INFO: task hung in rtnl_dumpit (3)

Status: premoderation: reported on 2026/11/04 16:55
Reported-by: syzbot+e3bb0dd9034fbc9e0ebd@syzkaller.appspotmail.com
First crash: 23h33m, last: 23h33m
▶ ▼ Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-6-12 INFO: task hung in rtnl_dumpit (2) 1 1 163d 163d 0/1 auto-obsoleted due to no activity on 2026/08/24 06:07
upstream INFO: task hung in rtnl_dumpit (2) prio:high net 1 128 38d 611d 0/29 closed as invalid on 2026/10/06 01:41
android-6-12 INFO: task hung in rtnl_dumpit 1 2 426d 482d 0/1 auto-obsoleted due to no activity on 2025/12/03 19:43

Sample crash report:
INFO: task dhcpcd:148 blocked for more than 122 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:dhcpcd          state:D stack:0     pid:148   tgid:148   ppid:147    flags:0x00000000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6109 [inline]
 __schedule+0x16e0/0x2380 kernel/sched/core.c:7956
 __schedule_loop kernel/sched/core.c:8031 [inline]
 schedule+0xc1/0x170 kernel/sched/core.c:8046
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8103
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x95d/0x1d10 kernel/locking/mutex.c:807
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1137
 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
 rtnl_lock net/core/rtnetlink.c:79 [inline]
 rtnl_dumpit+0xa1/0x240 net/core/rtnetlink.c:6546
 netlink_dump+0x795/0x10d0 net/netlink/af_netlink.c:2329
 netlink_recvmsg+0x693/0xe60 net/netlink/af_netlink.c:1977
 sock_recvmsg_nosec net/socket.c:1035 [inline]
 sock_recvmsg+0x188/0x1e0 net/socket.c:1057
 ____sys_recvmsg+0x1e7/0x4a0 net/socket.c:2804
 ___sys_recvmsg+0x214/0x590 net/socket.c:2846
 __sys_recvmsg net/socket.c:2879 [inline]
 __do_sys_recvmsg net/socket.c:2885 [inline]
 __se_sys_recvmsg net/socket.c:2882 [inline]
 __x64_sys_recvmsg+0x1bb/0x2a0 net/socket.c:2882
 x64_sys_call+0xdb5/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:48
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f1db1435407
RSP: 002b:00007ffd6dad8350 EFLAGS: 00000202
 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 00007f1db13ab740 RCX: 00007f1db1435407
RDX: 0000000000000000 RSI: 00007ffd6dad83e0 RDI: 0000000000000012
RBP: 00007ffd6dad83c4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000b44
R13: 00007ffd6dad83d0 R14: 00007ffd6dad84c0 R15: 0000000000000000
 </TASK>
INFO: task kworker/u8:3:308 blocked for more than 124 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:3    state:D stack:0     pid:308   tgid:308   ppid:2      flags:0x00004000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6109 [inline]
 __schedule+0x16e0/0x2380 kernel/sched/core.c:7956
 __schedule_loop kernel/sched/core.c:8031 [inline]
 schedule+0xc1/0x170 kernel/sched/core.c:8046
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8103
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x95d/0x1d10 kernel/locking/mutex.c:807
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1137
 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
 rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79
 addrconf_dad_work+0xc8/0x1550 net/ipv6/addrconf.c:4237
 process_one_work kernel/workqueue.c:3273 [inline]
 process_scheduled_works+0x7f7/0x1060 kernel/workqueue.c:3354
 worker_thread+0xc99/0x13f0 kernel/workqueue.c:3435
 kthread+0x2c7/0x360 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>
INFO: task kworker/u8:4:309 blocked for more than 125 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:4    state:D stack:0     pid:309   tgid:309   ppid:2      flags:0x00004000
Workqueue: events_unbound linkwatch_event
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6109 [inline]
 __schedule+0x16e0/0x2380 kernel/sched/core.c:7956
 __schedule_loop kernel/sched/core.c:8031 [inline]
 schedule+0xc1/0x170 kernel/sched/core.c:8046
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8103
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x95d/0x1d10 kernel/locking/mutex.c:807
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1137
 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
 rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79
 linkwatch_event+0x12/0x60 net/core/link_watch.c:285
 process_one_work kernel/workqueue.c:3273 [inline]
 process_scheduled_works+0x7f7/0x1060 kernel/workqueue.c:3354
 worker_thread+0xc99/0x13f0 kernel/workqueue.c:3435
 kthread+0x2c7/0x360 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>
INFO: task syz-executor:689 blocked for more than 126 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:0     pid:689   tgid:689   ppid:1      flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6109 [inline]
