INFO: task syz.0.5627:29687 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.5627 state:D stack:26976 pid:29687 tgid:29683 ppid:17582 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x17d4/0x5630 kernel/sched/core.c:7239
__schedule_loop kernel/sched/core.c:7316 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7331
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7388
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0x7c1/0x1550 kernel/locking/mutex.c:821
nfsd_nl_svc_export_get_reqs_dumpit+0xf7/0xc40 fs/nfsd/export.c:674
genl_dumpit+0x10b/0x1b0 net/netlink/genetlink.c:1026
netlink_dump+0x711/0xee0 net/netlink/af_netlink.c:2331
__netlink_dump_start+0x589/0x7b0 net/netlink/af_netlink.c:2446
genl_family_rcv_msg_dumpit+0x213/0x310 net/netlink/genetlink.c:1075
genl_family_rcv_msg net/netlink/genetlink.c:1191 [inline]
genl_rcv_msg+0x5e1/0x7a0 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+0x7bd/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:800
__sock_sendmsg net/socket.c:815 [inline]
____sys_sendmsg+0x54e/0x850 net/socket.c:2713
___sys_sendmsg+0x2a5/0x360 net/socket.c:2767
__sys_sendmsg net/socket.c:2799 [inline]
__do_sys_sendmsg net/socket.c:2804 [inline]
__se_sys_sendmsg net/socket.c:2802 [inline]
__x64_sys_sendmsg+0x1b1/0x290 net/socket.c:2802
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f872a19e0d9
RSP: 002b:00007f87283f6028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f872a426090 RCX: 00007f872a19e0d9
RDX: 0000000004044810 RSI: 0000200000000180 RDI: 0000000000000007
RBP: 00007f872a235024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f872a426128 R14: 00007f872a426090 R15: 00007ffe20204e88
Showing all locks held in the system:
locks held by khungtaskd/31: 1, last CPU#0:
#0: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6793
locks held by getty/5366: 2, on CPU#1:
#0: ffff888035dde0a0 (&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
locks held by syz.4.5534/29319: 2, on CPU#1:
#0: ffffffff900a70a8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8ee97420 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x135/0x1750 fs/nfsd/nfsctl.c:1964
locks held by syz.0.5627/29687: 3, on CPU#0:
#0: ffffffff900a70a8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffff888055e0d6e8 (nlk_cb_mutex-GENERIC){+.+.}-{4:4}, at: __netlink_dump_start+0xf4/0x7b0 net/netlink/af_netlink.c:2410
#2: ffffffff8ee97420 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_svc_export_get_reqs_dumpit+0xf7/0xc40 fs/nfsd/export.c:674
locks held by syz-executor/30452: 1, on CPU#0:
#0: ffffffff8eb604e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#0: ffffffff8eb604e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
locks held by syz-executor/30545: 2, last CPU#0:
#0: ffff88807656f7e8 (&ei->i_data_sem#2){++++}-{4:4}, at: ext4_release_file+0x15e/0x310 fs/ext4/file.c:178
#1: ffff8880b863b4e0 (&rq->__lock){-.-.}-{2:2}, at: spin_lock_irq include/linux/spinlock.h:377 [inline]
#1: ffff8880b863b4e0 (&rq->__lock){-.-.}-{2:2}, at: delete_from_page_cache_batch+0xeb/0xba0 mm/filemap.c:329
locks held by syz-executor/30548: 2, on CPU#0:
#0: ffff88804ada4ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline]
#0: ffff88804ada4ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x22a/0x5b0 net/bluetooth/hci_core.c:2681
#1: ffffffff8eb604e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#1: ffffffff8eb604e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
locks held by dhcpcd/31712: 1, on CPU#0:
#0: ffff888046c14260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline]
#0: ffff888046c14260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xe90 net/packet/af_packet.c:3229
locks held by dhcpcd/31713: 1, on CPU#0:
