syzbot


INFO: task hung in nfsd_nl_rpc_status_get_dumpit

Status: upstream: reported on 2024/07/20 21:33
Subsystems: nfs
[Documentation on labels]
Reported-by: syzbot+68f089d6e18e8b1d41eb@syzkaller.appspotmail.com
First crash: 596d, last: 1h23m
Discussions (3)
Title Replies (including bot) Last reply
[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
[syzbot] [nfs?] INFO: task hung in nfsd_nl_rpc_status_get_dumpit 0 (1) 2024/07/20 21:33

Sample crash report:
INFO: task syz.5.7214:24064 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.7214      state:D stack:26136 pid:24064 tgid:24061 ppid:21571  task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5295 [inline]
 __schedule+0x1585/0x5340 kernel/sched/core.c:6907
 __schedule_loop kernel/sched/core.c:6989 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7004
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061
 __mutex_lock_common kernel/locking/mutex.c:692 [inline]
 __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776
 nfsd_nl_rpc_status_get_dumpit+0xdc/0x1410 fs/nfsd/nfsctl.c:1484
 genl_dumpit+0x10b/0x1b0 net/netlink/genetlink.c:1027
 netlink_dump+0x722/0xe80 net/netlink/af_netlink.c:2325
 __netlink_dump_start+0x5cb/0x7e0 net/netlink/af_netlink.c:2440
 genl_family_rcv_msg_dumpit+0x213/0x310 net/netlink/genetlink.c:1076
 genl_family_rcv_msg net/netlink/genetlink.c:1192 [inline]
 genl_rcv_msg+0x5e8/0x7a0 net/netlink/genetlink.c:1210
 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x80f/0x9b0 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg net/socket.c:742 [inline]
 ____sys_sendmsg+0xa68/0xad0 net/socket.c:2592
 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2646
 __sys_sendmsg net/socket.c:2678 [inline]
 __do_sys_sendmsg net/socket.c:2683 [inline]
 __se_sys_sendmsg net/socket.c:2681 [inline]
 __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2681
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fce8339bf79
RSP: 002b:00007fce84309028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fce83615fa0 RCX: 00007fce8339bf79
RDX: 0000000000000000 RSI: 0000200000000180 RDI: 0000000000000003
RBP: 00007fce834327e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fce83616038 R14: 00007fce83615fa0 R15: 00007ffc99dbfb58
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/32:
 #0: ffffffff8e7603e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
 #0: ffffffff8e7603e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
 #0: ffffffff8e7603e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5581:
 #0: ffff888032cfa0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211
2 locks held by syz.8.4728/17632:
 #0: ffffffff8fc35970 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
 #1: ffffffff8ea84de8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x141/0x16c0 fs/nfsd/nfsctl.c:1893
3 locks held by syz.5.7214/24064:
 #0: ffffffff8fc35970 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
 #1: ffff888054cf86f0 (nlk_cb_mutex-GENERIC){+.+.}-{4:4}, at: __netlink_dump_start+0xfe/0x7e0 net/netlink/af_netlink.c:2404
 #2: ffffffff8ea84de8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_rpc_status_get_dumpit+0xdc/0x1410 fs/nfsd/nfsctl.c:1484
2 locks held by syz.3.9485/29355:
 #0: ffffffff8fc35970 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
 #1: ffffffff8ea84de8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_get_doit+0x1c0/0x790 fs/nfsd/nfsctl.c:1683

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 32 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:161 [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:346 [inline]
 watchdog+0xfd9/0x1030 kernel/hung_task.c:515
 kthread+0x388/0x470 kernel/kthread.c:467
 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: 3e 6f 02 e9 8e 52 65 f5 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 43 6d 1e 00 fb f4 <e9> 67 52 65 f5 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffc90000197e20 EFLAGS: 00000246
RAX: 0000000000089499 RBX: ffffffff819a779d RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8deec0f1 RDI: ffffffff8c279080
RBP: ffffc90000197f10 R08: ffff8880b873395b R09: 1ffff110170e672b
R10: dffffc0000000000 R11: ffffed10170e672c R12: ffffffff90112bb0
R13: 1ffff11003ad0000 R14: 0000000000000001 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff888125572000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c360788 CR3: 0000000055164000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/kernel/process.c:766 [inline]
 default_idle+0x9/0x20 arch/x86/kernel/process.c:767
 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:191 [inline]
 do_idle+0x1bd/0x500 kernel/sched/idle.c:332
 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:430
 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
 common_startup_64+0x13e/0x147
 </TASK>

