bisecting fixing commit since ad326970d25cc85128cd22d62398751ad072efff building syzkaller on a1839e81524f4e427a4b57bca0e4633d459d3d18 testing commit ad326970d25cc85128cd22d62398751ad072efff with gcc (GCC) 8.1.0 kernel signature: 9707ab57b9664cfe9ca55ec1f44af36e8e6c12226cf613b98583bed87d6a1afd run #0: crashed: KASAN: wild-memory-access Write in rhashtable_free_and_destroy run #1: crashed: BUG: unable to handle kernel NULL pointer dereference in rhashtable_free_and_destroy run #2: crashed: BUG: unable to handle kernel NULL pointer dereference in rhashtable_free_and_destroy run #3: crashed: general protection fault in get_work_pool run #4: crashed: general protection fault in get_work_pool_id run #5: crashed: KASAN: wild-memory-access Write in rhashtable_free_and_destroy run #6: crashed: BUG: unable to handle kernel NULL pointer dereference in rhashtable_free_and_destroy run #7: crashed: BUG: unable to handle kernel NULL pointer dereference in rhashtable_free_and_destroy run #8: crashed: INFO: task hung in rtnl_lock run #9: crashed: INFO: task hung in rtnl_lock testing current HEAD 0c88e405c97ed1828443b67891e6d4bb6e56cd4e testing commit 0c88e405c97ed1828443b67891e6d4bb6e56cd4e with gcc (GCC) 8.1.0 kernel signature: 7883d35e056904fd6e207ac23eb7dddc26ec8bd32232323431c9017bf768402b run #0: crashed: KASAN: wild-memory-access Write in rhashtable_free_and_destroy run #1: crashed: KASAN: wild-memory-access Write in rhashtable_free_and_destroy run #2: crashed: WARNING in rhashtable_free_and_destroy run #3: crashed: WARNING in rhashtable_free_and_destroy run #4: crashed: BUG: unable to handle kernel NULL pointer dereference in rhashtable_free_and_destroy run #5: crashed: general protection fault in rhashtable_free_and_destroy run #6: crashed: BUG: unable to handle kernel NULL pointer dereference in rhashtable_free_and_destroy run #7: crashed: general protection fault in get_work_pool run #8: crashed: INFO: task hung in rtnl_lock run #9: crashed: INFO: task hung in rtnl_lock revisions tested: 2, total time: 28m11.505357867s (build: 16m30.19281391s, test: 10m51.736879383s) the crash still happens on HEAD commit msg: Linux 4.19.160 crash: INFO: task hung in rtnl_lock Bluetooth: hci2: command 0x0406 tx timeout Bluetooth: hci4: command 0x0406 tx timeout Bluetooth: hci5: command 0x0406 tx timeout Bluetooth: hci3: command 0x0406 tx timeout Bluetooth: hci0: command 0x0406 tx timeout INFO: task kworker/0:0:5 blocked for more than 140 seconds. Not tainted 4.19.160-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:0 D25912 5 2 0x80000000 Workqueue: events linkwatch_event 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:1002 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 linkwatch_event+0x9/0x50 net/core/link_watch.c:236 process_one_work+0x7b9/0x15a0 kernel/workqueue.c:2155 worker_thread+0x85/0xb60 kernel/workqueue.c:2298 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 INFO: task kworker/1:0:19 blocked for more than 140 seconds. Not tainted 4.19.160-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:0 D24944 19 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:1002 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 addrconf_dad_work+0xa1/0xf70 net/ipv6/addrconf.c:3988 process_one_work+0x7b9/0x15a0 kernel/workqueue.c:2155 worker_thread+0x85/0xb60 kernel/workqueue.c:2298 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 INFO: task kworker/0:4:8321 blocked for more than 140 seconds. Not tainted 4.19.160-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:4 D26576 8321 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:1002 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 addrconf_dad_work+0xa1/0xf70 net/ipv6/addrconf.c:3988 process_one_work+0x7b9/0x15a0 kernel/workqueue.c:2155 worker_thread+0x85/0xb60 kernel/workqueue.c:2298 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 INFO: task syz-executor.3:8495 blocked for more than 140 seconds. Not tainted 4.19.160-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D23800 8495 1 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:1002 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 