/workqueue.c:2295 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 INFO: task kworker/0:2:2773 blocked for more than 140 seconds. Not tainted 4.19.188-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:2 D25960 2773 2 0x80000000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1005 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1075 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1090 rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 addrconf_dad_work+0xa1/0xf70 net/ipv6/addrconf.c:3989 process_one_work+0x7b9/0x15a0 kernel/workqueue.c:2152 worker_thread+0x85/0xb60 kernel/workqueue.c:2295 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 INFO: task kworker/1:2:3410 blocked for more than 140 seconds. Not tainted 4.19.188-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:2 D24936 3410 2 0x80000000 Workqueue: events_power_efficient crda_timeout_work Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1005 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1075 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1090 rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 crda_timeout_work+0x9/0x30 net/wireless/reg.c:511 process_one_work+0x7b9/0x15a0 kernel/workqueue.c:2152 worker_thread+0x85/0xb60 kernel/workqueue.c:2295 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 INFO: task kworker/1:3:7113 blocked for more than 140 seconds. Not tainted 4.19.188-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:3 D26264 7113 2 0x80000000 Workqueue: events_power_efficient reg_check_chans_work Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1005 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1075 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1090 rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 reg_check_chans_work+0x73/0xb20 net/wireless/reg.c:2189 process_one_work+0x7b9/0x15a0 kernel/workqueue.c:2152 worker_thread+0x85/0xb60 kernel/workqueue.c:2295 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 INFO: task syz-executor.1:7319 blocked for more than 140 seconds. Not tainted 4.19.188-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D25640 7319 5884 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1005 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1075 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1090 rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 load_metaops_and_vet net/sched/act_ife.c:281 [inline] populate_metalist net/sched/act_ife.c:456 [inline] tcf_ife_init+0xfb5/0x1590 net/sched/act_ife.c:580 tcf_action_init_1+0x8c6/0xbc0 net/sched/act_api.c:870 tcf_action_init+0x178/0x300 net/sched/act_api.c:936 tcf_action_add+0xf2/0x320 net/sched/act_api.c:1317 tc_ctl_action+0x28d/0x3d0 net/sched/act_api.c:1372 rtnetlink_rcv_msg+0x34f/0x950 net/core/rtnetlink.c:4778 netlink_rcv_skb+0x13e/0x3d0 net/netlink/af_netlink.c:2455 rtnetlink_rcv+0x10/0x20 net/core/rtnetlink.c:4796 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x443/0x660 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x667/0xc60 net/netlink/af_netlink.c:1909 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:632 ___sys_sendmsg+0x647/0x950 net/socket.c:2115 __sys_sendmsg+0xd9/0x180 net/socket.c:2153 __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2160 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465109 Code: Bad RIP value. RSP: 002b:00007f47da791188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000055cf00 RCX: 0000000000465109 RDX: 0000000000000000 RSI: 0000000020000100 RDI: 0000000000000003 RBP: 00000000004af711 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000055cf00 R13: 00007fff327207cf R14: 00007f47da791300 R15: 0000000000022000 INFO: task syz-executor.1:7352 blocked for more than 140 seconds. Not tainted 4.19.188-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28440 7352 5884 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1005 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1075 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1090 rtnl_lock net/core/rtnetlink.c:77 [inline] rtnetlink_rcv_msg+0x301/0x950 net/core/rtnetlink.c:4775 netlink_rcv_skb+0x13e/0x3d0 net/netlink/af_netlink.c:2455 rtnetlink_rcv+0x10/0x20 net/core/rtnetlink.c:4796 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x443/0x660 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x667/0xc60 net/netlink/af_netlink.c:1909 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:632 ___sys_sendmsg+0x647/0x950 net/socket.c:2115 __sys_sendmsg+0xd9/0x180 net/socket.c:2153 __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2160 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465109 Code: Bad RIP value. RSP: 002b:00007f47da74f188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000055d040 RCX: 0000000000465109 RDX: 0000000000000000 RSI: 0000000020000100 RDI: 0000000000000003 RBP: 00000000004af711 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000055d040 R13: 00007fff327207cf R14: 00007f47da74f300 R15: 0000000000022000 INFO: task syz-executor.3:7338 blocked for more than 140 seconds. Not tainted 4.19.188-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D25640 7338 5893 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1005 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1075 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1090 rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 load_metaops_and_vet