rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P8313/2:b..l
(detected by 1, t=10502 jiffies, g=43225, q=8335 ncpus=2)
task:syz.7.1090 state:R running task stack:25712 pid:8313 ppid:5957 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6731
preempt_schedule+0xbc/0xd0 kernel/sched/core.c:6755
preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
__local_bh_enable_ip+0x147/0x1c0 kernel/softirq.c:428
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_read_unlock_bh include/linux/rcupdate.h:861 [inline]
__dev_queue_xmit+0x1cd2/0x37c0 net/core/dev.c:4411
dev_queue_xmit include/linux/netdevice.h:3051 [inline]
neigh_hh_output include/net/neighbour.h:529 [inline]
neigh_output include/net/neighbour.h:543 [inline]
ip_finish_output2+0xbe8/0x11b0 net/ipv4/ip_output.c:228
NF_HOOK_COND include/linux/netfilter.h:291 [inline]
ip_output+0x2df/0x410 net/ipv4/ip_output.c:434
dst_output include/net/dst.h:453 [inline]
ip_local_out net/ipv4/ip_output.c:126 [inline]
ip_send_skb+0x129/0x1c0 net/ipv4/ip_output.c:1608
raw_sendmsg+0x153d/0x1b20 net/ipv4/raw.c:653
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
____sys_sendmsg+0x5be/0x970 net/socket.c:2518
___sys_sendmsg+0x2a2/0x360 net/socket.c:2572
__sys_sendmmsg+0x2c3/0x510 net/socket.c:2658
__do_sys_sendmmsg net/socket.c:2687 [inline]
__se_sys_sendmmsg net/socket.c:2684 [inline]
__x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2684
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f533bf9ce59
RSP: 002b:00007f533ce09028 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f533c215fa0 RCX: 00007f533bf9ce59
RDX: 0000000004000095 RSI: 0000200000005240 RDI: 0000000000000004
RBP: 00007f533c032d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f533c216038 R14: 00007f533c215fa0 R15: 00007ffc7f63bd08
rcu: rcu_preempt kthread starved for 10539 jiffies! g43225 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:27504 pid:16 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
schedule+0xb9/0x180 kernel/sched/core.c:6638
schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2168
rcu_gp_fqs_loop+0x303/0x1340 kernel/rcu/tree.c:1706
rcu_gp_kthread+0x99/0x3b0 kernel/rcu/tree.c:1905
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
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: 8324 Comm: syz.3.1093 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:rb_next+0x5b/0xd0 lib/rbtree.c:503
Code: 89 f0 5b 41 5e 41 5f c3 4c 8d 73 08 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 cd 35 b5 f7 49 8b 06 48 85 c0 75 0a 30 48 8b 03 48 85 c0 74 cb 49 89 c6 48 8d 58 10 48 89 d8 48 c1
RSP: 0018:ffffc90000007ce8 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff888059c8bb20 RCX: ffff88801b343b80
RDX: 0000000000010000 RSI: ffff888059c8bb20 RDI: ffff888059c8bb20
RBP: 1ffff1100b391764 R08: ffffffff96eb495b R09: 1ffffffff2dd692b
R10: dffffc0000000000 R11: fffffbfff2dd692c R12: ffff8880b8e2a698
R13: dffffc0000000000 R14: ffff888059c8bb28 R15: dffffc0000000000
FS: 00007ff99f1406c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000006b000 CR3: 00000000731f6000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
rb_erase_cached include/linux/rbtree.h:124 [inline]
timerqueue_del+0x86/0x100 lib/timerqueue.c:57
__remove_hrtimer kernel/time/hrtimer.c:1138 [inline]
__run_hrtimer kernel/time/hrtimer.c:1727 [inline]
__hrtimer_run_queues+0x389/0xd50 kernel/time/hrtimer.c:1811
hrtimer_interrupt+0x3c5/0x9c0 kernel/time/hrtimer.c:1873
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
__sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: 00 00 00 66 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 5e b1 2c f7 48 89 df e8 a6 79 2d f7 e8 81 d0 50 f7 fb bf 01 00 00 00 f6 dd 20 f7 65 8b 05 f7 4f ca 75 85 c0 74 02 5b c3 e8 44 64 c8
RSP: 0018:ffffc9000412fb98 EFLAGS: 00000282
RAX: b0566150355b0e00 RBX: ffff8880542c2500 RCX: b0566150355b0e00
RDX: dffffc0000000000 RSI: ffffffff8a8c19a0 RDI: 0000000000000001
RBP: ffff8880542c2998 R08: ffff8880542c2503 R09: 1ffff1100a8584a0
R10: dffffc0000000000 R11: ffffed100a8584a1 R12: 1ffff1100a858533
R13: 0000000000000021 R14: dffffc0000000000 R15: 0000000000000000
spin_unlock_irq include/linux/spinlock.h:401 [inline]
get_signal+0x1163/0x1350 kernel/signal.c:2874
arch_do_signal_or_restart+0xc4/0x1350 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7ff99e19ce57
Code: 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 e8 ff ff ff f7 d8 64 89
RSP: 002b:00007ff99f1400e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007ff99e415fa8 RCX: 00007ff99e19ce59
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007ff99e415fa8
RBP: 00007ff99e415fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff99e416038 R14: 00007fff3c9e34d0 R15: 00007fff3c9e35b8