rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (1 GPs behind) idle=86fc/1/0x4000000000000000 softirq=21872/21873 fqs=9
rcu: 	(t=10502 jiffies g=24185 q=236 ncpus=2)
rcu: rcu_preempt kthread starved for 10485 jiffies! g24185 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:27240 pid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0x15ae/0x4660 kernel/sched/core.c:6700
 schedule+0xbd/0x170 kernel/sched/core.c:6774
 schedule_timeout+0x188/0x2d0 kernel/time/timer.c:2168
 rcu_gp_fqs_loop+0x30d/0x1590 kernel/rcu/tree.c:1667
 rcu_gp_kthread+0x9d/0x3b0 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
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 8452 Comm: syz.3.781 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/25/2026
RIP: 0010:pv_native_safe_halt+0xf/0x10 arch/x86/kernel/paravirt.c:148
Code: 4c 1d 02 c3 cc cc cc cc cc cc cc f3 0f 1e fa 0f 0b 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 66 90 0f 00 2d 43 77 3c 00 fb f4 <c3> 66 0f 1f 00 55 41 57 41 56 41 54 53 50 8b 2f eb 2c 89 cb 80 f9
RSP: 0018:ffffc900001f08b8 EFLAGS: 00000246
RAX: ffffffff813a9538 RBX: 0000000000000003 RCX: ffff88802c10da00
RDX: 0000000000000100 RSI: ffffffff8acacb60 RDI: ffffffff8b1cfa20
RBP: ffffc900001f0990 R08: ffffffff911e75c7 R09: 1ffffffff223ceb8
R10: dffffc0000000000 R11: fffffbfff223ceb9 R12: dffffc0000000000
R13: 0000000000000200 R14: 0000000000000003 R15: 1ffff9200003e11c
FS:  0000555588cba500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f974a627dac CR3: 000000002f997000 CR4: 00000000003506e0
DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000200000000300
DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 arch_safe_halt arch/x86/include/asm/paravirt.h:108 [inline]
 kvm_wait+0x23d/0x2a0 arch/x86/kernel/kvm.c:1058
 pv_wait arch/x86/include/asm/paravirt.h:598 [inline]
 pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline]
 __pv_queued_spin_lock_slowpath+0x613/0x9c0 kernel/locking/qspinlock.c:511
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:586 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
 do_raw_spin_lock+0x23e/0x2b0 kernel/locking/spinlock_debug.c:115
 spin_lock include/linux/spinlock.h:351 [inline]
 tcp_write_timer+0x2d/0x280 net/ipv4/tcp_timer.c:707
 call_timer_fn+0x189/0x540 kernel/time/timer.c:1701
 expire_timers kernel/time/timer.c:1752 [inline]
 __run_timers+0x570/0x810 kernel/time/timer.c:2023
 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2036
 handle_softirqs+0x27d/0x820 kernel/softirq.c:578
 __do_softirq kernel/softirq.c:612 [inline]
 invoke_softirq kernel/softirq.c:452 [inline]
 __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661
 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:pv_native_safe_halt+0xf/0x10 arch/x86/kernel/paravirt.c:148
Code: 4c 1d 02 c3 cc cc cc cc cc cc cc f3 0f 1e fa 0f 0b 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 66 90 0f 00 2d 43 77 3c 00 fb f4 <c3> 66 0f 1f 00 55 41 57 41 56 41 54 53 50 8b 2f eb 2c 89 cb 80 f9
RSP: 0018:ffffc9000b8e7878 EFLAGS: 000002d3
RAX: ffffffff813a9538 RBX: 0000000000000003 RCX: ffff88802c10da00
RDX: 0000000000000000 RSI: ffffffff8acacb60 RDI: ffffffff8b1cfa20
RBP: ffffc9000b8e7950 R08: ffffffff911e75ff R09: 1ffffffff223cebf
R10: dffffc0000000000 R11: fffffbfff223cec0 R12: dffffc0000000000
R13: 0000000000000200 R14: 0000000000000003 R15: 1ffff9200171cf14
 arch_safe_halt arch/x86/include/asm/paravirt.h:108 [inline]