Crashes (1228):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/02/14 10:45 upstream 770aaedb461a 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/13 17:07 upstream cee73b1e840c 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/08 13:39 upstream e7aa57247700 4c131dc4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/01 13:30 upstream 162b42445b58 6b8752f2 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/20 01:00 upstream 24d479d26b25 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/19 01:48 upstream 24d479d26b25 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2025/11/13 06:08 upstream e927c520e1ba 07e030de .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2024/07/20 03:50 upstream d7e78951a8b8 b88348e9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2024/07/16 21:17 upstream 408323581b72 215bec2d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2024/07/09 03:53 upstream 4376e966ecb7 bc23a442 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/13 20:11 net 8383522821c6 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/12 05:23 net bf9cf80cab81 76a109e2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/08 17:11 net 6d2f142b1e4b 4c131dc4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/07 06:28 net 5d41f95f5d0b f20fc9f9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/06 07:54 net c89477ad7944 f03c4191 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/06 06:53 net c89477ad7944 f03c4191 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/06 05:01 net c89477ad7944 f03c4191 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/05 21:36 net 7d6ba706ae5e 4936e85c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/05 20:19 net 7d6ba706ae5e 4936e85c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/05 18:15 net 7d6ba706ae5e 4936e85c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/05 16:24 net 7d6ba706ae5e 4936e85c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/05 15:03 net 7d6ba706ae5e 4936e85c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/02 11:44 net fdf3f6800be3 018ebef2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/01 06:08 net fdf3f6800be3 35764559 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/01 03:20 net fdf3f6800be3 35764559 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/01 00:56 net fdf3f6800be3 35764559 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/31 16:05 net 6d06bc83a5ae c75a2f6e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/29 21:00 net 085820673225 aeb6fdd5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/25 07:08 net 8016dc5ee19a 40acda8a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/19 14:17 net f40ddcc0c0ca d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/19 00:28 net f40ddcc0c0ca d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/18 20:31 net f40ddcc0c0ca d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/18 00:14 net a74c7a58ca2c d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/17 22:00 net a74c7a58ca2c d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/17 20:45 net a74c7a58ca2c d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/17 17:13 net a74c7a58ca2c d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/17 11:58 net a74c7a58ca2c d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/17 09:45 net a74c7a58ca2c d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/17 08:22 net a74c7a58ca2c d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/17 05:47 net a74c7a58ca2c d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/17 03:07 net a74c7a58ca2c d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/17 00:36 net a74c7a58ca2c d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/16 23:31 net a74c7a58ca2c d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/09 10:17 net-next 57be33f85e36 4c131dc4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/09 07:24 net-next 57be33f85e36 4c131dc4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/09 06:00 net-next 57be33f85e36 4c131dc4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/08 10:32 net-next 57be33f85e36 4c131dc4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/08 06:29 net-next 57be33f85e36 4c131dc4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/08 01:35 net-next 57be33f85e36 4c131dc4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/04 12:15 net-next 667539f6dce2 42b01fab .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/30 11:37 net-next 70e9a5760abf bfa73b7b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/22 14:11 net-next b6d5a62231ac 2367ed1e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/22 10:44 net-next 1b58c94e9cf9 101dad69 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/22 09:32 net-next 1b58c94e9cf9 101dad69 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/02/15 04:36 linux-next 635c467cc14e 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2026/01/24 01:11 linux-next ca3a02fda4da 4f25b9b4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in nfsd_nl_rpc_status_get_dumpit
2025/12/29 12:51 linux-next cc3aa43b44bd d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in nfsd_nl_rpc_status_get_dumpit
* Struck through repros no longer work on HEAD.