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+0x666/0xc50 net/netlink/af_netlink.c:1909 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:632 __sys_sendto+0x1f2/0x2e0 net/socket.c:1787 __do_sys_sendto net/socket.c:1799 [inline] __se_sys_sendto net/socket.c:1795 [inline] __x64_sys_sendto+0xdc/0x1a0 net/socket.c:1795 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4178d7 Code: 89 c8 48 c1 f9 3f 48 29 ca 48 8d 14 92 48 89 c3 48 29 d0 48 83 f8 05 72 af e9 11 01 00 00 48 8b 15 66 22 1a 01 48 8b 5a 08 48 <89> 1d 5b 22 1a 01 48 8b 1d 64 22 1a 01 48 89 5a 08 48 89 15 59 22 RSP: 002b:00007ffec9a95b10 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00000000016a4300 RCX: 00000000004178d7 RDX: 0000000000000020 RSI: 00000000016a4350 RDI: 0000000000000004 RBP: 0000000000000000 R08: 00007ffec9a95b20 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 00007ffec9a95b8c R13: 0000000000000010 R14: 00000000016a4350 R15: 0000000000000004 INFO: task syz-executor.0:8503 blocked for more than 140 seconds. Not tainted 4.19.160-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D23312 8503 1 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:1002 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 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+0x666/0xc50 net/netlink/af_netlink.c:1909 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:632 __sys_sendto+0x1f2/0x2e0 net/socket.c:1787 __do_sys_sendto net/socket.c:1799 [inline] __se_sys_sendto net/socket.c:1795 [inline] __x64_sys_sendto+0xdc/0x1a0 net/socket.c:1795 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4178d7 Code: 89 c8 48 c1 f9 3f 48 29 ca 48 8d 14 92 48 89 c3 48 29 d0 48 83 f8 05 72 af e9 11 01 00 00 48 8b 15 66 22 1a 01 48 8b 5a 08 48 <89> 1d 5b 22 1a 01 48 8b 1d 64 22 1a 01 48 89 5a 08 48 89 15 59 22 RSP: 002b:00007fff9f3dfa70 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00000000016a4300 RCX: 00000000004178d7 RDX: 0000000000000040 RSI: 00000000016a4350 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007fff9f3dfa80 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00000000016a4350 R15: 0000000000000003 INFO: task kworker/u4:7:9915 blocked for more than 140 seconds. Not tainted 4.19.160-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:7 D27264 9915 2 0x80000000 Workqueue: cfg80211 cfg80211_event_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:1002 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 cfg80211_event_work+0xd/0x30 net/wireless/core.c:304 process_one_work+0x7b9/0x15a0 kernel/workqueue.c:2155 worker_thread+0x85/0xb60 kernel/workqueue.c:2298 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 INFO: task kworker/0:5:9953 blocked for more than 140 seconds. Not tainted 4.19.160-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:5 D28200 9953 2 0x80000000 Workqueue: events cfg80211_destroy_iface_wk 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:1002 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 netdev_run_todo+0x3f2/0x690 net/core/dev.c:8992 rtnl_unlock+0x9/0x10 net/core/rtnetlink.c:117 cfg80211_destroy_iface_wk+0x1e/0x30 net/wireless/core.c:330 process_one_work+0x7b9/0x15a0 kernel/workqueue.c:2155 worker_thread+0x85/0xb60 kernel/workqueue.c:2298 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 INFO: task syz-executor.1:9990 blocked for more than 140 seconds. Not tainted 4.19.160-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D27704 9990 8500 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:1002 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 genl_lock net/netlink/genetlink.c:33 [inline] genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 netlink_rcv_skb+0x13e/0x3d0 net/netlink/af_netlink.c:2455 genl_rcv+0x23/0x40 net/netlink/genetlink.c:638 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x443/0x660 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x666/0xc50 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: 0033:0x45de59 Code: de 68 48 89 da 4c 8b 44 24 58 49 89 ca 48 89 c3 48 89 f0 48 8b 4c 24 40 e9 54 ff ff ff 48 8b 7c 24 60 e8 ba 3e 00 00 eb d9 48 <8d> 3c cb 48 89 c3 4c 89 c8 e8 a9 3e 00 00 49 8d 78 28 31 c0 e8 9e