INFO: task syz.4.2869:17312 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.2869 state:D stack:27104 pid:17312 tgid:17311 ppid:5617 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5526 [inline]
__schedule+0x17db/0x58f0 kernel/sched/core.c:7276
__schedule_loop kernel/sched/core.c:7353 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7368
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7425
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0x7c1/0x1550 kernel/locking/mutex.c:821
nfsd_nl_svc_export_set_reqs_doit+0x132/0x1450 fs/nfsd/export.c:1056
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:2575
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
netlink_unicast_kernel net/netlink/af_netlink.c:1338 [inline]
netlink_unicast+0x7bd/0x940 net/netlink/af_netlink.c:1364
netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1919
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: 0033:0x7f1feb19e159
RSP: 002b:00007f1fec022028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f1feb425fa0 RCX: 00007f1feb19e159
RDX: 0000000004008090 RSI: 0000200000000040 RDI: 0000000000000030
RBP: 00007f1feb23506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1feb426038 R14: 00007f1feb425fa0 R15: 00007fffb945db78
Showing all locks held in the system:
locks held by khungtaskd/31: 1, last CPU#0:
#0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871
locks held by getty/5375: 2, on CPU#0:
#0: ffff88803557e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211
locks held by syz.3.2715/16657: 2, on CPU#0:
#0: ffffffff902c3628 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8f09f500 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x53d/0x1ab0 fs/nfsd/nfsctl.c:2057
locks held by syz.4.2869/17312: 2, on CPU#0:
#0: ffffffff902c3628 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8f09f500 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_svc_export_set_reqs_doit+0x132/0x1450 fs/nfsd/export.c:1056
locks held by syz.0.3732/20790: 2, on CPU#0:
#0: ffffffff902c3628 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8f09f500 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_cache_flush_doit+0xb5/0x1b0 fs/nfsd/nfsctl.c:2319
locks held by syz-executor/21058: 2, on CPU#0:
#0: ffffffff902c3628 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff902c3460 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
#1: ffffffff902c3460 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
#1: ffffffff902c3460 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
locks held by syz.6.3801/21068: 1, on CPU#0:
#0: ffff888068ad8140 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline]
#0: ffff888068ad8140 (&dev->mutex){....}-{4:4}, at: nfc_unregister_rfkill+0x63/0x280 net/nfc/core.c:1166
locks held by syz.6.3801/21072: 4, on CPU#0:
#0: ffffffff902c3628 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff902c3460 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
#1: ffffffff902c3460 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
#1: ffffffff902c3460 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
#2: ffff888068ad8140 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline]
#2: ffff888068ad8140 (&dev->mutex){....}-{4:4}, at: nfc_dev_up+0x3c/0x350 net/nfc/core.c:95
#3: ffff88807b24e348 (&ndev->req_lock){+.+.}-{4:4}, at: nci_open_device net/nfc/nci/core.c:478 [inline]
#3: ffff88807b24e348 (&ndev->req_lock){+.+.}-{4:4}, at: nci_dev_up+0xa3/0xdc0 net/nfc/nci/core.c:643
locks held by syz.5.3804/21082: 2, on CPU#0:
#0: ffffffff902c3628 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff902c3460 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
#1: ffffffff902c3460 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
#1: ffffffff902c3460 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
locks held by syz.5.3804/21084: 2, on CPU#0:
#0: ffffffff902c3628 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff902c3460 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
#1: ffffffff902c3460 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
#1: ffffffff902c3460 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
locks held by syz.2.3811/21116: 2, on CPU#1:
#0: ffffffff902c3628 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff902c3460 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
#1: ffffffff902c3460 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
#1: ffffffff902c3460 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