 __schedule+0x16e0/0x2380 kernel/sched/core.c:7956
 __schedule_loop kernel/sched/core.c:8031 [inline]
 schedule+0xc1/0x170 kernel/sched/core.c:8046
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8103
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x95d/0x1d10 kernel/locking/mutex.c:807
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1137
 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
 rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79
 ip_tunnel_init_net+0x2ff/0x880 net/ipv4/ip_tunnel.c:1145
 erspan_init_net+0x2d/0x40 net/ipv4/ip_gre.c:1773
 ops_init+0x302/0x5d0 net/core/net_namespace.c:139
 setup_net+0x227/0x9b0 net/core/net_namespace.c:356
 copy_net_ns+0x4fc/0xa20 net/core/net_namespace.c:510
 create_new_namespaces+0x390/0x6f0 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228
 ksys_unshare+0x4f9/0x920 kernel/fork.c:3391
 __do_sys_unshare kernel/fork.c:3477 [inline]
 __se_sys_unshare kernel/fork.c:3475 [inline]
 __x64_sys_unshare+0x3c/0x50 kernel/fork.c:3475
 x64_sys_call+0x2998/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:273
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fefbb7a0de7
RSP: 002b:00007fff1de715b8 EFLAGS: 00000206 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007fefbba25f40 RCX: 00007fefbb7a0de7
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007fefbba267b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000008
R13: 0000000000000003 R14: 00007fff1de717f8 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:691 blocked for more than 127 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:0     pid:691   tgid:691   ppid:1      flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6109 [inline]
 __schedule+0x16e0/0x2380 kernel/sched/core.c:7956
 __schedule_loop kernel/sched/core.c:8031 [inline]
 schedule+0xc1/0x170 kernel/sched/core.c:8046
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8103
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x95d/0x1d10 kernel/locking/mutex.c:807
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1137
 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
 rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79
 ip_tunnel_init_net+0x2ff/0x880 net/ipv4/ip_tunnel.c:1145
 ipgre_init_net+0x28/0x30 net/ipv4/ip_gre.c:1070
 ops_init+0x302/0x5d0 net/core/net_namespace.c:139
 setup_net+0x227/0x9b0 net/core/net_namespace.c:356
 copy_net_ns+0x4fc/0xa20 net/core/net_namespace.c:510
 create_new_namespaces+0x390/0x6f0 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228
 ksys_unshare+0x4f9/0x920 kernel/fork.c:3391
 __do_sys_unshare kernel/fork.c:3477 [inline]
 __se_sys_unshare kernel/fork.c:3475 [inline]
 __x64_sys_unshare+0x3c/0x50 kernel/fork.c:3475
 x64_sys_call+0x2998/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:273
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f388f7a0de7
RSP: 002b:00007ffdcc864258 EFLAGS: 00000206 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f388fa25f40 RCX: 00007f388f7a0de7
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007f388fa267b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000008
R13: 0000000000000003 R14: 00007ffdcc864498 R15: 0000000000000000
 </TASK>
INFO: task syz.3.144:703 blocked for more than 127 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.144       state:D stack:0     pid:703   tgid:702   ppid:294    flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6109 [inline]
 __schedule+0x16e0/0x2380 kernel/sched/core.c:7956
 __schedule_loop kernel/sched/core.c:8031 [inline]
 schedule+0xc1/0x170 kernel/sched/core.c:8046
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8103
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x95d/0x1d10 kernel/locking/mutex.c:807
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1137
 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
 rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79
 tun_detach drivers/net/tun.c:698 [inline]
 tun_chr_close+0x41/0x150 drivers/net/tun.c:3523
 __fput+0x20b/0xa30 fs/file_table.c:447
 ____fput+0x20/0x30 fs/file_table.c:475
 task_work_run+0x1e8/0x260 kernel/task_work.c:246
 get_signal+0x12b3/0x1490 kernel/signal.c:2715
 arch_do_signal_or_restart+0xbc/0x700 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x57/0xb0 kernel/entry/common.c:218
 do_syscall_64+0x63/0xf0 arch/x86/entry/common.c:84
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fad8a39fb19
RSP: 002b:00007fad8b27f028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007fad8a625fa0 RCX: 00007fad8a39fb19
RDX: 0000200000000c80 RSI: 00000000400454ca RDI: 0000000000000003
RBP: 00007fad8a437b70 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fad8a626038 R14: 00007fad8a625fa0 R15: 00007ffcaba1a5a8
 </TASK>