RSP: 002b:00007f6d71dabc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000002b9c0 RCX: 000000000045de59 RDX: 0000000000000000 RSI: 00000000200006c0 RDI: 0000000000000003 RBP: 00007f6d71dabca0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000b R13: 00007ffc9bf02adf R14: 00007f6d71dac9c0 R15: 000000000118bf2c INFO: task syz-executor.4:9994 blocked for more than 140 seconds. Not tainted 4.19.160-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D26360 9994 8497 0x80000004 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 __cancel_work_timer+0x396/0x430 kernel/workqueue.c:3001 cancel_work_sync+0xb/0x10 kernel/workqueue.c:3051 rhashtable_free_and_destroy+0x25/0x690 lib/rhashtable.c:1145 mesh_table_free net/mac80211/mesh_pathtbl.c:72 [inline] mesh_pathtbl_init+0xb4/0xe0 net/mac80211/mesh_pathtbl.c:798 ieee80211_mesh_init_sdata+0x183/0x3e0 net/mac80211/mesh.c:1461 ieee80211_setup_sdata+0xc5b/0xf20 net/mac80211/iface.c:1459 ieee80211_if_add+0x78f/0x16d0 net/mac80211/iface.c:1871 ieee80211_add_iface+0x7a/0xf0 net/mac80211/cfg.c:125 rdev_add_virtual_intf net/wireless/rdev-ops.h:45 [inline] nl80211_new_interface+0x438/0x1380 net/wireless/nl80211.c:3268 genl_family_rcv_msg+0x599/0x1000 net/netlink/genetlink.c:602 genl_rcv_msg+0xa7/0x140 net/netlink/genetlink.c:627 netlink_rcv_skb+0x13e/0x3d0 net/netlink/af_netlink.c:2455 genl_rcv+0x23/0x40 net/netlink/genetlink.c:638 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x443/0x660 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x666/0xc50 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: 0033:0x45de59 Code: de 68 48 89 da 4c 8b 44 24 58 49 89 ca 48 89 c3 48 89 f0 48 8b 4c 24 40 e9 54 ff ff ff 48 8b 7c 24 60 e8 ba 3e 00 00 eb d9 48 <8d> 3c cb 48 89 c3 4c 89 c8 e8 a9 3e 00 00 49 8d 78 28 31 c0 e8 9e RSP: 002b:00007fb848a9ac78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000002b9c0 RCX: 000000000045de59 RDX: 0000000000000000 RSI: 00000000200006c0 RDI: 0000000000000003 RBP: 00007fb848a9aca0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000b R13: 00007ffe742747bf R14: 00007fb848a9b9c0 R15: 000000000118bf2c INFO: task syz-executor.5:10005 blocked for more than 140 seconds. Not tainted 4.19.160-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28776 10005 8502 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:1002 [inline] __mutex_lock+0x4c3/0x1200 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 genl_lock net/netlink/genetlink.c:33 [inline] genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 netlink_rcv_skb+0x13e/0x3d0 net/netlink/af_netlink.c:2455 genl_rcv+0x23/0x40 net/netlink/genetlink.c:638 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x443/0x660 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x666/0xc50 net/netlink/af_netlink.c:1909 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:632 __sys_sendto+0x1f2/0x2e0 net/socket.c:1787 __do_sys_sendto net/socket.c:1799 [inline] __se_sys_sendto net/socket.c:1795 [inline] __x64_sys_sendto+0xdc/0x1a0 net/socket.c:1795 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4178d7 Code: 89 c8 48 c1 f9 3f 48 29 ca 48 8d 14 92 48 89 c3 48 29 d0 48 83 f8 05 72 af e9 11 01 00 00 48 8b 15 66 22 1a 01 48 8b 5a 08 48 <89> 1d 5b 22 1a 01 48 8b 1d 64 22 1a 01 48 89 5a 08 48 89 15 59 22 RSP: 002b:00007f537da86b40 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f537da86bf0 RCX: 00000000004178d7 RDX: 0000000000000020 RSI: 00007f537da86c40 RDI: 0000000000000005 RBP: 0000000000000000 R08: 00007f537da86b50 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 00007f537da86bb4 R13: 0000000000000010 R14: 00007f537da86c40 R15: 0000000000000005 Showing all locks held in the system: 3 locks held by kworker/0:0/5: #0: 000000005557da05 ((wq_completion)"events"){+.+.}, at: process_one_work+0x6e8/0x15a0 kernel/workqueue.c:2126 #1: 0000000030f78024 ((linkwatch_work).work){+.+.}, at: process_one_work+0x71b/0x15a0 kernel/workqueue.c:2130 #2: 00000000654dc4a1 (rtnl_mutex){+.+.}, at: rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 3 locks held by kworker/1:0/19: #0: 00000000b2500b07 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: process_one_work+0x6e8/0x15a0 kernel/workqueue.c:2126 #1: 000000002a31044d ((work_completion)(&(&ifa->dad_work)->work)){+.