locks held by syz.2.3811/21117: 2, on CPU#0:
#0: ffffffff902c3628 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff902c3460 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
#1: ffffffff902c3460 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
#1: ffffffff902c3460 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
locks held by syz.2.3811/21118: 2, on CPU#0:
#0: ffffffff902c3628 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff902c3460 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
#1: ffffffff902c3460 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
#1: ffffffff902c3460 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
locks held by syz.1.3815/21133: 2, last CPU#1:
#0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: lock_vma_under_rcu+0x116/0x500 mm/mmap_lock.c:303
#1: ffff8880b873bb20 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2d/0x160 kernel/sched/core.c:677
=============================================
NMI backtrace for cpu 0
CPU: 0 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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 21133 Comm: syz.1.3815 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline]
RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:114 [inline]
RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:128 [inline]
RIP: 0010:lock_acquire+0xb9/0x350 kernel/locking/lockdep.c:5938
Code: f2 11 85 c0 0f 85 d5 00 00 00 65 48 8b 2d a7 c6 f1 11 83 bd a4 0b 00 00 00 0f 85 c0 00 00 00 48 89 5c 24 08 4c 89 fb 9c 41 5f 48 c7 c7 bd 14 49 8e e8 aa 39 42 0a 65 ff 05 2b 0b f2 11 45 31
RSP: 0000:ffffc90000a18e48 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 8000000000000103
RDX: 0000000000000000 RSI: ffffffff89b550dc RDI: 1ffffffff1dab914
RBP: ffff8880773c9f40 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff20f4690 R12: ffffffff8ed5c8a0
R13: 0000000000000002 R14: 0000000000000000 R15: 0000000000000246
FS: 00005555787da500(0000) GS:ffff888124dd1000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f36c4414560 CR3: 00000000307ba000 CR4: 00000000003526f0
Call Trace:
rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
rcu_read_lock include/linux/rcupdate.h:849 [inline]
net_tx_action+0x5dc/0xc30 net/core/dev.c:5883
handle_softirqs+0x226/0x860 kernel/softirq.c:645
__do_softirq kernel/softirq.c:679 [inline]
invoke_softirq kernel/softirq.c:519 [inline]
__irq_exit_rcu+0xcb/0x220 kernel/softirq.c:758
irq_exit_rcu+0x9/0x30 kernel/softirq.c:775
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:__mod_memcg_lruvec_state+0xd3/0x360 mm/memcontrol.c:973
Code: b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 4c 89 ff e8 50 1c f8 ff 4d 8b 3f 41 80 fd 3a 0f 83 83 01 00 00 65 4f 01 74 ef 18 <49> 83 c4 08 4c 89 e0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80
RSP: 0000:ffffc900067df918 EFLAGS: 00000286
RAX: 1ffff1100d1f6990 RBX: 0000000000000011 RCX: dffffc0000000000
RDX: 0000000000000001 RSI: ffffffff8c1e6240 RDI: ffffffff8c6d9c80
RBP: 0000000000000001 R08: ffffffff823fbea5 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff94000336f19 R12: ffff888068fbcec0
R13: 000000000000000e R14: 0000000000000001 R15: 0000607edafb3000
mod_memcg_lruvec_state+0x1e7/0x270 mm/memcontrol.c:995
mod_lruvec_state mm/memcontrol.c:1018 [inline]
lruvec_stat_mod_folio+0x239/0x3e0 mm/memcontrol.c:1038
__folio_mod_stat+0x6b/0x1c0 mm/rmap.c:1342
folio_add_new_anon_rmap+0x58e/0x1370 mm/rmap.c:1702
wp_page_copy mm/memory.c:4074 [inline]
do_wp_page+0x3c95/0x4b80 mm/memory.c:4472
handle_pte_fault mm/memory.c:6582 [inline]
__handle_mm_fault mm/memory.c:6707 [inline]
handle_mm_fault+0x15d7/0x3750 mm/memory.c:6876
do_user_addr_fault+0xa4f/0x1340 arch/x86/mm/fault.c:1343
handle_page_fault arch/x86/mm/fault.c:1483 [inline]
exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595
RIP: 0033:0x7f36c40517fc
Code: 23 83 c0 01 44 39 d0 75 dc 48 89 f0 25 ff 1f 00 00 49 89 34 c1 41 88 3c 00 31 c0 c3 66 90 41 38 3c 10 74 0b 41 88 3c 10 31 c0 <49> 89 34 d1 c3 b8 01 00 00 00 c3 66 0f 1f 84 00 00 00 00 00 48 83
RSP: 002b:00007ffcd37bb098 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffffff81b864ac RCX: 0000000000000000
RDX: 00000000000004ac RSI: ffffffff81b864ac RDI: 0000000000000000
RBP: 0000000000000000 R08: 00007f36c4410000 R09: 00007f36c4412000
R10: 0000000081b864b0 R11: 0000000000000000 R12: 00007f36c4426038
R13: 000000000000000b R14: ffffffff81b864ac R15: 00007f36c4f55720