INFO: task syz.5.3225:18833 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.3225 state:D stack:26080 pid:18833 tgid:18832 ppid:13527 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:776
nfsd_nl_threads_get_doit+0x1b6/0x6f0 fs/nfsd/nfsctl.c:1678
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:2550
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg+0x21c/0x270 net/socket.c:742
____sys_sendmsg+0x505/0x820 net/socket.c:2592
___sys_sendmsg+0x21f/0x2a0 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+0x19b/0x260 net/socket.c:2681
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd8c458f749
RSP: 002b:00007fd8c5489038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fd8c47e5fa0 RCX: 00007fd8c458f749
RDX: 0000000020048000 RSI: 0000200000000000 RDI: 0000000000000007
RBP: 00007fd8c4613f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd8c47e6038 R14: 00007fd8c47e5fa0 R15: 00007fffe431f268
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8df41aa0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5592:
#0: ffff88814dcf40a0 (&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+0x449/0x1460 drivers/tty/n_tty.c:2211
2 locks held by syz.1.1744/12899:
#0: ffffffff8f379eb0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e2379a8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x137/0x1660 fs/nfsd/nfsctl.c:1886
1 lock held by syz-executor/17808:
2 locks held by syz.5.3225/18833:
#0: ffffffff8f379eb0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e2379a8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_get_doit+0x1b6/0x6f0 fs/nfsd/nfsctl.c:1678
1 lock held by syz-executor/19319:
2 locks held by syz.6.3635/20537:
#0: ffffffff8f379eb0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e2379a8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x137/0x1660 fs/nfsd/nfsctl.c:1886
1 lock held by syz.8.4823/25050:
1 lock held by syz.8.4823/25051:
=============================================
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+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:160 [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+0xf95/0xfe0 kernel/hung_task.c:515
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 19319 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:separate_irq_context kernel/locking/lockdep.c:4703 [inline]
RIP: 0010:__lock_acquire+0x736/0x2cf0 kernel/locking/lockdep.c:5221
Code: 0b 00 00 4d 85 ff 0f 84 8e 00 00 00 41 83 ff 31 0f 83 ca 23 00 00 4b 8d 04 bf 4d 89 ec 41 8b 6d 20 48 8b 4c 24 20 8b 44 c1 f8 <31> e8 25 00 60 00 00 0f 95 c1 89 0c 24 31 c9 f7 d8 48 19 c9 48 09
RSP: 0018:ffffc90000007768 EFLAGS: 00000083
RAX: 00000000000a4007 RBX: 8d12e597aaaf4992 RCX: ffff888033daa9b0
RDX: 0000000000000008 RSI: ffff888033daaa50 RDI: ffff888033da9e80
RBP: 00000000000a4007 R08: ffffffff81d027d6 R09: ffffffff8df41aa0
R10: ffffc90000007ab8 R11: ffffffff81acf4d0 R12: ffff888033daaa50
R13: ffff888033daaa50 R14: ffff888033da9e80 R15: 0000000000000004
FS: 000055557add7500(0000) GS:ffff888125e1c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1896da6f40 CR3: 000000007cb9a000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x107/0x340 kernel/locking/lockdep.c:5868
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
bpf_has_frame_pointer+0x46/0x390 kernel/bpf/core.c:768
orc_bpf_find arch/x86/kernel/unwind_orc.c:188 [inline]
orc_find arch/x86/kernel/unwind_orc.c:253 [inline]
unwind_next_frame+0x452/0x23d0 arch/x86/kernel/unwind_orc.c:510
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:340 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4953 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
kmem_cache_alloc_noprof+0x37d/0x710 mm/slub.c:5270
sigqueue_alloc kernel/signal.c:455 [inline]
__send_signal_locked+0x22a/0xeb0 kernel/signal.c:1087
do_send_sig_info kernel/signal.c:1269 [inline]
group_send_sig_info+0x1fd/0x260 kernel/signal.c:1419
do_bpf_send_signal+0xa9/0x1c0 kernel/trace/bpf_trace.c:813
irq_work_single+0xe1/0x240 kernel/irq_work.c:221
irq_work_run_list kernel/irq_work.c:252 [inline]
irq_work_run+0xe9/0x230 kernel/irq_work.c:261
__sysvec_irq_work+0x98/0x3a0 arch/x86/kernel/irq_work.c:22
instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline]
sysvec_irq_work+0x9e/0xc0 arch/x86/kernel/irq_work.c:17
asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:733
RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:37 [inline]
RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:139 [inline]
RIP: 0010:wrmsrq arch/x86/include/asm/msr.h:199 [inline]
RIP: 0010:native_apic_msr_write+0x39/0x50 arch/x86/include/asm/apic.h:212
Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 e9 90 a1 ea 09 cc f3 0f 1e fa 89 f6 31 d2 e9 c2 1e 55 03 66
RSP: 0018:ffffc90002f97b28 EFLAGS: 00000246
RAX: 00000000000000f6 RBX: 0000000000000200 RCX: 000000000000083f
RDX: 0000000000000000 RSI: 00000000000000f6 RDI: 000000000000083f
RBP: ffffc90002f97c00 R08: ffffc90002f97b87 R09: 1ffff920005f2f70
R10: dffffc0000000000 R11: fffff520005f2f71 R12: ffff8880b8631c01
R13: 0000000000000000 R14: 0000000000000000 R15: ffff8880b8631c70
__apic_send_IPI_self arch/x86/include/asm/apic.h:459 [inline]
arch_irq_work_raise+0x6d/0x80 arch/x86/kernel/irq_work.c:31
irq_work_raise kernel/irq_work.c:84 [inline]
__irq_work_queue_local+0x1d7/0x530 kernel/irq_work.c:112
irq_work_queue+0x99/0x140 kernel/irq_work.c:124
bpf_send_signal_common+0x39d/0x530 kernel/trace/bpf_trace.c:871
____bpf_send_signal kernel/trace/bpf_trace.c:880 [inline]
bpf_send_signal+0x1d/0x30 kernel/trace/bpf_trace.c:878
bpf_prog_948316cddd0b7b1c+0x41/0x49
bpf_dispatcher_nop_func include/linux/bpf.h:1378 [inline]
__bpf_prog_run include/linux/filter.h:723 [inline]
bpf_prog_run include/linux/filter.h:730 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2075 [inline]
bpf_trace_run2+0x284/0x4c0 kernel/trace/bpf_trace.c:2116
__bpf_trace_sys_enter+0x38/0x60 include/trace/events/syscalls.h:18
__do_trace_sys_enter include/trace/events/syscalls.h:18 [inline]
trace_sys_enter+0x9a/0xf0 include/trace/events/syscalls.h:18
syscall_trace_enter+0xf9/0x160 kernel/entry/syscall-common.c:53
syscall_enter_from_user_mode_work include/linux/entry-common.h:78 [inline]
syscall_enter_from_user_mode include/linux/entry-common.h:109 [inline]
do_syscall_64+0xc5/0xf80 arch/x86/entry/syscall_64.c:90
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fde28f2b829
Code: 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 04 25
RSP: 002b:00007fffbac165c0 EFLAGS: 00000293 ORIG_RAX: 000000000000000f
RAX: ffffffffffffffda RBX: 00000000000003e9 RCX: 00007fde28f2b829
RDX: 00007fffbac165c0 RSI: 00007fffbac166f0 RDI: 0000000000000011
RBP: 00007fffbac16bcc R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000001388
R13: 00000000000927c0 R14: 00000000000b5591 R15: 00007fffbac16c20