+.}, at: process_one_work+0x71b/0x15a0 kernel/workqueue.c:2130 #2: 00000000654dc4a1 (rtnl_mutex){+.+.}, at: rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 1 lock held by khungtaskd/1566: #0: 00000000ff41b63a (rcu_read_lock){....}, at: debug_show_all_locks+0x5b/0x27a kernel/locking/lockdep.c:4442 3 locks held by kworker/0:4/8321: #0: 00000000b2500b07 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: process_one_work+0x6e8/0x15a0 kernel/workqueue.c:2126 #1: 00000000e7d2ec00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}, at: process_one_work+0x71b/0x15a0 kernel/workqueue.c:2130 #2: 00000000654dc4a1 (rtnl_mutex){+.+.}, at: rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 1 lock held by syz-executor.3/8495: #0: 00000000654dc4a1 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 00000000654dc4a1 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x301/0x950 net/core/rtnetlink.c:4775 1 lock held by syz-executor.0/8503: #0: 00000000654dc4a1 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 00000000654dc4a1 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x301/0x950 net/core/rtnetlink.c:4775 3 locks held by kworker/1:4/9716: #0: 000000006b9cd3f5 ((wq_completion)"events_power_efficient"){+.+.}, at: process_one_work+0x6e8/0x15a0 kernel/workqueue.c:2126 #1: 00000000eb54052c ((reg_check_chans).work){+.+.}, at: process_one_work+0x71b/0x15a0 kernel/workqueue.c:2130 #2: 00000000654dc4a1 (rtnl_mutex){+.+.}, at: rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 3 locks held by kworker/u4:7/9915: #0: 00000000d85becc7 ((wq_completion)"cfg80211"){+.+.}, at: process_one_work+0x6e8/0x15a0 kernel/workqueue.c:2126 #1: 00000000787488f8 ((work_completion)(&rdev->event_work)){+.+.}, at: process_one_work+0x71b/0x15a0 kernel/workqueue.c:2130 #2: 00000000654dc4a1 (rtnl_mutex){+.+.}, at: rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 3 locks held by kworker/0:5/9953: #0: 000000005557da05 ((wq_completion)"events"){+.+.}, at: process_one_work+0x6e8/0x15a0 kernel/workqueue.c:2126 #1: 00000000aba6d66e ((work_completion)(&rdev->destroy_work)){+.+.}, at: process_one_work+0x71b/0x15a0 kernel/workqueue.c:2130 #2: 00000000654dc4a1 (rtnl_mutex){+.+.}, at: rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 2 locks held by syz-executor.1/9990: #0: 0000000038209579 (cb_lock){++++}, at: genl_rcv+0x14/0x40 net/netlink/genetlink.c:637 #1: 0000000069d9ed50 (genl_mutex){+.+.}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: 0000000069d9ed50 (genl_mutex){+.+.}, at: genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 3 locks held by syz-executor.4/9994: #0: 0000000038209579 (cb_lock){++++}, at: genl_rcv+0x14/0x40 net/netlink/genetlink.c:637 #1: 0000000069d9ed50 (genl_mutex){+.+.}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: 0000000069d9ed50 (genl_mutex){+.+.}, at: genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 #2: 00000000654dc4a1 (rtnl_mutex){+.+.}, at: rtnl_lock+0x12/0x20 net/core/rtnetlink.c:77 2 locks held by syz-executor.5/10005: #0: 0000000038209579 (cb_lock){++++}, at: genl_rcv+0x14/0x40 net/netlink/genetlink.c:637 #1: 0000000069d9ed50 (genl_mutex){+.+.}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: 0000000069d9ed50 (genl_mutex){+.+.}, at: genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 2 locks held by syz-executor.2/10007: #0: 0000000038209579 (cb_lock){++++}, at: genl_rcv+0x14/0x40 net/netlink/genetlink.c:637 #1: 0000000069d9ed50 (genl_mutex){+.+.}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: 0000000069d9ed50 (genl_mutex){+.+.}, at: genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:625 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1566 Comm: khungtaskd Not tainted 4.19.160-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/0x22a lib/dump_stack.c:118 nmi_cpu_backtrace.cold.0+0x3c/0x78 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0xf6/0x11a 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 skipped: idling at native_safe_halt+0x12/0x20 arch/x86/include/asm/irqflags.h:60