INFO: task syz.1.3822:19288 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.3822 state:D stack:26984 pid:19288 tgid:19287 ppid:16123 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7026
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760
nfsd_nl_listener_set_doit+0x137/0x1690 fs/nfsd/nfsctl.c:1880
genl_family_rcv_msg_doit+0x215/0x300 net/netlink/genetlink.c:1115
genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
genl_rcv_msg+0x60e/0x790 net/netlink/genetlink.c:1210
netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1346
netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg+0x21c/0x270 net/socket.c:742
____sys_sendmsg+0x505/0x830 net/socket.c:2630
___sys_sendmsg+0x21f/0x2a0 net/socket.c:2684
__sys_sendmsg net/socket.c:2716 [inline]
__do_sys_sendmsg net/socket.c:2721 [inline]
__se_sys_sendmsg net/socket.c:2719 [inline]
__x64_sys_sendmsg+0x19b/0x260 net/socket.c:2719
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f57d658f6c9
RSP: 002b:00007f57d7448038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f57d67e5fa0 RCX: 00007f57d658f6c9
RDX: 0000000020048000 RSI: 0000200000000000 RDI: 0000000000000003
RBP: 00007f57d6611f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f57d67e6038 R14: 00007f57d67e5fa0 R15: 00007ffd3d320a48
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8df3d660 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df3d660 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8df3d660 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5591:
#0: ffff88814db0b0a0 (&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+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by udevd/10824:
#0: ffff888143379358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945
1 lock held by udevd/11288:
#0: ffff888024d61358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945
2 locks held by syz.2.1770/12167:
#0: ffffffff8f331590 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e226ee8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x137/0x1690 fs/nfsd/nfsctl.c:1880
2 locks held by syz.1.3822/19288:
#0: ffffffff8f331590 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e226ee8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x137/0x1690 fs/nfsd/nfsctl.c:1880
2 locks held by syz.5.4942/23174:
#0: ffffffff8f331590 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e226ee8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x137/0x1690 fs/nfsd/nfsctl.c:1880
2 locks held by syz.0.4951/23197:
#0: ffffffff8f2cb708 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff8f2cb708 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436
#1: ffffffff8df430f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#1: ffffffff8df430f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:957
2 locks held by syz.3.4954/23201:
#0: ffffffff8f7d1a30 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8f7d1a30 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8f7d1a30 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8f2cb708 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8f2cb708 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8f2cb708 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8e9/0x1c80 net/core/rtnetlink.c:4064
=============================================
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 10/25/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
watchdog+0xf60/0xfa0 kernel/hung_task.c:495
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 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: 23198 Comm: syz.7.4952 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__lock_acquire+0x6dc/0xd20 kernel/locking/lockdep.c:5143
Code: 00 83 3d a6 36 dc 17 00 75 13 48 63 44 24 20 48 0f a3 05 f7 a6 d8 11 0f 83 15 05 00 00 31 ed 48 8b 3c 24 4c 8b bf 20 0b 00 00 <48> 83 7c 24 28 00 75 1e 83 3d 75 36 dc 17 00 0f 95 c0 49 83 ff ff
RSP: 0018:ffffc90003ce71e8 EFLAGS: 00000046
RAX: 000000000000001a RBX: 0000000000000003 RCX: ffffffff93171780
RDX: 0000000000000008 RSI: ffff88802db26668 RDI: ffff88802db25ac0
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8230ecfa
R10: dffffc0000000000 R11: fffff940001aa879 R12: 0000000000000003
R13: 0000000000000001 R14: ffff88802db26668 R15: 20665b02c0d328d5
FS: 0000000000000000(0000) GS:ffff88812613b000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f41561b12f8 CR3: 0000000077fa2000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock_sched include/linux/rcupdate.h:958 [inline]
pfn_valid+0xd6/0x490 include/linux/mmzone.h:2187
page_table_check_clear+0x21/0x700 mm/page_table_check.c:70
ptep_get_and_clear_full arch/x86/include/asm/jump_label.h:-1 [inline]
get_and_clear_full_ptes include/linux/pgtable.h:725 [inline]
zap_present_folio_ptes mm/memory.c:1627 [inline]
zap_present_ptes mm/memory.c:1709 [inline]
do_zap_pte_range mm/memory.c:1810 [inline]
zap_pte_range mm/memory.c:1854 [inline]
zap_pmd_range mm/memory.c:1946 [inline]
zap_pud_range mm/memory.c:1975 [inline]
zap_p4d_range mm/memory.c:1996 [inline]
unmap_page_range+0x344b/0x4370 mm/memory.c:2017
unmap_single_vma mm/memory.c:2060 [inline]
unmap_vmas+0x399/0x580 mm/memory.c:2104
exit_mmap+0x240/0xb40 mm/mmap.c:1280
__mmput+0x118/0x430 kernel/fork.c:1133
exit_mm+0x1da/0x2c0 kernel/exit.c:582
do_exit+0x648/0x2300 kernel/exit.c:954
do_group_exit+0x21c/0x2d0 kernel/exit.c:1107
get_signal+0x1285/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0xa0/0x790 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x72/0x130 kernel/entry/common.c:40
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7feab138f6c9
Code: Unable to access opcode bytes at 0x7feab138f69f.
RSP: 002b:00007feab2295038 EFLAGS: 00000246 ORIG_RAX: 0000000000000013
RAX: fffffffffffffe00 RBX: 00007feab15e5fa0 RCX: 00007feab138f6c9
RDX: 0000000000000002 RSI: 00002000000001c0 RDI: 0000000000000004
RBP: 00007feab1411f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007feab15e6038 R14: 00007feab15e5fa0 R15: 00007ffd130bea58