INFO: task syz.5.1681:14735 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.1681 state:D stack:26808 pid:14735 tgid:14733 ppid:10644 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x81b/0x1060 kernel/locking/mutex.c:760
nfsd_nl_threads_set_doit+0x687/0xbc0 fs/nfsd/nfsctl.c:1629
genl_family_rcv_msg_doit+0x209/0x2f0 net/netlink/genetlink.c:1115
genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
genl_rcv_msg+0x55c/0x800 net/netlink/genetlink.c:1210
netlink_rcv_skb+0x158/0x420 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+0x5a7/0x870 net/netlink/af_netlink.c:1346
netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1896
sock_sendmsg_nosec net/socket.c:714 [inline]
__sock_sendmsg net/socket.c:729 [inline]
____sys_sendmsg+0xa98/0xc70 net/socket.c:2614
___sys_sendmsg+0x134/0x1d0 net/socket.c:2668
__sys_sendmsg+0x16d/0x220 net/socket.c:2700
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc85458eba9
RSP: 002b:00007fc855455038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fc8547d5fa0 RCX: 00007fc85458eba9
RDX: 0000000000040010 RSI: 00002000000000c0 RDI: 0000000000000007
RBP: 00007fc854611e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc8547d6038 R14: 00007fc8547d5fa0 R15: 00007ffe99709178
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e5c1420 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e5c1420 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e5c1420 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
3 locks held by kworker/u10:10/7577:
2 locks held by getty/8127:
#0: ffff88803522d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000358b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
2 locks held by syz.6.1678/14719:
#0: ffffffff9042be10 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e9d9c88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xd5/0x1b10 fs/nfsd/nfsctl.c:1919
2 locks held by syz.5.1681/14735:
#0: ffffffff9042be10 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e9d9c88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x687/0xbc0 fs/nfsd/nfsctl.c:1629
2 locks held by syz.2.1776/15247:
#0: ffff8880335a00e0 (&type->s_umount_key#51){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff8880335a00e0 (&type->s_umount_key#51){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff8880335a00e0 (&type->s_umount_key#51){++++}-{4:4}, at: deactivate_super fs/super.c:506 [inline]
#0: ffff8880335a00e0 (&type->s_umount_key#51){++++}-{4:4}, at: deactivate_super+0xd6/0x100 fs/super.c:503
#1: ffffffff8e9d9c88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:596
6 locks held by kworker/u10:11/15793:
#0: ffff88801c6fe948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc9000d037d10 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
#2: ffffffff90372650 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xad/0x890 net/core/net_namespace.c:658
#3: ffff888059d400e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline]
#3: ffff888059d400e8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline]
#3: ffff888059d400e8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x12c/0x2b0 net/devlink/core.c:506
#4: ffff888059d41250 (&devlink->lock_key#8){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:276 [inline]
#4: ffff888059d41250 (&devlink->lock_key#8){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline]
#4: ffff888059d41250 (&devlink->lock_key#8){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x136/0x2b0 net/devlink/core.c:506
#5: ffffffff8e5cc880 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x6e0 kernel/rcu/tree.c:3815
2 locks held by syz.9.2017/16527:
#0: ffffffff9042be10 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e9d9c88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x687/0xbc0 fs/nfsd/nfsctl.c:1629
1 lock held by syz.1.2081/16939:
#0: ffffffff8e5cc9b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:343
1 lock held by syz.7.2085/16969:
#0: ffffffff8e5cc9b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x284/0x3c0 kernel/rcu/tree_exp.h:311
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G U syzkaller #0 PREEMPT(full)
Tainted: [U]=USER
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
watchdog+0xf0e/0x1260 kernel/hung_task.c:491
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x56d/0x730 arch/x86/kernel/process.c:148
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: 10 Comm: kworker/0:1 Tainted: G U syzkaller #0 PREEMPT(full)
Tainted: [U]=USER
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: events drain_vmap_area_work
RIP: 0010:debug_smp_processor_id+0x0/0x20 lib/smp_processor_id.c:57
Code: e8 65 32 08 f6 e8 f0 3d f4 ff 90 65 ff 0d a8 bc 44 08 e9 40 ff ff ff 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 c7 c6 80 36 16 8c 48 c7 c7 c0 36 16 8c e9 f9 fe ff
RSP: 0018:ffffc900000f7600 EFLAGS: 00000282
RAX: 0000000000000001 RBX: 0000000000000001 RCX: 00000000fcfc4e06
RDX: ffffffff816ab56d RSI: ffffffff8de29fdd RDI: ffffffff8c163700
RBP: ffffc900000f76d8 R08: 55f3af06ad7305c1 R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000000000 R12: ffffffff81a676b0
R13: ffffc900000f7690 R14: 0000000000000000 R15: ffff88801e2a9e00
FS: 0000000000000000(0000) GS:ffff8881246ba000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5184778990 CR3: 0000000034e4e000 CR4: 00000000003526f0
Call Trace:
rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
rcu_is_watching+0x12/0xc0 kernel/rcu/tree.c:751
rcu_read_lock include/linux/rcupdate.h:842 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0xa3b/0x20a0 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
save_stack+0x160/0x1f0 mm/page_owner.c:156
__reset_page_owner+0x84/0x1a0 mm/page_owner.c:308
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1395 [inline]
__free_frozen_pages+0x7d5/0x10f0 mm/page_alloc.c:2895
kasan_depopulate_vmalloc_pte+0x5b/0x80 mm/kasan/shadow.c:495
apply_to_pte_range mm/memory.c:3015 [inline]
apply_to_pmd_range mm/memory.c:3059 [inline]
apply_to_pud_range mm/memory.c:3095 [inline]
apply_to_p4d_range mm/memory.c:3131 [inline]
__apply_to_page_range+0xabe/0x13f0 mm/memory.c:3167
kasan_release_vmalloc+0xd1/0xe0 mm/kasan/shadow.c:616
kasan_release_vmalloc_node mm/vmalloc.c:2249 [inline]
purge_vmap_node+0x1c4/0xa30 mm/vmalloc.c:2266
__purge_vmap_area_lazy+0xa06/0xc60 mm/vmalloc.c:2356
drain_vmap_area_work+0x27/0x40 mm/vmalloc.c:2390
process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3236
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x56d/0x730 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245