net/sched/act_ife.c:281 [inline] populate_metalist net/sched/act_ife.c:456 [inline] tcf_ife_init+0xfb5/0x1590 net/sched/act_ife.c:580 tcf_action_init_1+0x8c6/0xbc0 net/sched/act_api.c:870 tcf_action_init+0x178/0x300 net/sched/act_api.c:936 tcf_action_add+0xf2/0x320 net/sched/act_api.c:1317 tc_ctl_action+0x28d/0x3d0 net/sched/act_api.c:1372 rtnetlink_rcv_msg+0x34f/0x950 net/core/rtnetlink.c:4778 netlink_rcv_skb+0x13e/0x3d0 net/netlink/af_netlink.c:2455 rtnetlink_rcv+0x10/0x20 net/core/rtnetlink.c:4796 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x443/0x660 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x667/0xc60 net/netlink/af_netlink.c:1909 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:632 ___sys_sendmsg+0x647/0x950 net/socket.c:2115 __sys_sendmsg+0xd9/0x180 net/socket.c:2153 __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2160 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465109 Code: Bad RIP value. RSP: 002b:00007f8827bf7188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000055cf00 RCX: 0000000000465109 RDX: 0000000000000000 RSI: 0000000020000100 RDI: 0000000000000003 RBP: 00000000004af711 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000055cf00 R13: 00007ffe366b3edf R14: 00007f8827bf7300 R15: 0000000000022000 INFO: task syz-executor.3:7346 blocked for more than 140 seconds. Not tainted 4.19.188-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D28440 7346 5893 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1005 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1075 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1090 rtnl_lock net/core/rtnetlink.c:77 [inline] rtnetlink_rcv_msg+0x301/0x950 net/core/rtnetlink.c:4775 netlink_rcv_skb+0x13e/0x3d0 net/netlink/af_netlink.c:2455 rtnetlink_rcv+0x10/0x20 net/core/rtnetlink.c:4796 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x443/0x660 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x667/0xc60 net/netlink/af_netlink.c:1909 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:632 ___sys_sendmsg+0x647/0x950 net/socket.c:2115 __sys_sendmsg+0xd9/0x180 net/socket.c:2153 __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2160 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465109 Code: Bad RIP value. RSP: 002b:00007f8827bd6188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000055cfa0 RCX: 0000000000465109 RDX: 0000000000000000 RSI: 0000000020000100 RDI: 0000000000000004 RBP: 00000000004af711 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000055cfa0 R13: 00007ffe366b3edf R14: 00007f8827bd6300 R15: 0000000000022000 INFO: task syz-executor.3:7355 blocked for more than 140 seconds. Not tainted 4.19.188-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D27896 7355 5893 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1005 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1075 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1090 rtnl_lock net/core/rtnetlink.c:77 [inline] rtnetlink_rcv_msg+0x301/0x950 net/core/rtnetlink.c:4775 netlink_rcv_skb+0x13e/0x3d0 net/netlink/af_netlink.c:2455 rtnetlink_rcv+0x10/0x20 net/core/rtnetlink.c:4796 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x443/0x660 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x667/0xc60 net/netlink/af_netlink.c:1909 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:632 ___sys_sendmsg+0x647/0x950 net/socket.c:2115 __sys_sendmsg+0xd9/0x180 net/socket.c:2153 __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2160 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465109 Code: Bad RIP value. RSP: 002b:00007f8827bb5188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000055d040 RCX: 0000000000465109 RDX: 0000000000000000 RSI: 0000000020000100 RDI: 0000000000000003 RBP: 00000000004af711 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000055d040 R13: 00007ffe366b3edf R14: 00007f8827bb5300 R15: 0000000000022000 INFO: task syz-executor.2:7337 blocked for more than 140 seconds. Not tainted 4.19.188-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D25640 7337 5889 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1005 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1075 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1090 rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 load_metaops_and_vet net/sched/act_ife.c:281 [inline] populate_metalist net/sched/act_ife.c:456 [inline] tcf_ife_init+0xfb5/0x1590 net/sched/act_ife.c:580 tcf_action_init_1+0x8c6/0xbc0 net/sched/act_api.c:870 tcf_action_init+0x178/0x300 net/sched/act_api.c:936 tcf_action_add+0xf2/0x320 net/sched/act_api.c:1317 tc_ctl_action+0x28d/0x3d0 net/sched/act_api.c:1372 rtnetlink_rcv_msg+0x34f/0x950 net/core/rtnetlink.c:4778 netlink_rcv_skb+0x13e/0x3d0 net/netlink/af_netlink.c:2455 rtnetlink_rcv+0x10/0x20 net/core/rtnetlink.c:4796 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x443/0x660 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x667/0xc60 net/netlink/af_netlink.c:1909 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:632 ___sys_sendmsg+0x647/0x950 net/socket.c:2115 __sys_sendmsg+0xd9/0x180 net/socket.c:2153 __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2160 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x465109 Code: Bad RIP value. RSP: 002b:00007f98db21c188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000055cf00 RCX: 0000000000465109 RDX: 0000000000000000 RSI: 0000000020000100 RDI: 0000000000000003 RBP: 00000000004af711 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000055cf00 R13: 00007ffea6c7219f R14: 00007f98db21c300 R15: 0000000000022000 Showing all locks held in the system: 3 locks held by kworker/1:1/25: #0: 00000000e87db128 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: process_one_work+0x6e8/0x15a0 kernel/workqueue.c:2123 #1: 00000000b57c8b91 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}, at: process_one_work+0x71b/0x15a0 kernel/workqueue.c:2127 #2: 00000000fb886120 (rtnl_mutex){+.