INFO: task hung in nfsd_nl_threads_get_doit

Status: upstream: reported C repro on 2024/06/24 13:18
Subsystems: nfs
Labels: prio:low
[Documentation on labels]
Reported-by: syzbot+c0831b61d6ade1e2d098@syzkaller.appspotmail.com
First crash: 804d, last: 4h38m
▶ ▼ ✨ AI Patch Versions (1)
Version Stage Reported Report Link Job
1 moderation 2026/08/07 18:45 Discussion baf7f685-d9f6-4911-b692-3b89801723c0
▶ ▼ ✨ AI Jobs (5)
ID Workflow Result Correct Bug Created Started Finished Revision
baf7f685 patching ❓ INFO: task hung in nfsd_nl_threads_get_doit 2026/08/07 14:13 2026/08/07 14:13 2026/08/07 18:45 e4ef95d6
ec7ec28b repro-c Reproduced: ✅
❓ INFO: task hung in nfsd_nl_threads_get_doit 2026/08/06 14:12 2026/08/06 14:12 2026/08/06 17:19 c38879ea
a313f684 assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ ❓ INFO: task hung in nfsd_nl_threads_get_doit 2026/05/31 07:34 2026/05/31 07:34 2026/05/31 08:28 6b4a8443
7eba70e2 assessment-security 💥 INFO: task hung in nfsd_nl_threads_get_doit 2026/05/14 14:43 2026/05/14 14:43 2026/05/14 14:44 6ccb967e
1a74faa4 repro ❓ INFO: task hung in nfsd_nl_threads_get_doit 2026/03/06 22:15 2026/03/06 22:15 2026/03/06 22:25 31e9c887
▶ ▼ Discussions (3)
Title Replies (including bot) Last reply
[syzbot] [nfs?] INFO: task hung in nfsd_nl_threads_get_doit 0 (2) 2026/08/07 07:38
[syzbot] Monthly nfs report (Jul 2025) 0 (1) 2025/07/04 12:38
[syzbot] Monthly nfs report (Jun 2025) 0 (1) 2025/06/03 09:38
▶ ▼ Last patch testing requests (2)
Created Duration User Patch Repo Result
2026/08/07 08:49 4h16m glider@google.com upstream report log
2026/08/06 20:15 6h01m nogikh@google.com upstream report log

Sample crash report:
INFO: task syz-executor115:6008 blocked for more than 15 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor115 state:D stack:27456 pid:6008  tgid:5978  ppid:5975   task_flags:0x400040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7326
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821
 nfsd_nl_threads_get_doit+0x1c0/0x790 fs/nfsd/nfsctl.c:1754
 genl_family_rcv_msg_doit+0x233/0x340 net/netlink/genetlink.c:1114
 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
 genl_rcv_msg+0x614/0x7a0 net/netlink/genetlink.c:1209
 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x7bb/0x940 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:775
 __sock_sendmsg net/socket.c:790 [inline]
 __sys_sendto+0x408/0x5a0 net/socket.c:2252
 __do_sys_sendto net/socket.c:2259 [inline]
 __se_sys_sendto net/socket.c:2255 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2255
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f36365528de
RSP: 002b:00007f3635cfa058 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f3635cfb6c0 RCX: 00007f36365528de
RDX: 0000000000000014 RSI: 00007f3635cfa0d0 RDI: 0000000000000006
RBP: 00007f3635cfa0d0 R08: 00007f3635cfa0c4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3635cfa0c4
R13: 00007f3635cfa1f0 R14: 00007fff54da50e0 R15: 00007fff54da51c8
 </TASK>
INFO: task syz-executor115:6009 blocked for more than 15 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor115 state:D stack:27848 pid:6009  tgid:5978  ppid:5975   task_flags:0x400040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7326
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821
 nfsd_nl_threads_get_doit+0x1c0/0x790 fs/nfsd/nfsctl.c:1754
 genl_family_rcv_msg_doit+0x233/0x340 net/netlink/genetlink.c:1114
 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
 genl_rcv_msg+0x614/0x7a0 net/netlink/genetlink.c:1209
 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x7bb/0x940 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:775
 __sock_sendmsg net/socket.c:790 [inline]
 __sys_sendto+0x408/0x5a0 net/socket.c:2252
 __do_sys_sendto net/socket.c:2259 [inline]
 __se_sys_sendto net/socket.c:2255 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2255
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f36365528de
RSP: 002b:00007f36354f9058 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f36354fa6c0 RCX: 00007f36365528de
RDX: 0000000000000014 RSI: 00007f36354f90d0 RDI: 0000000000000005
RBP: 00007f36354f90d0 R08: 00007f36354f90c4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f36354f90c4
R13: 00007f36354f91f0 R14: 00007fff54da50e0 R15: 00007fff54da51c8
 </TASK>
INFO: task syz-executor115:6010 blocked for more than 16 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor115 state:D stack:27464 pid:6010  tgid:5978  ppid:5975   task_flags:0x400040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7326
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821
 nfsd_nl_threads_get_doit+0x1c0/0x790 fs/nfsd/nfsctl.c:1754
 genl_family_rcv_msg_doit+0x233/0x340 net/netlink/genetlink.c:1114
 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
 genl_rcv_msg+0x614/0x7a0 net/netlink/genetlink.c:1209
