rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5785/1:b..l
rcu: (detected by 1, t=10503 jiffies, g=6589, q=498 ncpus=2)
task:syz-executor224 state:R running task stack:21736 pid:5785 ppid:5782 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6866
preempt_schedule+0xab/0xc0 kernel/sched/core.c:6890
preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45
vprintk_emit+0x578/0x600 kernel/printk/printk.c:2342
dev_vprintk_emit+0x338/0x3e0 drivers/base/core.c:4953
dev_printk_emit+0xe1/0x130 drivers/base/core.c:4964
__netdev_printk+0x3bf/0x4a0 net/core/dev.c:11482
netdev_info+0x10b/0x160 net/core/dev.c:11537
nsim_udp_tunnel_set_port+0x297/0x440 drivers/net/netdevsim/udp_tunnels.c:34
udp_tunnel_nic_device_sync_one net/ipv4/udp_tunnel_nic.c:-1 [inline]
udp_tunnel_nic_device_sync_by_port net/ipv4/udp_tunnel_nic.c:246 [inline]
__udp_tunnel_nic_device_sync+0xa70/0x1370 net/ipv4/udp_tunnel_nic.c:289
udp_tunnel_nic_device_sync net/ipv4/udp_tunnel_nic.c:312 [inline]
__udp_tunnel_nic_add_port+0xaf8/0xdb0 net/ipv4/udp_tunnel_nic.c:531
udp_tunnel_nic_add_port include/net/udp_tunnel.h:333 [inline]
udp_tunnel_notify_add_rx_port+0x28e/0x3e0 net/ipv4/udp_tunnel_core.c:127
geneve_socket_create drivers/net/geneve.c:614 [inline]
geneve_sock_add+0x55e/0x910 drivers/net/geneve.c:689
geneve_open+0xd2/0x140 drivers/net/geneve.c:731
__dev_open+0x2bc/0x430 net/core/dev.c:1506
__dev_change_flags+0x20e/0x6a0 net/core/dev.c:8685
dev_change_flags+0x88/0x1a0 net/core/dev.c:8757
do_setlink+0xc74/0x3fb0 net/core/rtnetlink.c:2905
__rtnl_newlink net/core/rtnetlink.c:3703 [inline]
rtnl_newlink+0x175b/0x2020 net/core/rtnetlink.c:3750
rtnetlink_rcv_msg+0x7c7/0xf10 net/core/rtnetlink.c:6475
netlink_rcv_skb+0x216/0x480 net/netlink/af_netlink.c:2545
netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
netlink_unicast+0x751/0x8d0 net/netlink/af_netlink.c:1346
netlink_sendmsg+0x8c1/0xbe0 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
__sys_sendto+0x46a/0x620 net/socket.c:2201
__do_sys_sendto net/socket.c:2213 [inline]
__se_sys_sendto net/socket.c:2209 [inline]
__x64_sys_sendto+0xde/0xf0 net/socket.c:2209
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fcb828b281c
RSP: 002b:00007ffdd00c8810 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fcb8293c420 RCX: 00007fcb828b281c
RDX: 000000000000002c RSI: 00007fcb8293c470 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007ffdd00c8864 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001
R13: 0000000000000000 R14: 00007fcb8293c470 R15: 0000000000000000
rcu: rcu_preempt kthread starved for 6140 jiffies! g6589 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt state:R running task stack:27344 pid:17 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
schedule+0xbd/0x170 kernel/sched/core.c:6773
schedule_timeout+0x160/0x280 kernel/time/timer.c:2167
rcu_gp_fqs_loop+0x302/0x1560 kernel/rcu/tree.c:1667
rcu_gp_kthread+0x99/0x380 kernel/rcu/tree.c:1866
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 5859 Comm: syz-executor224 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:lock_acquire+0x81/0x410 kernel/locking/lockdep.c:5722
Code: 41 48 c7 44 24 68 c6 b6 59 8c 48 c7 44 24 70 a0 00 67 81 4c 8d 64 24 60 49 c1 ec 03 48 b8 f1 f1 f1 f1 00 f2 f2 f2 4b 89 04 3c <66> 43 c7 44 3c 09 f3 f3 43 c6 44 3c 0b f3 0f 1f 44 00 00 65 8b 05
RSP: 0018:ffffc90000007c40 EFLAGS: 00000802
RAX: f2f2f200f1f1f1f1 RBX: 0000000000000000 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8cd49e88
RBP: ffffc90000007d48 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000010000 R12: 1ffff92000000f94
R13: ffffffff8cd49e88 R14: 1ffff92000000fac R15: dffffc0000000000
FS: 00005555757623c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000006b000 CR3: 0000000021031000 CR4: 00000000003506f0
Call Trace:
seqcount_lockdep_reader_access+0xca/0x1c0 include/linux/seqlock.h:102
ktime_get+0x35/0x280 kernel/time/timekeeping.c:846
clockevents_program_event+0xe6/0x310 kernel/time/clockevents.c:326
hrtimer_interrupt+0x5a1/0x9c0 kernel/time/hrtimer.c:1894
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline]
__sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202
Code: 00 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 2a c0 ef f6 48 89 df e8 42 92 f0 f6 e8 4d 31 14 f7 fb bf 01 00 00 00 52 a9 e3 f6 65 8b 05 a3 f7 8b 75 85 c0 74 02 5b c3 e8 80 d9 88
RSP: 0018:ffffc90004c9fc98 EFLAGS: 00000282
RAX: e8f33711edabb100 RBX: ffff8880701eca00 RCX: e8f33711edabb100
RDX: dffffc0000000000 RSI: ffffffff8aaabca0 RDI: 0000000000000001
RBP: ffff8880701ece98 R08: ffffffff8e4a94ef R09: 1ffffffff1c9529d
R10: dffffc0000000000 R11: fffffbfff1c9529e R12: 1ffff1100e03d9d3
R13: 0000000000000021 R14: dffffc0000000000 R15: 0000000000000000
spin_unlock_irq include/linux/spinlock.h:401 [inline]
get_signal+0x11f5/0x1400 kernel/signal.c:2905
arch_do_signal_or_restart+0x96/0x780 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xf6/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fcb828b0e39
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 91 1a 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffdd00c8dc8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007fcb828b0e39
RDX: 000020000006b000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000000 R08: 00007fcb829071fa R09: 00007fcb829071fa
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffdd00c8dec
R13: 00007ffdd00c8e20 R14: 00007ffdd00c8e00 R15: 0000000000000001
sched: RT throttling activated