 kvm_wait+0x23d/0x2a0 arch/x86/kernel/kvm.c:1058
 pv_wait arch/x86/include/asm/paravirt.h:598 [inline]
 pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline]
 __pv_queued_spin_lock_slowpath+0x613/0x9c0 kernel/locking/qspinlock.c:511
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:586 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
 do_raw_spin_lock+0x23e/0x2b0 kernel/locking/spinlock_debug.c:115
 spin_lock include/linux/spinlock.h:351 [inline]
 futex_unqueue+0x4e/0xf0 kernel/futex/core.c:597
 futex_wait+0x1f1/0x5c0 kernel/futex/waitwake.c:660
 do_futex+0x2ff/0x3e0 kernel/futex/syscalls.c:134
 __do_sys_futex kernel/futex/syscalls.c:211 [inline]
 __se_sys_futex+0x3a9/0x440 kernel/futex/syscalls.c:192
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7ffab199de99
Code: 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 01 48
RSP: 002b:00007ffc5ca89c88 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 000000000002f7b0 RCX: 00007ffab199de99
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007ffab1c25fac
RBP: 0000000000000032 R08: 0000000000745a46 R09: 0000000000000000
R10: 00007ffc5ca89d90 R11: 0000000000000246 R12: 00007ffc5ca89db0
R13: 00007ffab1c25fac R14: 000000000002f7e2 R15: 00007ffc5ca89d90
 </TASK>
CPU: 0 PID: 8453 Comm: syz.3.781 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/25/2026
RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:55 [inline]
RIP: 0010:unwind_next_frame+0x1c8a/0x2990 arch/x86/kernel/unwind_orc.c:665
Code: f5 0f 85 9e 00 00 00 48 8b 44 24 68 42 80 3c 38 00 74 08 48 89 df e8 05 1d a4 00 4d 8b 75 38 49 8d 7d 08 48 89 f8 48 c1 e8 03 <42> 80 3c 38 00 74 05 e8 ea 1c a4 00 49 8b 5d 08 4d 8d 7d 10 4c 89
RSP: 0018:ffffc90000005f38 EFLAGS: 00000a02
RAX: 1ffff92000000c02 RBX: ffffc90000006040 RCX: 0000000000000100
RDX: ffff88807dd6bc00 RSI: 0000000000000002 RDI: ffffc90000006010
RBP: 0000000000000002 R08: ffff88807dd6bc00 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000000100 R12: ffffc90000006150
R13: ffffc90000006008 R14: ffffc90000006388 R15: dffffc0000000000
FS:  00007ffab27fc6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000100000000 CR3: 000000002f997000 CR4: 00000000003506f0
DR0: 0000000000000008 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4e/0x70 mm/kasan/common.c:53
 kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522
 ____kasan_slab_free+0x126/0x1f0 mm/kasan/common.c:237
 kasan_slab_free include/linux/kasan.h:164 [inline]
 slab_free_hook mm/slub.c:1811 [inline]
 slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837
 slab_free mm/slub.c:3830 [inline]
 __kmem_cache_free+0xba/0x1f0 mm/slub.c:3843
 skb_kfree_head net/core/skbuff.c:946 [inline]
 skb_free_head net/core/skbuff.c:958 [inline]
 skb_release_data+0x609/0x7f0 net/core/skbuff.c:988
 skb_release_all net/core/skbuff.c:1054 [inline]
 __kfree_skb net/core/skbuff.c:1068 [inline]
 kfree_skb_reason+0x10e/0x170 net/core/skbuff.c:1104
 dev_kfree_skb_any_reason+0x120/0x130 net/core/dev.c:3241
 free_old_xmit_skbs+0x11a/0x3b0 drivers/net/virtio_net.c:780
 start_xmit+0x16d/0x1470 drivers/net/virtio_net.c:2420
 __netdev_start_xmit include/linux/netdevice.h:4943 [inline]
 netdev_start_xmit include/linux/netdevice.h:4957 [inline]
 xmit_one net/core/dev.c:3644 [inline]
 dev_hard_start_xmit+0x269/0x790 net/core/dev.c:3660
 sch_direct_xmit+0x251/0x4a0 net/sched/sch_generic.c:345