 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x7bb/0x940 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:775
 __sock_sendmsg net/socket.c:790 [inline]
 __sys_sendto+0x408/0x5a0 net/socket.c:2252
 __do_sys_sendto net/socket.c:2259 [inline]
 __se_sys_sendto net/socket.c:2255 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2255
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f36365528de
RSP: 002b:00007f3634cf8058 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f3634cf96c0 RCX: 00007f36365528de
RDX: 0000000000000014 RSI: 00007f3634cf80d0 RDI: 0000000000000008
RBP: 00007f3634cf80d0 R08: 00007f3634cf80c4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3634cf80c4
R13: 00007f3634cf81f0 R14: 00007fff54da50e0 R15: 00007fff54da51c8
 </TASK>
INFO: task syz-executor115:6011 blocked for more than 16 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor115 state:D stack:27848 pid:6011  tgid:5978  ppid:5975   task_flags:0x400040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7326
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821
 nfsd_nl_threads_get_doit+0x1c0/0x790 fs/nfsd/nfsctl.c:1754
 genl_family_rcv_msg_doit+0x233/0x340 net/netlink/genetlink.c:1114
 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
 genl_rcv_msg+0x614/0x7a0 net/netlink/genetlink.c:1209
 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x7bb/0x940 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:775
 __sock_sendmsg net/socket.c:790 [inline]
 __sys_sendto+0x408/0x5a0 net/socket.c:2252
 __do_sys_sendto net/socket.c:2259 [inline]
 __se_sys_sendto net/socket.c:2255 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2255
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f36365528de
RSP: 002b:00007f36344f7058 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f36344f86c0 RCX: 00007f36365528de
RDX: 0000000000000014 RSI: 00007f36344f70d0 RDI: 0000000000000007
RBP: 00007f36344f70d0 R08: 00007f36344f70c4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f36344f70c4
R13: 00007f36344f71f0 R14: 00007fff54da50e0 R15: 00007fff54da51c8
 </TASK>
INFO: task syz-executor115:6012 blocked for more than 16 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor115 state:D stack:27848 pid:6012  tgid:5978  ppid:5975   task_flags:0x400040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7326
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821
 nfsd_nl_threads_get_doit+0x1c0/0x790 fs/nfsd/nfsctl.c:1754
 genl_family_rcv_msg_doit+0x233/0x340 net/netlink/genetlink.c:1114
 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
 genl_rcv_msg+0x614/0x7a0 net/netlink/genetlink.c:1209
 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x7bb/0x940 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:775
 __sock_sendmsg net/socket.c:790 [inline]
 __sys_sendto+0x408/0x5a0 net/socket.c:2252
 __do_sys_sendto net/socket.c:2259 [inline]
 __se_sys_sendto net/socket.c:2255 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2255
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f36365528de
RSP: 002b:00007f3633cf6058 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f3633cf76c0 RCX: 00007f36365528de
RDX: 0000000000000014 RSI: 00007f3633cf60d0 RDI: 0000000000000009
RBP: 00007f3633cf60d0 R08: 00007f3633cf60c4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3633cf60c4
R13: 00007f3633cf61f0 R14: 00007fff54da50e0 R15: 00007fff54da51c8
 </TASK>
INFO: task syz-executor115:6073 blocked for more than 17 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor115 state:D stack:28136 pid:6073  tgid:5978  ppid:5975   task_flags:0x400140 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7326
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821
 nfsd_nl_listener_set_doit+0x135/0x1750 fs/nfsd/nfsctl.c:1964
 genl_family_rcv_msg_doit+0x233/0x340 net/netlink/genetlink.c:1114
 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
 genl_rcv_msg+0x614/0x7a0 net/netlink/genetlink.c:1209
 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x7bb/0x940 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:775
 __sock_sendmsg net/socket.c:790 [inline]
 __sys_sendto+0x408/0x5a0 net/socket.c:2252
 __do_sys_sendto net/socket.c:2259 [inline]
 __se_sys_sendto net/socket.c:2255 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2255
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f36365528de
RSP: 002b:00007f36324f0148 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f36324f46c0 RCX: 00007f36365528de
RDX: 0000000000000014 RSI: 00007f36324f21c0 RDI: 000000000000000c
RBP: 0000000000000000 R08: 00007f36324f01b4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000027
R13: 0000000000000011 R14: 00007fff54da50e0 R15: 00007fff54da51c8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/30:
 #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
