INFO: task syz.5.1402:11212 blocked for more than 143 seconds.
Not tainted 6.15.0-rc5-syzkaller-00204-g0e1329d4045c #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.1402 state:D stack:26696 pid:11212 tgid:11211 ppid:10813 task_flags:0x400140 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x116f/0x5de0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6860
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
__mutex_lock_common kernel/locking/mutex.c:678 [inline]
__mutex_lock+0x6c7/0xb90 kernel/locking/mutex.c:746
nfsd_nl_listener_set_doit+0xdd/0x1a40 fs/nfsd/nfsctl.c:1923
genl_family_rcv_msg_doit+0x206/0x2f0 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+0x16a/0x440 net/netlink/af_netlink.c:2534
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
netlink_unicast+0x53a/0x7f0 net/netlink/af_netlink.c:1339
netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1883
sock_sendmsg_nosec net/socket.c:712 [inline]
__sock_sendmsg net/socket.c:727 [inline]
____sys_sendmsg+0xa95/0xc70 net/socket.c:2566
___sys_sendmsg+0x134/0x1d0 net/socket.c:2620
__sys_sendmsg+0x16d/0x220 net/socket.c:2652
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f77c378e969
RSP: 002b:00007f77c454f038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f77c39b5fa0 RCX: 00007f77c378e969
RDX: 0000000000000000 RSI: 0000200000000040 RDI: 0000000000000004
RBP: 00007f77c3810ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f77c39b5fa0 R15: 00007ffd5ab8ab08
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e3bf5c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6764
2 locks held by getty/5568:
#0: ffff88814d21f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900036cb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
5 locks held by kworker/u8:10/6540:
2 locks held by syz.4.1275/10603:
#0: ffffffff901c6e90 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e7cd028 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xdd/0x1a40 fs/nfsd/nfsctl.c:1923
2 locks held by syz.5.1402/11212:
#0: ffffffff901c6e90 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e7cd028 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xdd/0x1a40 fs/nfsd/nfsctl.c:1923
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc5-syzkaller-00204-g0e1329d4045c #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline]
watchdog+0xf70/0x12c0 kernel/hung_task.c:437
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
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: 6540 Comm: kworker/u8:10 Not tainted 6.15.0-rc5-syzkaller-00204-g0e1329d4045c #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_unbound macvlan_process_broadcast
RIP: 0010:__lock_acquire+0x173/0x1ba0 kernel/locking/lockdep.c:5172
Code: 25 00 e0 09 d0 66 89 43 20 48 8b 84 24 b0 00 00 00 48 89 43 08 41 8b 8e d4 0a 00 00 31 c0 65 8b 15 ca 4b 0c 12 85 c9 44 89 e9 <44> 8b ac 24 c8 00 00 00 0f 95 c0 85 d2 0f 95 c2 41 c1 e2 0f c1 e1
RSP: 0018:ffffc90000a084d0 EFLAGS: 00000002
RAX: 0000000000000000 RBX: ffff888030708b90 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffff888030708b68 RDI: ffff888030708b90
RBP: ffff888030708af0 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: ffffffff8e3bf5c0 R12: 0000000000000000
R13: 0000000000000002 R14: ffff888030708000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888124ae1000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055f8df963620 CR3: 000000003456c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire kernel/locking/lockdep.c:5866 [inline]
lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5823
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0xd1/0x20a0 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
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
unpoison_slab_object mm/kasan/common.c:319 [inline]
__kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:345
kasan_slab_alloc include/linux/kasan.h:250 [inline]
slab_post_alloc_hook mm/slub.c:4147 [inline]
slab_alloc_node mm/slub.c:4196 [inline]
kmem_cache_alloc_node_noprof+0x1d5/0x3b0 mm/slub.c:4248
kmalloc_reserve+0x18b/0x2c0 net/core/skbuff.c:577
__alloc_skb+0x166/0x380 net/core/skbuff.c:668
skb_copy+0x1c9/0x3a0 net/core/skbuff.c:2131
x25_lapb_receive_frame+0x93/0xf70 net/x25/x25_dev.c:103
__netif_receive_skb_one_core+0x1af/0x1e0 net/core/dev.c:5887
netif_receive_skb_core+0x5a/0x1a0 net/core/dev.c:5912
lapbeth_napi_poll+0x47/0xd0 drivers/net/wan/lapbether.c:100
__napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:7324
napi_poll net/core/dev.c:7388 [inline]
net_rx_action+0xa97/0x1010 net/core/dev.c:7510
handle_softirqs+0x216/0x8e0 kernel/softirq.c:579
do_softirq kernel/softirq.c:480 [inline]
do_softirq+0xb2/0xf0 kernel/softirq.c:467
__local_bh_enable_ip+0x100/0x120 kernel/softirq.c:407
local_bh_enable include/linux/bottom_half.h:33 [inline]
netif_rx net/core/dev.c:5457 [inline]
netif_rx+0x93/0xb0 net/core/dev.c:5446
macvlan_broadcast+0x37d/0x680 drivers/net/macvlan.c:291
macvlan_multicast_rx drivers/net/macvlan.c:303 [inline]
macvlan_multicast_rx+0xd6/0x100 drivers/net/macvlan.c:297
macvlan_process_broadcast+0x224/0x690 drivers/net/macvlan.c:339
process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
lapbether: lapb_data_request error - 4
lapbether: lapb_data_request error - 4
lapbether: lapb_data_request error - 4
lapbether: lapb_data_request error - 4
lapbether: lapb_data_request error - 4
lapbether: lapb_data_request error - 4
lapbether: lapb_data_request error - 4
lapbether: lapb_data_request error - 4
lapbether: lapb_data_request error - 4
lapbether: lapb_data_request error - 4
lapbether: lapb_data_request error - 4