 __dev_xmit_skb net/core/dev.c:3881 [inline]
 __dev_queue_xmit+0x162a/0x3630 net/core/dev.c:4416
 neigh_output include/net/neighbour.h:543 [inline]
 ip_finish_output2+0xd97/0x1260 net/ipv4/ip_output.c:235
 NF_HOOK_COND include/linux/netfilter.h:293 [inline]
 ip_output+0x2a5/0x3a0 net/ipv4/ip_output.c:436
 dst_output include/net/dst.h:467 [inline]
 ip_local_out net/ipv4/ip_output.c:129 [inline]
 __ip_queue_xmit+0x1056/0x1960 net/ipv4/ip_output.c:540
 __tcp_transmit_skb+0x1dd6/0x3470 net/ipv4/tcp_output.c:1427
 tcp_ack_snd_check net/ipv4/tcp_input.c:5738 [inline]
 tcp_rcv_established+0xb22/0x1d70 net/ipv4/tcp_input.c:6184
 tcp_v4_do_rcv+0x6d3/0xba0 net/ipv4/tcp_ipv4.c:1735
 tcp_v4_rcv+0x2358/0x2a60 net/ipv4/tcp_ipv4.c:2167
 ip_protocol_deliver_rcu+0x20a/0x3f0 net/ipv4/ip_input.c:205
 ip_local_deliver_finish+0x2c3/0x510 net/ipv4/ip_input.c:233
 NF_HOOK+0x32d/0x3b0 include/linux/netfilter.h:304
 dst_input include/net/dst.h:477 [inline]
 ip_sublist_rcv_finish net/ipv4/ip_input.c:580 [inline]
 ip_list_rcv_finish net/ipv4/ip_input.c:631 [inline]
 ip_sublist_rcv+0xa36/0xd60 net/ipv4/ip_input.c:639
 ip_list_rcv+0x3ed/0x440 net/ipv4/ip_input.c:674
 __netif_receive_skb_list_ptype net/core/dev.c:5689 [inline]
 __netif_receive_skb_list_core+0x582/0x770 net/core/dev.c:5737
 __netif_receive_skb_list net/core/dev.c:5789 [inline]
 netif_receive_skb_list_internal+0x943/0xca0 net/core/dev.c:5880
 gro_normal_list include/net/gro.h:451 [inline]
 napi_complete_done+0x329/0x820 net/core/dev.c:6220
 virtqueue_napi_complete drivers/net/virtio_net.c:450 [inline]
 virtnet_poll+0xaa0/0x11e0 drivers/net/virtio_net.c:2236
 __napi_poll+0xbb/0x460 net/core/dev.c:6650
 napi_poll net/core/dev.c:6717 [inline]
 net_rx_action+0x65f/0xcc0 net/core/dev.c:6853
 handle_softirqs+0x27d/0x820 kernel/softirq.c:578
 __do_softirq kernel/softirq.c:612 [inline]
 invoke_softirq kernel/softirq.c:452 [inline]
 __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661
 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:lock_is_held_type+0x13e/0x190 kernel/locking/lockdep.c:5830
Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c5 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc9000b36fb68 EFLAGS: 00000206
RAX: 1068b30e58d83700 RBX: ffff88807dd6bc00 RCX: 1068b30e58d83700
RDX: ffff88807dd6bc00 RSI: ffffffff8acadce0 RDI: ffffffff8b1cfa20
RBP: 0000000000000001 R08: ffff88802c10da2b R09: 1ffff11005821b45
R10: dffffc0000000000 R11: ffffed1005821b46 R12: 0000000000000000
R13: 0000000000000246 R14: ffffc90000a37420 R15: ffff88807dd6c6e0
 lock_is_held include/linux/lockdep.h:288 [inline]
 __futex_unqueue+0xad/0x150 kernel/futex/core.c:515
 futex_wake_mark+0xec/0x150 kernel/futex/waitwake.c:123
 futex_wake+0x32f/0x4f0 kernel/futex/waitwake.c:177
 do_futex+0x35d/0x3e0 kernel/futex/syscalls.c:139
 __do_sys_futex kernel/futex/syscalls.c:211 [inline]
 __se_sys_futex+0x3a9/0x440 kernel/futex/syscalls.c:192
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7ffab199de99
Code: 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 01 48
RSP: 002b:00007ffab27fc0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007ffab1c25fa8 RCX: 00007ffab199de99
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007ffab1c25fac
RBP: 00007ffab1c25fa0 R08: 0000000000745a46 R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffab1c26038 R14: 00007ffc5ca89a40 R15: 00007ffc5ca89b28
 </TASK>