5 locks held by klogd/4983:
 #0: ffff8880b873b160 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2d/0x160 kernel/sched/core.c:667
 #1: ffff8880b8724440 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x57/0x7d0 kernel/sched/psi.c:933
 #2: ffff8880b8724440 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x57/0x7d0 kernel/sched/psi.c:933
 #3: ffff8880b873b160 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2d/0x160 kernel/sched/core.c:667
 #4: ffff8880b8724440 (psi_seq){-.-.}-{0:0}, at: psi_task_change+0xc9/0x320 kernel/sched/psi.c:919
2 locks held by getty/5383:
 #0: ffff888032c2c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211
2 locks held by syz-executor115/6008:
 #0: ffffffff9009f9e8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8ee8e8c0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_get_doit+0x1c0/0x790 fs/nfsd/nfsctl.c:1754
2 locks held by syz-executor115/6009:
 #0: ffffffff9009f9e8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8ee8e8c0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_get_doit+0x1c0/0x790 fs/nfsd/nfsctl.c:1754
2 locks held by syz-executor115/6010:
 #0: ffffffff9009f9e8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8ee8e8c0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_get_doit+0x1c0/0x790 fs/nfsd/nfsctl.c:1754
2 locks held by syz-executor115/6011:
 #0: ffffffff9009f9e8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8ee8e8c0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_get_doit+0x1c0/0x790 fs/nfsd/nfsctl.c:1754
2 locks held by syz-executor115/6012:
 #0: ffffffff9009f9e8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8ee8e8c0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_get_doit+0x1c0/0x790 fs/nfsd/nfsctl.c:1754
2 locks held by syz-executor115/6013:
 #0: ffffffff9009f9e8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8ee8e8c0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x135/0x1750 fs/nfsd/nfsctl.c:1964
2 locks held by syz-executor115/6073:
 #0: ffffffff9009f9e8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8ee8e8c0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x135/0x1750 fs/nfsd/nfsctl.c:1964

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122
 nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 __sys_info lib/sys_info.c:157 [inline]
 sys_info+0x135/0x170 lib/sys_info.c:165
 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
 watchdog+0xfd7/0x1030 kernel/hung_task.c:561
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64
Code: eb 7c 02 c3 cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d b3 5e 16 00 fb f4 <e9> 4c 07 03 00 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffffff8e807de0 EFLAGS: 00000242
RAX: 00000000000d062f RBX: ffffffff819b5450 RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8e230ceb RDI: ffffffff8c4be380
RBP: ffffffff8e807eb8 R08: ffff8880b86338db R09: 1ffff110170c671b
R10: dffffc0000000000 R11: ffffed10170c671c R12: 0000000000000000
R13: 1ffffffff1d11de8 R14: 1ffffffff1d00fc4 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff888124f42000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056166405b920 CR3: 000000007ff94000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/kernel/process.c:767 [inline]
 default_idle+0x9/0x20 arch/x86/kernel/process.c:768
 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:199 [inline]
 do_idle+0x2e0/0x540 kernel/sched/idle.c:355
 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:454
 rest_init+0x2de/0x300 init/main.c:717
 start_kernel+0x392/0x3e0 init/main.c:1175
 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
 x86_64_start_kernel+0x137/0x1b0 arch/x86/kernel/head64.c:291
 common_startup_64+0x13e/0x157
 </TASK>

Crashes (1704):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/07 18:55 upstream a13307e97d5c aaffb173 .config console log report C ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/08/07 07:37 upstream 364465ab19de aaffb173 .config console log report C ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/07/31 01:33 upstream 3708dd948844 aaffb173 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in nfsd_nl_threads_get_doit
2026/07/30 23:47 upstream 3708dd948844 aaffb173 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in nfsd_nl_threads_get_doit
2026/07/30 18:31 upstream 11028ab62899 aaffb173 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in nfsd_nl_threads_get_doit
2026/07/07 20:46 upstream 0e35b9b6ec0f 76cdc0c0 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: task hung in nfsd_nl_threads_get_doit
2026/06/02 10:53 upstream 6f3ed7fec72f 62fe1528 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in nfsd_nl_threads_get_doit
2026/05/17 05:12 upstream 6916d5703ddf de5aae85 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in nfsd_nl_threads_get_doit
