rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-....: (10283 ticks this GP) idle=dafc/1/0x4000000000000000 softirq=24403/24403 fqs=1174
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number:  1499734          0            0
rcu: 	cputime:    14507      37081           39   ==> 51620(ms)
rcu: 	(t=10504 jiffies g=30737 q=1752 ncpus=2)
rcu: rcu_preempt kthread timer wakeup didn't happen for 365 jiffies! g30737 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=19988
rcu: rcu_preempt kthread starved for 368 jiffies! g30737 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:26824 pid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0x1553/0x45a0 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+0x313/0x1590 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 5757 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:pv_native_safe_halt+0xf/0x10 arch/x86/kernel/paravirt.c:148
Code: 4e 21 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 03 19 42 00 fb f4 <c3> 66 0f 1f 00 55 41 57 41 56 41 54 53 50 8b 2f eb 2e 41 89 de 80
RSP: 0018:ffffc90003c776d8 EFLAGS: 000002d3
RAX: ffffffff813aa578 RBX: 0000000000000003 RCX: ffff88802eee9e00
RDX: 0000000000000000 RSI: ffffffff8acac9e0 RDI: ffffffff8b1c8de0
RBP: ffffc90003c777b0 R08: ffffffff911c45c7 R09: 1ffffffff22388b8
R10: dffffc0000000000 R11: fffffbfff22388b9 R12: dffffc0000000000
R13: 0000000000000200 R14: 0000000000000003 R15: 1ffff9200078eee0
FS:  0000555586bea500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4acc8c592a CR3: 0000000074816000 CR4: 00000000003506f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 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+0x61a/0x9d0 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/0x2c0 kernel/locking/spinlock_debug.c:115
 spin_lock_bh include/linux/spinlock.h:356 [inline]
 lock_sock_nested+0x6a/0x100 net/core/sock.c:3538
 lock_sock include/net/sock.h:1780 [inline]
 tcp_recvmsg+0x214/0x860 net/ipv4/tcp.c:2607
 inet_recvmsg+0x140/0x1f0 net/ipv4/af_inet.c:882
 sock_recvmsg_nosec net/socket.c:1046 [inline]
 sock_recvmsg net/socket.c:1068 [inline]
 sock_read_iter+0x2d9/0x3e0 net/socket.c:1138
 call_read_iter include/linux/fs.h:2012 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x46a/0x970 fs/read_write.c:470
 ksys_read+0x150/0x260 fs/read_write.c:613
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f4aceb57997
Code: 48 89 fa 4c 89 df e8 a8 56 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007fff4d9a2840 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000555586bea500 RCX: 00007f4aceb57997
RDX: 0000000000000004 RSI: 00007fff4d9a289c RDI: 0000000000000003
RBP: 00007fff4d9a2d40 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000004
R13: 00007fff4d9a289c R14: 00007fff4d9a2930 R15: 0000000000000000
 </TASK>
CPU: 1 PID: 7929 Comm: syz.3.695 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:lock_acquire+0x208/0x420 kernel/locking/lockdep.c:5758
Code: f7 84 24 80 00 00 00 00 02 00 00 43 c6 44 3c 04 f8 0f 85 f0 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 04 3c 00 00 00 00 43 c7 44 3c 08 00 00 00 00 65 48 8b 04 25
RSP: 0018:ffffc900001eee00 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 5cf017b7fcf3e200
RDX: 0000000000000000 RSI: ffffffff8acadb60 RDI: ffffffff8b1c8de0
RBP: ffffc900001eef10 R08: dffffc0000000000 R09: 1ffffffff22388a0
R10: dffffc0000000000 R11: fffffbfff22388a1 R12: 1ffff9200003ddcc
R13: ffffffff8d1320a0 R14: 0000000000000246 R15: dffffc0000000000
FS:  00007f95751c26c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000100000000 CR3: 000000005dc14000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000200000000300
DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
 rcu_read_lock include/linux/rcupdate.h:786 [inline]
 is_bpf_text_address+0x47/0x2a0 kernel/bpf/core.c:741
 kernel_text_address+0xa0/0xd0 kernel/extable.c:125
 __kernel_text_address+0xd/0x30 kernel/extable.c:79
 unwind_get_return_address+0x5d/0xc0 arch/x86/kernel/unwind_orc.c:369
