INFO: task kworker/1:1:29 blocked for more than 143 seconds. Not tainted 5.9.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:1 state:D stack:27536 pid: 29 ppid: 2 flags:0x00004000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0xec9/0x2280 kernel/sched/core.c:4527 schedule+0xd0/0x2a0 kernel/sched/core.c:4602 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4661 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10e0 kernel/locking/mutex.c:1103 addrconf_dad_work+0xa3/0x1280 net/ipv6/addrconf.c:4027 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 INFO: task kworker/0:0:6867 blocked for more than 143 seconds. Not tainted 5.9.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:0 state:D stack:28160 pid: 6867 ppid: 2 flags:0x00004000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0xec9/0x2280 kernel/sched/core.c:4527 schedule+0xd0/0x2a0 kernel/sched/core.c:4602 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4661 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10e0 kernel/locking/mutex.c:1103 addrconf_dad_work+0xa3/0x1280 net/ipv6/addrconf.c:4027 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 INFO: task syz-executor019:6918 blocked for more than 143 seconds. Not tainted 5.9.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor019 state:D stack:25816 pid: 6918 ppid: 6875 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0xec9/0x2280 kernel/sched/core.c:4527 schedule+0xd0/0x2a0 kernel/sched/core.c:4602 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4661 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10e0 kernel/locking/mutex.c:1103 tcf_action_init_1+0x747/0x990 net/sched/act_api.c:966 tcf_action_init+0x265/0x4b0 net/sched/act_api.c:1040 tcf_action_add+0xd9/0x360 net/sched/act_api.c:1453 tc_ctl_action+0x33a/0x439 net/sched/act_api.c:1506 rtnetlink_rcv_msg+0x44e/0xad0 net/core/rtnetlink.c:5563 netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2470 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:671 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2353 ___sys_sendmsg+0xf3/0x170 net/socket.c:2407 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2440 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x448189 Code: Bad RIP value. RSP: 002b:00007f64bac32d98 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00000000006e39e8 RCX: 0000000000448189 RDX: 0000000000000000 RSI: 0000000020002980 RDI: 0000000000000003 RBP: 00000000006e39e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006e39ec R13: 0001008400000000 R14: 0000000000000000 R15: 053b003000000098 Showing all locks held in the system: 3 locks held by kworker/1:1/29: #0: ffff888214dda538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888214dda538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888214dda538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888214dda538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888214dda538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888214dda538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240 #1: ffffc90000e37da8 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244 #2: ffffffff8b14d548 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xa3/0x1280 net/ipv6/addrconf.c:4027 1 lock held by khungtaskd/1172: #0: ffffffff8a067f00 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5852 1 lock held by in:imklog/6555: #0: ffff888097ae9d70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:930 3 locks held by kworker/0:0/6867: #0: ffff888214dda538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888214dda538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888214dda538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888214dda538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff888214dda538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff888214dda538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240 #1: ffffc900051efda8 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244 #2: ffffffff8b14d548 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xa3/0x1280 net/ipv6/addrconf.c:4027 1 lock held by syz-executor019/6918: #0: ffffffff8b14d548 (rtnl_mutex){+.+.}-{3:3}, at: tcf_action_init_1+0x747/0x990 net/sched/act_api.c:966 2 locks held by syz-executor019/6920: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1172 Comm: khungtaskd Not tainted 5.9.0-rc6-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+0x198/0x1fd lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b3/0x223 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xd7d/0x1000 kernel/hung_task.c:295 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 6920 Comm: syz-executor019 Not tainted 5.9.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:rcu_lockdep_current_cpu_online kernel/rcu/tree.c:1163 [inline] RIP: 0010:rcu_lockdep_current_cpu_online+0xd4/0x120 kernel/rcu/tree.c:1150 Code: 5b 20 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 49 48 8b 45 70 48 85 c3 0f 95 c0 65 ff 0d 1c 30 9f 7e <74> 03 5b 5d c3 e8 d1 aa 9d ff eb f6 48 89 ee 48 c7 c7 40 ef 06 8a RSP: 0018:ffffc90005526d68 EFLAGS: 00000282 RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffffff815c000f RDX: 1ffffffff140df56 RSI: 0000000000000002 RDI: ffffffff8a06fab0 RBP: ffffffff8a06fa40 R08: 0000000000000000 R09: ffffffff8b59654f R10: fffffbfff16b2ca9 R11: 0000000000000000 R12: 0000000000000001 R13: ffff88809e939e68 R14: ffffffff868a961e R15: ffff88809e939e00 FS: 00007f64bac12700(0000) GS:ffff8880ae400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000561d9be49d10 CR3: 00000000a8d86000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_lock_held_common kernel/rcu/update.c:123 [inline] rcu_read_lock_held_common kernel/rcu/update.c:113 [inline] rcu_read_lock_sched_held+0x25/0xb0 kernel/rcu/update.c:134 trace_lock_release include/trace/events/lock.h:58 [inline] lock_release+0x6a1/0x8f0 kernel/locking/lockdep.c:5040 __mutex_unlock_slowpath+0x81/0x610 kernel/locking/mutex.c:1228 tcf_idr_check_alloc+0x29e/0x3b0 net/sched/act_api.c:506 tcf_connmark_init+0x2de/0x910 net/sched/act_connmark.c:124 tcf_action_init_1+0x63f/0x990 net/sched/act_api.c:988 tcf_action_init+0x265/0x4b0 net/sched/act_api.c:1040 tcf_action_add+0xd9/0x360 net/sched/act_api.c:1453 tc_ctl_action+0x33a/0x439 net/sched/act_api.c:1506 rtnetlink_rcv_msg+0x44e/0xad0 net/core/rtnetlink.c:5563 netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2470 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:671 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2353 ___sys_sendmsg+0xf3/0x170 net/socket.c:2407 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2440 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x448189 Code: e8 5c 08 03 00 48 83 c4 18 c3 0f 1f 80 00 00 00 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 0f 83 eb 05 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f64bac11d98 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00000000006e39f8 RCX: 0000000000448189 RDX: 0000000000000000 RSI: 0000000020002980 RDI: 0000000000000004 RBP: 00000000006e39f0 R08: 000000000000000d R09: 0000000000000000 R10: 0000000000000050 R11: 0000000000000246 R12: 00000000006e39fc R13: 0001008400000000 R14: 0000000000000000 R15: 053b003000000098