2026/05/10 04:29 upstream 1bfaee9d3351 29233ece .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: task hung in nfsd_nl_threads_get_doit
2026/04/10 20:19 upstream 9a9c8ce300cd 38c8e246 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in nfsd_nl_threads_get_doit
2026/03/03 11:53 upstream af4e9ef3d784 28b83e23 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: task hung in nfsd_nl_threads_get_doit
2024/06/12 22:52 upstream cea2a26553ac 2aa5052f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in nfsd_nl_threads_get_doit
2026/08/03 12:01 net af39eb111ce6 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/07/26 01:13 net 53658c6f3682 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/07/22 13:22 net ba712ecfd942 b561ce9c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/07/20 23:38 net e13caf1c2658 de6a700d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/07/06 23:17 net a0a558ca7e75 88b240e4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/07/06 17:54 net a0a558ca7e75 88b240e4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/07/05 02:43 net d64567434247 fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/26 02:02 net 02f144fbb4c8 432fd51a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/25 22:51 net 02f144fbb4c8 432fd51a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/25 19:16 net 02f144fbb4c8 432fd51a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/25 17:35 net 02f144fbb4c8 432fd51a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/25 16:18 net 02f144fbb4c8 432fd51a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/25 08:48 net 6bd81a5b4e0d cfa969bf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/24 23:25 net d87363b0edfc cfa969bf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/24 22:14 net d87363b0edfc c1da772e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/24 21:06 net d87363b0edfc c1da772e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/24 20:54 net d87363b0edfc c1da772e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/24 16:51 net d87363b0edfc c1da772e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/24 13:39 net d87363b0edfc c1da772e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/24 08:27 net e82d8cc4321c 042555ff .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/24 04:49 net e82d8cc4321c 042555ff .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/24 03:05 net e82d8cc4321c 042555ff .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/24 01:06 net e82d8cc4321c 042555ff .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/23 18:03 net a986fde914d8 4b1d8f01 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/23 12:58 net a986fde914d8 4b1d8f01 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/23 11:30 net a986fde914d8 4b1d8f01 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/23 05:30 net a986fde914d8 5a630be6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/22 23:05 net d07d80b6a129 5a630be6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/22 22:29 net d07d80b6a129 5a630be6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2024/06/23 00:43 net 49bbeb5719c2 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2024/06/21 01:32 net d5a7fc58da03 dac2aa43 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/07/20 09:31 net-next 298bb2b89033 de6a700d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/07/20 05:52 net-next ce6b4d3216b6 72524a66 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/07/20 01:56 net-next ce6b4d3216b6 72524a66 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/07/19 15:46 net-next ce6b4d3216b6 72524a66 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/07/19 12:38 net-next ce6b4d3216b6 72524a66 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/07/18 22:23 net-next ce6b4d3216b6 72524a66 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/07/18 19:33 net-next ce6b4d3216b6 72524a66 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/07/18 03:39 net-next ce6b4d3216b6 72524a66 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/07/13 09:02 net-next f6f3b36c15ed a870962e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/07/12 16:06 net-next f6f3b36c15ed d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/25 03:29 net-next b85966adbf5d cfa969bf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/06/22 19:31 net-next b85966adbf5d 5a630be6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/07/13 06:59 linux-next bee763d5f341 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/07/11 04:48 linux-next bee763d5f341 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in nfsd_nl_threads_get_doit
2026/03/24 12:58 linux-next 09c0f7f1bcdb 74e70d19 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in nfsd_nl_threads_get_doit
* Struck through repros no longer work on HEAD.