 arch_stack_walk+0x11d/0x190 arch/x86/kernel/stacktrace.c:26
 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+0x2e/0x50 mm/kasan/generic.c:522
 ____kasan_slab_free+0x126/0x1e0 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+0xf8/0x270 mm/slub.c:3852
 dev_kfree_skb_any_reason+0x120/0x130 net/core/dev.c:3241
 free_old_xmit_skbs+0x11a/0x3d0 drivers/net/virtio_net.c:780
 start_xmit+0x168/0x14a0 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:3632 [inline]
 dev_hard_start_xmit+0x246/0x740 net/core/dev.c:3648
 sch_direct_xmit+0x25e/0x4c0 net/sched/sch_generic.c:345
 __dev_xmit_skb net/core/dev.c:3869 [inline]
 __dev_queue_xmit+0x165d/0x3660 net/core/dev.c:4404
 dev_queue_xmit include/linux/netdevice.h:3113 [inline]
 neigh_hh_output include/net/neighbour.h:527 [inline]
 neigh_output include/net/neighbour.h:541 [inline]
 ip_finish_output2+0xcec/0x11e0 net/ipv4/ip_output.c:235
 NF_HOOK_COND include/linux/netfilter.h:293 [inline]
 ip_output+0x2a1/0x3b0 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+0x1049/0x1950 net/ipv4/ip_output.c:540
 __tcp_transmit_skb+0x1d6b/0x33f0 net/ipv4/tcp_output.c:1425
 tcp_ack_snd_check net/ipv4/tcp_input.c:5736 [inline]
 tcp_rcv_established+0xb06/0x1d20 net/ipv4/tcp_input.c:6182
 tcp_v4_do_rcv+0x4ed/0xb80 net/ipv4/tcp_ipv4.c:1735
 tcp_v4_rcv+0x23bf/0x2af0 net/ipv4/tcp_ipv4.c:2167
 ip_protocol_deliver_rcu+0x20e/0x3f0 net/ipv4/ip_input.c:205
 ip_local_deliver_finish+0x2ca/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+0xa4c/0xd70 net/ipv4/ip_input.c:639
 ip_list_rcv+0x3f2/0x440 net/ipv4/ip_input.c:674
 __netif_receive_skb_list_ptype net/core/dev.c:5677 [inline]
 __netif_receive_skb_list_core+0x583/0x750 net/core/dev.c:5725
 __netif_receive_skb_list net/core/dev.c:5777 [inline]
 netif_receive_skb_list_internal+0x943/0xca0 net/core/dev.c:5868
 gro_normal_list include/net/gro.h:451 [inline]
 gro_normal_one include/net/gro.h:464 [inline]
 napi_skb_finish net/core/gro.c:575 [inline]
 napi_gro_receive+0x565/0xb00 net/core/gro.c:605
 receive_buf+0x2203/0x3820 drivers/net/virtio_net.c:1870
 virtnet_receive drivers/net/virtio_net.c:2155 [inline]
 virtnet_poll+0x5dd/0x1280 drivers/net/virtio_net.c:2229
 __napi_poll+0xc0/0x460 net/core/dev.c:6638
 napi_poll net/core/dev.c:6705 [inline]
 net_rx_action+0x616/0xc40 net/core/dev.c:6841
 handle_softirqs+0x280/0x820 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:preempt_schedule_irq+0xba/0x150 kernel/sched/core.c:7010
Code: 00 00 43 c6 44 37 04 f8 74 0b 0f 0b 48 f7 03 08 00 00 00 74 6f bf 01 00 00 00 e8 a1 1b ce f6 e8 cc 28 ff f6 fb bf 01 00 00 00 <e8> f1 b4 ff ff 43 c6 44 37 08 00 48 c7 44 24 40 00 00 00 00 9c 8f
RSP: 0018:ffffc9000c8cf9a0 EFLAGS: 00000286
RAX: 5cf017b7fcf3e200 RBX: 0000000000000000 RCX: 5cf017b7fcf3e200
RDX: dffffc0000000000 RSI: ffffffff8acac9e0 RDI: 0000000000000001
RBP: ffffc9000c8cfa40 R08: ffffffff8e8b0c2f R09: 1ffffffff1d16185
R10: dffffc0000000000 R11: fffffbfff1d16186 R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92001919f34
 irqentry_exit+0x67/0x70 kernel/entry/common.c:438
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:preempt_schedule+0x0/0xd0 kernel/sched/core.c:6884
Code: 4c 89 f7 e8 f2 f0 50 f7 eb af 66 0f 1f 00 bf 01 00 00 00 e8 a2 20 ce f6 e8 fd fd ff ff bf 01 00 00 00 e8 f3 1e ce f6 c3 66 90 <f3> 0f 1e fa 55 48 89 e5 41 56 53 48 83 e4 e0 48 83 ec 60 65 48 8b
RSP: 0018:ffffc9000c8cfb00 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: ffffffff8acac9e0 RDI: 00000000ffffffff
RBP: ffffc9000c8cfb50 R08: ffffffff8e8b0c2f R09: 1ffffffff1d16185
R10: dffffc0000000000 R11: fffffbfff1d16186 R12: ffff88802e99da00
R13: ffff8880b8f3cd58 R14: 0000000000000001 R15: 000000000000c749
 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45
 class_preempt_destructor include/linux/preempt.h:478 [inline]
 try_to_wake_up+0x781/0x1190 kernel/sched/core.c:4356
 wake_up_process kernel/sched/core.c:4481 [inline]
 wake_up_q+0xb6/0x100 kernel/sched/core.c:1032
 futex_wake+0x42a/0x4f0 kernel/futex/waitwake.c:184
