INFO: task hung in rtnl

Kernel	Title	Rank 🛈	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
linux-4.19	INFO: task hung in rtnl_newlink	1				1	1640d	1640d	0/1	auto-closed as invalid on 2021/07/01 14:20
INFO: task syz-executor:14503 blocked for more than 122 seconds.
      Not tainted 6.12.30-syzkaller-ge87018c5f9d0 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:0     pid:14503 tgid:14503 ppid:1      flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5929 [inline]
 __schedule+0x145b/0x1f10 kernel/sched/core.c:7755
 __schedule_loop kernel/sched/core.c:7836 [inline]
 schedule+0xc6/0x240 kernel/sched/core.c:7851
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7908
 __mutex_lock_common kernel/locking/mutex.c:692 [inline]
 __mutex_lock+0x836/0x1b60 kernel/locking/mutex.c:786
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1117
 mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:270
 rtnl_lock net/core/rtnetlink.c:79 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3752 [inline]
 rtnl_newlink+0xa5c/0x2130 net/core/rtnetlink.c:3775
 rtnetlink_rcv_msg+0x882/0xa00 net/core/rtnetlink.c:6678
 netlink_rcv_skb+0x22b/0x4a0 net/netlink/af_netlink.c:2537
 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6696
 netlink_unicast_kernel net/netlink/af_netlink.c:1316 [inline]
 netlink_unicast+0x8c9/0xa60 net/netlink/af_netlink.c:1342
 netlink_sendmsg+0x7f0/0xaf0 net/netlink/af_netlink.c:1886
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 __sys_sendto+0x66a/0x6f0 net/socket.c:2217
 __do_sys_sendto net/socket.c:2229 [inline]
 __se_sys_sendto net/socket.c:2225 [inline]
 __x64_sys_sendto+0xe9/0x100 net/socket.c:2225
 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f8f34b90763
RSP: 002b:00007ffe40f55fc8 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f8f358e4620 RCX: 00007f8f34b90763
RDX: 000000000000003c RSI: 00007f8f358e4670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffe40f55fe4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f8f358e4670 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:14507 blocked for more than 123 seconds.
      Not tainted 6.12.30-syzkaller-ge87018c5f9d0 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:0     pid:14507 tgid:14507 ppid:1      flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5929 [inline]
 __schedule+0x145b/0x1f10 kernel/sched/core.c:7755
 __schedule_loop kernel/sched/core.c:7836 [inline]
 schedule+0xc6/0x240 kernel/sched/core.c:7851
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7908
 __mutex_lock_common kernel/locking/mutex.c:692 [inline]
 __mutex_lock+0x836/0x1b60 kernel/locking/mutex.c:786
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1117
 mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:270
 rtnl_lock net/core/rtnetlink.c:79 [inline]
 rtnetlink_rcv_msg+0x75f/0xa00 net/core/rtnetlink.c:6675
 netlink_rcv_skb+0x22b/0x4a0 net/netlink/af_netlink.c:2537
 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6696
 netlink_unicast_kernel net/netlink/af_netlink.c:1316 [inline]
 netlink_unicast+0x8c9/0xa60 net/netlink/af_netlink.c:1342
 netlink_sendmsg+0x7f0/0xaf0 net/netlink/af_netlink.c:1886
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 __sys_sendto+0x66a/0x6f0 net/socket.c:2217
 __do_sys_sendto net/socket.c:2229 [inline]
 __se_sys_sendto net/socket.c:2225 [inline]
 __x64_sys_sendto+0xe9/0x100 net/socket.c:2225
 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f52a4d90763
RSP: 002b:00007ffd6efe4bc8 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f52a5ae4620 RCX: 00007f52a4d90763
RDX: 000000000000003c RSI: 00007f52a5ae4670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffd6efe4be4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f52a5ae4670 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:14509 blocked for more than 124 seconds.