+.}, at: rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 1 lock held by khungtaskd/1087: #0: 000000007413a426 (rcu_read_lock){....}, at: debug_show_all_locks+0x5b/0x27a kernel/locking/lockdep.c:4442 3 locks held by kworker/0:2/2773: #0: 00000000e87db128 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: process_one_work+0x6e8/0x15a0 kernel/workqueue.c:2123 #1: 00000000d8b8ef24 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}, at: process_one_work+0x71b/0x15a0 kernel/workqueue.c:2127 #2: 00000000fb886120 (rtnl_mutex){+.+.}, at: rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 3 locks held by kworker/1:2/3410: #0: 000000006aef0186 ((wq_completion)"events_power_efficient"){+.+.}, at: process_one_work+0x6e8/0x15a0 kernel/workqueue.c:2123 #1: 00000000cf0866e4 ((crda_timeout).work){+.+.}, at: process_one_work+0x71b/0x15a0 kernel/workqueue.c:2127 #2: 00000000fb886120 (rtnl_mutex){+.+.}, at: rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 1 lock held by in:imklog/5562: #0: 0000000005e105d1 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xa7/0xd0 fs/file.c:767 3 locks held by kworker/1:3/7113: #0: 000000006aef0186 ((wq_completion)"events_power_efficient"){+.+.}, at: process_one_work+0x6e8/0x15a0 kernel/workqueue.c:2123 #1: 00000000a5cb23b8 ((reg_check_chans).work){+.+.}, at: process_one_work+0x71b/0x15a0 kernel/workqueue.c:2127 #2: 00000000fb886120 (rtnl_mutex){+.+.}, at: rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 1 lock held by syz-executor.1/7319: #0: 00000000fb886120 (rtnl_mutex){+.+.}, at: rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 1 lock held by syz-executor.1/7339: 1 lock held by syz-executor.1/7352: #0: 00000000fb886120 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 00000000fb886120 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x301/0x950 net/core/rtnetlink.c:4775 1 lock held by syz-executor.3/7338: #0: 00000000fb886120 (rtnl_mutex){+.+.}, at: rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 1 lock held by syz-executor.3/7346: #0: 00000000fb886120 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 00000000fb886120 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x301/0x950 net/core/rtnetlink.c:4775 1 lock held by syz-executor.3/7355: #0: 00000000fb886120 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 00000000fb886120 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x301/0x950 net/core/rtnetlink.c:4775 1 lock held by syz-executor.2/7337: #0: 00000000fb886120 (rtnl_mutex){+.+.}, at: rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 1 lock held by syz-executor.2/7347: #0: 00000000fb886120 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 00000000fb886120 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x301/0x950 net/core/rtnetlink.c:4775 1 lock held by syz-executor.2/7354: #0: 00000000fb886120 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 00000000fb886120 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x301/0x950 net/core/rtnetlink.c:4775 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1087 Comm: khungtaskd Not tainted 4.19.188-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x17c/0x226 lib/dump_stack.c:118 nmi_cpu_backtrace.cold.0+0x3c/0x78 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0xf5/0x120 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x5c3/0xb40 kernel/hung_task.c:287 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 2399 Comm: kworker/u4:4 Not tainted 4.19.188-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:mark_lock+0xaa/0x12f0 kernel/locking/lockdep.c:3105 Code: 00 00 49 81 ec 50 01 00 00 49 81 c4 c0 c8 cb 89 49 8d 7c 24 30 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 05 0e 00 00 4d 85 6c 24 30 74 58 b8 01 00 00 00 48 83 c4 20 RSP: 0018:ffff8881ea4379a8 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffff8881ea4c2dd8 RCX: 1ffff1103d4985bf RDX: 1ffffffff13aa40a RSI: ffff8881ea4c2dd8 RDI: ffffffff89d52050 RBP: ffff8881ea4379f0 R08: ffff8881ea4c2df8 R09: 0000000000000002 R10: ffff8881ea4c2dd8 R11: ffff8881ea4c2d74 R12: ffffffff89d52020 R13: 0000000000000100 R14: 0000000000000008 R15: ffff8881ea4c2500 FS: 0000000000000000(0000) GS:ffff8881f6900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055e53612f718 CR3: 000000000846d006 CR4: 00000000001606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_acquire+0x764/0x47c0 kernel/locking/lockdep.c:3376 lock_acquire+0x180/0x3a0 kernel/locking/lockdep.c:3907 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:168 spin_lock_bh include/linux/spinlock.h:334 [inline] batadv_nc_purge_paths+0xc0/0x2c0 net/batman-adv/network-coding.c:453 batadv_nc_worker+0x1f3/0x630 net/batman-adv/network-coding.c:731 process_one_work+0x7b9/0x15a0 kernel/workqueue.c:2152 worker_thread+0x85/0xb60 kernel/workqueue.c:2295 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415