#0: ffff888046c10260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline]
#0: ffff888046c10260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xe90 net/packet/af_packet.c:3229
locks held by dhcpcd/31714: 1, on CPU#1:
#0: ffff88808be5e260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline]
#0: ffff88808be5e260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xe90 net/packet/af_packet.c:3229
locks held by dhcpcd/31715: 1, on CPU#1:
#0: ffff888038524260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline]
#0: ffff888038524260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xe90 net/packet/af_packet.c:3229
locks held by dhcpcd/31716: 1, on CPU#0:
#0: ffff88805093e260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline]
#0: ffff88805093e260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xe90 net/packet/af_packet.c:3229
locks held by dhcpcd-run-hook/31721: 1, last CPU#0:
#0: ffffffff8ec32b50 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1548 [inline]
#0: ffffffff8ec32b50 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x10f/0x480 kernel/fork.c:1601
locks held by sed/31722: 1, last CPU#0:
#0: ffff88801b054378 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:554 [inline]
#0: ffff88801b054378 (&mm->mmap_lock){++++}-{4:4}, at: setup_arg_pages+0x30e/0xbd0 fs/exec.c:654
=============================================
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 07/24/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:123
nmi_trigger_cpumask_backtrace+0x17d/0x390 lib/nmi_backtrace.c:66
trigger_all_cpu_backtrace include/linux/nmi.h:164 [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+0x38b/0x480 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: 10669 Comm: kworker/u8:13 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:lockdep_hardirqs_off+0x62/0xd0 kernel/locking/lockdep.c:4528
Code: 65 8b 05 29 8a 97 07 85 c0 74 56 65 4c 8b 35 ad 49 97 07 48 c7 c7 ad 7c 25 8e e8 59 1c 00 00 65 c7 05 06 8a 97 07 00 00 00 00 <49> 89 9e 50 0b 00 00 41 8b 86 40 0b 00 00 ff c0 41 89 86 40 0b 00
RSP: 0018:ffffc90000007c40 EFLAGS: 00000002
RAX: 0000000000000000 RBX: ffffffff8bdb2d5a RCX: 0000000000000102
RDX: 0000000000000000 RSI: ffffffff8e257cad RDI: ffffffff8c4cd780
RBP: ffff88802f9b9e00 R08: ffffc90000007cef R09: 0000000000000000
R10: ffffc90000007cc8 R11: fffff52000000f9e R12: 0000000000000000
R13: ffff88802f9b9000 R14: ffff88807f770000 R15: ffff88807f0b6820
FS: 0000000000000000(0000) GS:ffff888124f24000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa300d5c4e8 CR3: 000000007f6dc000 CR4: 00000000003526f0
Call Trace:
trace_hardirqs_off+0x12/0x40 kernel/trace/trace_preemptirq.c:104
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:153 [inline]
_raw_spin_lock_irqsave+0x1a/0x60 kernel/locking/spinlock.c:181
__debug_check_no_obj_freed lib/debugobjects.c:1160 [inline]
debug_check_no_obj_freed+0xcb/0x450 lib/debugobjects.c:1201
slab_free_hook mm/slub.c:2608 [inline]
__rcu_free_sheaf_prepare+0xdf/0x2a0 mm/slub.c:2928
rcu_free_sheaf+0x31/0x200 mm/slub.c:5978
rcu_do_batch kernel/rcu/tree.c:2645 [inline]
rcu_core+0x794/0x10b0 kernel/rcu/tree.c:2897
handle_softirqs+0x226/0x860 kernel/softirq.c:645
do_softirq+0x77/0xd0 kernel/softirq.c:546
__local_bh_enable_ip+0x100/0x140 kernel/softirq.c:473
spin_unlock_bh include/linux/spinlock.h:407 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:816 [inline]
nsim_dev_trap_report_work+0x7a4/0xb40 drivers/net/netdevsim/dev.c:847
process_one_work kernel/workqueue.c:3322 [inline]
process_scheduled_works+0xa88/0x14c0 kernel/workqueue.c:3405
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
kthread+0x38b/0x480 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