      Not tainted 6.12.30-syzkaller-ge87018c5f9d0 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:0     pid:14509 tgid:14509 ppid:1      flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5929 [inline]
 __schedule+0x145b/0x1f10 kernel/sched/core.c:7755
 __schedule_loop kernel/sched/core.c:7836 [inline]
 schedule+0xc6/0x240 kernel/sched/core.c:7851
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7908
 __mutex_lock_common kernel/locking/mutex.c:692 [inline]
 __mutex_lock+0x836/0x1b60 kernel/locking/mutex.c:786
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1117
 mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:270
 rtnl_lock net/core/rtnetlink.c:79 [inline]
 rtnetlink_rcv_msg+0x75f/0xa00 net/core/rtnetlink.c:6675
 netlink_rcv_skb+0x22b/0x4a0 net/netlink/af_netlink.c:2537
 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6696
 netlink_unicast_kernel net/netlink/af_netlink.c:1316 [inline]
 netlink_unicast+0x8c9/0xa60 net/netlink/af_netlink.c:1342
 netlink_sendmsg+0x7f0/0xaf0 net/netlink/af_netlink.c:1886
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 __sys_sendto+0x66a/0x6f0 net/socket.c:2217
 __do_sys_sendto net/socket.c:2229 [inline]
 __se_sys_sendto net/socket.c:2225 [inline]
 __x64_sys_sendto+0xe9/0x100 net/socket.c:2225
 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f7ddcb90763
RSP: 002b:00007ffdda539b98 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f7ddd8e4620 RCX: 00007f7ddcb90763
RDX: 000000000000003c RSI: 00007f7ddd8e4670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffdda539bb4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f7ddd8e4670 R15: 0000000000000000
 </TASK>
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted 6.12.30-syzkaller-ge87018c5f9d0 #0 5b8259740197b16b9e7f8b82a160421e9e39f8e6
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:94
 dump_stack_lvl+0x10c/0x190 lib/dump_stack.c:120
 dump_stack+0x19/0x20 lib/dump_stack.c:129
 nmi_cpu_backtrace+0x2bf/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:229 [inline]
 watchdog+0xd8f/0xed0 kernel/hung_task.c:385
 kthread+0x2c7/0x370 kernel/kthread.c:389
 ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 20 Comm: rcuop/0 Not tainted 6.12.30-syzkaller-ge87018c5f9d0 #0 5b8259740197b16b9e7f8b82a160421e9e39f8e6
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__find_rr_leaf+0x95/0x790 net/ipv6/route.c:829
Code: 00 10 b8 e0 84 48 8d 84 24 80 00 00 00 48 c1 e8 03 42 c7 04 28 f1 f1 f1 f1 42 c7 44 28 09 f3 f3 f3 f3 66 42 c7 44 28 0d f3 f3 <48> 89 44 24 20 42 c6 44 28 0f f3 e8 ab ea a4 fc 4c 89 64 24 70 4d
RSP: 0018:ffffc90000006d00 EFLAGS: 00000a02
RAX: 1ffff92000000db0 RBX: ffffc900000070f0 RCX: ffffc900000070f0
RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff8881303b7c00
RBP: ffffc90000006e58 R08: ffffc90000006f58 R09: 000000000000000d
R10: ffffc900000070f0 R11: fffff52000000e22 R12: 0000000000000000
R13: dffffc0000000000 R14: ffff8881303b7c00 R15: ffffc90000006f58
FS:  0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055868a3abb98 CR3: 000000010b7c4000 CR4: 00000000003526b0
Call Trace:
 <IRQ>
 find_rr_leaf net/ipv6/route.c:890 [inline]
 rt6_select net/ipv6/route.c:934 [inline]
 fib6_table_lookup+0x2c5/0x9b0 net/ipv6/route.c:2230
 ip6_pol_route+0x167/0x12c0 net/ipv6/route.c:2266
 ip6_pol_route_input+0x5a/0x80 net/ipv6/route.c:2323
 pol_lookup_func include/net/ip6_fib.h:626 [inline]
 fib6_rule_lookup+0x4cc/0x6b0 net/ipv6/fib6_rules.c:117
 ip6_route_input_lookup net/ipv6/route.c:2335 [inline]
 ip6_route_input+0x59f/0x8d0 net/ipv6/route.c:2631
 ip6_rcv_finish_core net/ipv6/ip6_input.c:66 [inline]
 ip6_rcv_finish+0x15a/0x3c0 net/ipv6/ip6_input.c:77
 NF_HOOK include/linux/netfilter.h:317 [inline]
 ipv6_rcv+0xed/0x220 net/ipv6/ip6_input.c:309
 __netif_receive_skb_one_core net/core/dev.c:5757 [inline]
 __netif_receive_skb net/core/dev.c:5870 [inline]
 netif_receive_skb_internal net/core/dev.c:5956 [inline]
 netif_receive_skb+0x147/0x7b0 net/core/dev.c:6015
 br_netif_receive_skb net/bridge/br_input.c:30 [inline]
 NF_HOOK include/linux/netfilter.h:317 [inline]
 br_pass_frame_up+0x126/0x1c0 net/bridge/br_input.c:70
 br_handle_frame_finish+0x12d9/0x1720 net/bridge/br_input.c:221
 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+0xf4b/0x3940 net/core/dev.c:5651
 __netif_receive_skb_one_core net/core/dev.c:5755 [inline]
 __netif_receive_skb net/core/dev.c:5870 [inline]
 process_backlog+0x3e5/0xae0 net/core/dev.c:6202
 __napi_poll+0xd3/0x610 net/core/dev.c:6853
 napi_poll net/core/dev.c:6922 [inline]
 net_rx_action+0x584/0xce0 net/core/dev.c:7044
 handle_softirqs+0x1ae/0x630 kernel/softirq.c:603
 __do_softirq+0xf/0x16 kernel/softirq.c:641
 do_softirq+0xa6/0x100 kernel/softirq.c:485
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x74/0x80 kernel/softirq.c:412
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 rcu_do_batch+0x5c6/0xd20 kernel/rcu/tree.c:2586
 nocb_cb_wait kernel/rcu/tree_nocb.h:923 [inline]
 rcu_nocb_cb_kthread+0x4dc/0xac0 kernel/rcu/tree_nocb.h:957
 kthread+0x2c7/0x370 kernel/kthread.c:389
 ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
net_ratelimit: 93071 callbacks suppressed
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:46:46:88:cf:19:5b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, 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:1b, 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:1b, 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:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)