INFO: task syz.0.146:715 blocked for more than 128 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.146       state:D stack:0     pid:715   tgid:714   ppid:295    flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6109 [inline]
 __schedule+0x16e0/0x2380 kernel/sched/core.c:7956
 __schedule_loop kernel/sched/core.c:8031 [inline]
 schedule+0xc1/0x170 kernel/sched/core.c:8046
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8103
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x95d/0x1d10 kernel/locking/mutex.c:807
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1137
 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
 rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79
 tun_detach drivers/net/tun.c:698 [inline]
 tun_chr_close+0x41/0x150 drivers/net/tun.c:3523
 __fput+0x20b/0xa30 fs/file_table.c:447
 ____fput+0x20/0x30 fs/file_table.c:475
 task_work_run+0x1e8/0x260 kernel/task_work.c:246
 exit_task_work include/linux/task_work.h:43 [inline]
 do_exit+0xa46/0x2850 kernel/exit.c:961
 do_group_exit+0x21f/0x2f0 kernel/exit.c:1104
 get_signal+0x134c/0x1490 kernel/signal.c:2942
 arch_do_signal_or_restart+0xbc/0x700 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x57/0xb0 kernel/entry/common.c:218
 do_syscall_64+0x63/0xf0 arch/x86/entry/common.c:84
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f81d0f9fb19
RSP: 002b:00007f81d1f00028 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: 0000000000000012 RBX: 00007f81d1225fa0 RCX: 00007f81d0f9fb19
RDX: 0000000000000012 RSI: 00002000000006c0 RDI: 0000000000000003
RBP: 00007f81d1037b70 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f81d1226038 R14: 00007f81d1225fa0 R15: 00007fffc4ea2758
 </TASK>
INFO: task syz-executor:722 blocked for more than 130 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:0     pid:722   tgid:722   ppid:1      flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6109 [inline]
 __schedule+0x16e0/0x2380 kernel/sched/core.c:7956
 __schedule_loop kernel/sched/core.c:8031 [inline]
 schedule+0xc1/0x170 kernel/sched/core.c:8046
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8103
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x95d/0x1d10 kernel/locking/mutex.c:807
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1137
 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
 rtnl_lock net/core/rtnetlink.c:79 [inline]
 rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6684
 netlink_rcv_skb+0x24a/0x4e0 net/netlink/af_netlink.c:2554
 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6705
 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
 netlink_unicast+0x8bf/0xa70 net/netlink/af_netlink.c:1340
 netlink_sendmsg+0x7d1/0xad0 net/netlink/af_netlink.c:1895
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg net/socket.c:727 [inline]
 __sys_sendto+0x663/0x6e0 net/socket.c:2198
 __do_sys_sendto net/socket.c:2205 [inline]
 __se_sys_sendto net/socket.c:2201 [inline]
 __x64_sys_sendto+0xe9/0x100 net/socket.c:2201
 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fe6e335ac97
RSP: 002b:00007ffcf9eeec10 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 000055557b6d9500 RCX: 00007fe6e335ac97
RDX: 000000000000002c RSI: 00007fe6e4154670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffcf9eeec74 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fe6e4154670 R15: 0000000000000000
 </TASK>
INFO: task syz-executor:724 blocked for more than 131 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:0     pid:724   tgid:724   ppid:1      flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6109 [inline]
 __schedule+0x16e0/0x2380 kernel/sched/core.c:7956
 __schedule_loop kernel/sched/core.c:8031 [inline]
 schedule+0xc1/0x170 kernel/sched/core.c:8046
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8103
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x95d/0x1d10 kernel/locking/mutex.c:807
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1137
 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
 rtnl_lock net/core/rtnetlink.c:79 [inline]
 rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6684
 netlink_rcv_skb+0x24a/0x4e0 net/netlink/af_netlink.c:2554
 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6705
 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
 netlink_unicast+0x8bf/0xa70 net/netlink/af_netlink.c:1340
 netlink_sendmsg+0x7d1/0xad0 net/netlink/af_netlink.c:1895
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg net/socket.c:727 [inline]
 __sys_sendto+0x663/0x6e0 net/socket.c:2198
 __do_sys_sendto net/socket.c:2205 [inline]
 __se_sys_sendto net/socket.c:2201 [inline]
 __x64_sys_sendto+0xe9/0x100 net/socket.c:2201
 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fc63555ac97
