INFO: task syz.4.754:8792 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.754 state:D stack:25664 pid:8792 tgid:8789 ppid:5645 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1840/0x57a0 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7283
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0x7c5/0x1590 kernel/locking/mutex.c:820
nfsd_nl_threads_get_doit+0x1c0/0x790 fs/nfsd/nfsctl.c:1738
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:2555
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x7bb/0x940 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1899
sock_sendmsg_nosec net/socket.c:787 [inline]
__sock_sendmsg net/socket.c:802 [inline]
____sys_sendmsg+0x9b9/0xa20 net/socket.c:2699
___sys_sendmsg+0x2a5/0x360 net/socket.c:2753
__sys_sendmsg net/socket.c:2785 [inline]
__do_sys_sendmsg net/socket.c:2790 [inline]
__se_sys_sendmsg net/socket.c:2788 [inline]
__x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2788
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: 0033:0x7fb72c39ce59
RSP: 002b:00007fb72d318028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fb72c615fa0 RCX: 00007fb72c39ce59
RDX: 0000000004040090 RSI: 0000200000000000 RDI: 0000000000000005
RBP: 00007fb72c432d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb72c616038 R14: 00007fb72c615fa0 R15: 00007ffe8a3d0978
Showing all locks held in the system:
3 locks held by rcu_exp_gp_kthr/18:
#0: ffff8880b863b0e0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2d/0x160 kernel/sched/core.c:652
#1: ffff8880b8624588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x57/0x7d0 kernel/sched/psi.c:933
#2: ffffffff9a715650 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x83/0x580 lib/debugobjects.c:845
1 lock held by khungtaskd/31:
#0: ffffffff8e95c780 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e95c780 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8e95c780 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
1 lock held by dhcpcd/5295:
#0: ffffffff8fdc0700 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8fdc0700 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_deladdr+0x1c1/0x790 net/ipv4/devinet.c:670
2 locks held by getty/5388:
#0: ffff8880374f90a0 (&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/0x1380 drivers/tty/n_tty.c:2211
3 locks held by kworker/u9:3/5639:
#0: ffff888054b8c140 ((wq_completion)hci5){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
#0: ffff888054b8c140 ((wq_completion)hci5){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3397
#1: ffffc90003dbfc40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
#1: ffffc90003dbfc40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3397
#2: ffff8880529b8ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1cb/0x3f0 net/bluetooth/hci_sync.c:331
2 locks held by syz.2.405/7406:
#0: ffffffff8fe2fea8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8ec89ba0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x135/0x1750 fs/nfsd/nfsctl.c:1948
2 locks held by syz.4.754/8792:
#0: ffffffff8fe2fea8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8ec89ba0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_get_doit+0x1c0/0x790 fs/nfsd/nfsctl.c:1738
3 locks held by kworker/u8:35/8869:
#0: ffff88813fe7c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
#0: ffff88813fe7c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3397
#1: ffffc900034dfc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
#1: ffffc900034dfc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3397
#2: ffffffff8fdc0700 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313
2 locks held by syz.0.1173/10432:
#0: ffffffff8fe2fea8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8ec89ba0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_version_set_doit+0xcd/0x7a0 fs/nfsd/nfsctl.c:1798
1 lock held by syz.5.1618/12331:
#0: ffffffff8fdc0700 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff8fdc0700 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3442
2 locks held by syz.5.1618/12332:
#0: ffffffff8fe2fea8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8ec89ba0 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x135/0x1750 fs/nfsd/nfsctl.c:1948
2 locks held by syz.8.1621/12349:
#0: ffffffff8fdc0700 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff8fdc0700 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3442
#1: ffffffff8e962aa8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#1: ffffffff8e962aa8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961
1 lock held by syz.3.1624/12357:
#0: ffffffff8fdc0700 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8fdc0700 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8fdc0700 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dellink+0x41b/0x810 net/core/rtnetlink.c:3586
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
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: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+0x389/0x470 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
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 12357 Comm: syz.3.1624 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:should_zap_cows mm/memory.c:1579 [inline]
RIP: 0010:should_zap_folio mm/memory.c:1587 [inline]
RIP: 0010:zap_present_ptes mm/memory.c:1714 [inline]
RIP: 0010:do_zap_pte_range mm/memory.c:1832 [inline]
RIP: 0010:zap_pte_range mm/memory.c:1934 [inline]
RIP: 0010:zap_pmd_range mm/memory.c:2020 [inline]
RIP: 0010:zap_pud_range mm/memory.c:2048 [inline]
RIP: 0010:zap_p4d_range mm/memory.c:2069 [inline]
RIP: 0010:__zap_vma_range+0x157e/0x4c70 mm/memory.c:2109
Code: 28 0b 00 00 eb 05 e8 01 58 af ff b8 01 00 00 00 4c 8b bc 24 90 00 00 00 41 01 c7 e9 46 0f 00 00 e8 e7 57 af ff 42 0f b6 04 23 <84> c0 48 8b 7c 24 70 0f 85 7f 1d 00 00 80 3f 00 48 8b 5c 24 50 74
RSP: 0018:ffffc900078173a0 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 1ffff92000f02eef RCX: ffff888030453e00
RDX: 0000000000000000 RSI: 0000000000066000 RDI: ffffc90007817778
RBP: ffffc90007817690 R08: ffffea0001985d33 R09: 1ffffd4000330ba6
R10: dffffc0000000000 R11: fffff94000330ba7 R12: dffffc0000000000
R13: 0000000000000000 R14: ffff888091e4fb90 R15: 00007f9006f72000
FS: 0000000000000000(0000) GS:ffff8881252b9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe7e1c3418 CR3: 000000003618a000 CR4: 00000000003526f0
Call Trace:
unmap_vmas+0x390/0x550 mm/memory.c:2178
exit_mmap+0x293/0x9f0 mm/mmap.c:1300
__mmput+0x118/0x420 kernel/fork.c:1178
exit_mm+0x1e4/0x2b0 kernel/exit.c:582
do_exit+0x6cd/0x2360 kernel/exit.c:964
do_group_exit+0x22d/0x2f0 kernel/exit.c:1119
get_signal+0x121b/0x12c0 kernel/signal.c:3038
arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
exit_to_user_mode_loop+0xa9/0x6b0 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
do_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f900779ce59
Code: Unable to access opcode bytes at 0x7f900779ce2f.
RSP: 002b:00007f90059f6028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: 000000000000002e RBX: 00007f9007a15fa0 RCX: 00007f900779ce59
RDX: 0000000000000024 RSI: 0000200000000600 RDI: 000000000000000d
RBP: 00007f9007832d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9007a16038 R14: 00007f9007a15fa0 R15: 00007ffc8361edf8