 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+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f957439c819
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:00007f95751c20e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f9574615fa8 RCX: 00007f957439c819
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f9574615fac
RBP: 00007f9574615fa0 R08: 0000000000745a8c R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9574616038 R14: 00007ffef42ecd70 R15: 00007ffef42ece58
 </TASK>
NMI backtrace for cpu 1
CPU: 1 PID: 7929 Comm: syz.3.695 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:102 [inline]
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:227 [inline]
RIP: 0010:unwind_next_frame+0x4b3/0x2970 arch/x86/kernel/unwind_orc.c:494
Code: 48 c1 e8 3f 48 01 c8 48 83 e0 fe 4d 8d 3c 44 4c 89 f8 48 c1 e8 03 0f b6 04 10 84 c0 75 3e 4d 63 2f 4d 01 fd 4c 89 ef 4c 89 f6 <e8> 68 e7 4b 00 49 8d 47 04 4d 39 f5 4c 0f 46 e0 49 8d 47 fc 48 0f
RSP: 0018:ffffc900001ef430 EFLAGS: 00000087
RAX: 0000000000000000 RBX: ffffffff8f0406dc RCX: 0000000000000006
RDX: dffffc0000000000 RSI: ffffffff8a861d63 RDI: ffffffff8a861d24
RBP: ffffffff8f0406c4 R08: ffff888029373c00 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000000100 R12: ffffffff8f0406c4
R13: ffffffff8a861d24 R14: ffffffff8a861d63 R15: ffffffff8f0406d0
FS:  00007f95751c26c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000100000000 CR3: 000000005dc14000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000200000000300
DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 perf_callchain_kernel+0x42e/0x690 arch/x86/events/core.c:2780
 get_perf_callchain+0x231/0x510 kernel/events/callchain.c:204
 perf_callchain kernel/events/core.c:7742 [inline]
 perf_sample_save_callchain include/linux/perf_event.h:1232 [inline]
 perf_prepare_sample+0x3c7/0x1df0 kernel/events/core.c:7786
 __perf_event_output kernel/events/core.c:7974 [inline]
 perf_event_output_forward+0x187/0x3e0 kernel/events/core.c:7995
 __perf_event_overflow+0x447/0x630 kernel/events/core.c:9720
 perf_swevent_overflow kernel/events/core.c:9803 [inline]
 perf_swevent_event+0x319/0x570 kernel/events/core.c:9854
 perf_tp_event+0x5f9/0x1520 kernel/events/core.c:10381
 perf_trace_run_bpf_submit+0xf4/0x1c0 kernel/events/core.c:10300
 perf_trace_preemptirq_template+0x269/0x330 include/trace/events/preemptirq.h:14
 trace_irq_enable+0xbb/0xe0 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x18/0x40 kernel/trace/trace_preemptirq.c:56
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:kvm_kick_cpu+0x4/0xb0 arch/x86/kernel/kvm.c:1030
Code: ff ff 4c 89 f7 e8 8c b2 a4 00 e9 67 ff ff ff e8 02 7c 4c 00 0f 0b e8 fb 7b 4c 00 0f 0b 66 0f 1f 84 00 00 00 00 00 f3 0f 1e fa <41> 57 41 56 53 89 fb e8 e0 7b 4c 00 bf 08 00 00 00 89 de e8 84 7f
RSP: 0018:ffffc900001eff38 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff88807a519918 RCX: 0000000000000008
RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffff88807a51991b R09: 1ffff1100f4a3323
R10: dffffc0000000000 R11: ffffed100f4a3324 R12: 1ffff11047ffc2b8
R13: dffffc0000000000 R14: ffff8880b8e3ce90 R15: ffff88823ffe15c0
 pv_kick kernel/locking/qspinlock_paravirt.h:543 [inline]
 __pv_queued_spin_unlock_slowpath+0x198/0x2a0 kernel/locking/qspinlock_paravirt.h:543
 __raw_callee_save___pv_queued_spin_unlock_slowpath+0x15/0x30
 .slowpath+0x9/0x1a
 pv_queued_spin_unlock arch/x86/include/asm/paravirt.h:591 [inline]
 queued_spin_unlock arch/x86/include/asm/qspinlock.h:57 [inline]
 do_raw_spin_unlock+0x121/0x230 kernel/locking/spinlock_debug.c:141
 __raw_spin_unlock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_unlock+0x1e/0x40 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 tcp_v4_rcv+0x2483/0x2af0 net/ipv4/tcp_ipv4.c:2172
 ip_protocol_deliver_rcu+0x20e/0x3f0 net/ipv4/ip_input.c:205
 ip_local_deliver_finish+0x2ca/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+0xa4c/0xd70 net/ipv4/ip_input.c:639
 ip_list_rcv+0x3f2/0x440 net/ipv4/ip_input.c:674