RSP: 002b:00007ffc93d5e920 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000555566411500 RCX: 00007fc63555ac97
RDX: 0000000000000028 RSI: 00007fc636354670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffc93d5e984 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fc636354670 R15: 0000000000000000
 </TASK>
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 6d6f333215c564de92c741644a4b57c848379815
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:94
 dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120
 dump_stack+0x19/0x20 lib/dump_stack.c:129
 nmi_cpu_backtrace+0x2ba/0x2d0 lib/nmi_backtrace.c:114
 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:63
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41
 cpumask_backtrace+0x1f/0x30 lib/nmi_backtrace.c:127
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline]
 watchdog+0xe45/0xf90 kernel/hung_task.c:423
 kthread+0x2c7/0x360 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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 20 Comm: rcuop/0 Not tainted syzkaller #0 6d6f333215c564de92c741644a4b57c848379815
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
RIP: 0010:arch_atomic_try_cmpxchg arch/x86/include/asm/atomic.h:107 [inline]
RIP: 0010:raw_atomic_try_cmpxchg_acquire include/linux/atomic/atomic-arch-fallback.h:2170 [inline]
RIP: 0010:atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1302 [inline]
RIP: 0010:queued_spin_lock include/asm-generic/qspinlock.h:111 [inline]
RIP: 0010:do_raw_spin_lock include/linux/spinlock.h:188 [inline]
RIP: 0010:__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline]
RIP: 0010:_raw_spin_lock_irqsave+0xc5/0x160 kernel/locking/spinlock.c:162
Code: 7a 43 c6 44 25 04 04 c7 44 24 20 00 00 00 00 be 04 00 00 00 e8 2c 35 36 fc 4c 89 ff be 04 00 00 00 e8 1f 35 36 fc 8b 44 24 20 <b9> 01 00 00 00 f0 0f b1 0b 75 47 43 c6 44 25 04 f8 48 c7 04 24 0e
RSP: 0018:ffffc9000022fee0 EFLAGS: 00000097
RAX: 0000000000000000 RBX: ffff8881f6d51584 RCX: ffffffff85ace501
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc9000022ff00
RBP: ffffc9000022ff90 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000045fe0 R12: dffffc0000000000
R13: 1ffff92000045fdc R14: 0000000000000a02 R15: ffffc9000022ff00
FS:  0000000000000000(0000) GS:ffff8881f6d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f70a7861491 CR3: 000000010d7d0000 CR4: 00000000003526b0
Call Trace:
 <IRQ>
 backlog_lock_irq_save net/core/dev.c:234 [inline]
 enqueue_to_backlog+0x153/0xb80 net/core/dev.c:5004
 netif_rx_internal+0xab/0x330 net/core/dev.c:5325
 __netif_rx+0x24/0x230 net/core/dev.c:5345
 veth_forward_skb drivers/net/veth.c:324 [inline]
 veth_xmit+0x420/0xb30 drivers/net/veth.c:378
 __netdev_start_xmit include/linux/netdevice.h:5008 [inline]
 netdev_start_xmit include/linux/netdevice.h:5017 [inline]
 xmit_one net/core/dev.c:3693 [inline]
 dev_hard_start_xmit+0x230/0x730 net/core/dev.c:3709
 __dev_queue_xmit+0x1969/0x3780 net/core/dev.c:4549
 dev_queue_xmit include/linux/netdevice.h:3141 [inline]
 br_dev_queue_push_xmit+0x571/0x710 net/bridge/br_forward.c:53
 NF_HOOK include/linux/netfilter.h:317 [inline]
 br_forward_finish net/bridge/br_forward.c:66 [inline]
 NF_HOOK include/linux/netfilter.h:317 [inline]
 __br_forward+0x24f/0x390 net/bridge/br_forward.c:115
 deliver_clone net/bridge/br_forward.c:131 [inline]
 maybe_deliver net/bridge/br_forward.c:191 [inline]
 br_flood+0x500/0x720 net/bridge/br_forward.c:237
 br_handle_frame_finish+0x1157/0x1620 net/bridge/br_input.c:215
 nf_hook_bridge_pre net/bridge/br_input.c:301 [inline]
 br_handle_frame+0x5a5/0xba0 net/bridge/br_input.c:424
 __netif_receive_skb_core+0xfc4/0x3a70 net/core/dev.c:5695
 __netif_receive_skb_one_core net/core/dev.c:5799 [inline]
 __netif_receive_skb net/core/dev.c:5914 [inline]
 process_backlog+0x40b/0xaf0 net/core/dev.c:6250
 __napi_poll+0xcd/0x600 net/core/dev.c:6901
 napi_poll net/core/dev.c:6970 [inline]
 net_rx_action+0x5dc/0xd70 net/core/dev.c:7092
 handle_softirqs+0x1b0/0x5b0 kernel/softirq.c:684
 __do_softirq+0xf/0x16 kernel/softirq.c:722
 do_softirq+0xb8/0x110 kernel/softirq.c:566
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x74/0x80 kernel/softirq.c:493
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 rcu_do_batch+0x590/0xcb0 kernel/rcu/tree.c:2594
 nocb_cb_wait kernel/rcu/tree_nocb.h:923 [inline]
 rcu_nocb_cb_kthread+0x533/0xb60 kernel/rcu/tree_nocb.h:957
 kthread+0x2c7/0x360 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>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/11/04 16:54 android16-6.12 a02a58da719e 73438ed0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_dumpit
* Struck through repros no longer work on HEAD.