rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 0-....: (1 GPs behind) idle=01fc/1/0x4000000000000000 softirq=17047/17048 fqs=1501
rcu: hardirqs softirqs csw/system
rcu: number: 1336832 0 0
rcu: cputime: 12039 34823 39 ==> 46900(ms)
rcu: (t=10503 jiffies g=16689 q=3876 ncpus=2)
rcu: rcu_preempt kthread timer wakeup didn't happen for 1006 jiffies! g16689 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=1 timer-softirq=8744
rcu: rcu_preempt kthread starved for 1009 jiffies! g16689 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:26984 pid:17 ppid:2 flags:0x00004000
Call Trace:
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
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: 5750 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:pv_native_safe_halt+0xf/0x10 arch/x86/kernel/paravirt.c:148
Code: d7 22 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 83 e1 43 00 fb f4 66 0f 1f 00 55 41 57 41 56 41 54 53 50 8b 2f eb 2e 41 89 de 80
RSP: 0018:ffffc9000449f6d8 EFLAGS: 000002d3
RAX: ffffffff813aa578 RBX: 0000000000000003 RCX: ffff88807d78bc00
RDX: 0000000000000000 RSI: ffffffff8acac900 RDI: ffffffff8b1c81e0
RBP: ffffc9000449f7b0 R08: ffffffff911bf5c7 R09: 1ffffffff2237eb8
R10: dffffc0000000000 R11: fffffbfff2237eb9 R12: dffffc0000000000
R13: 0000000000000200 R14: 0000000000000003 R15: 1ffff92000893ee0
FS: 0000555580b3b500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055cb3b92da68 CR3: 000000002e53d000 CR4: 00000000003506e0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
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:2603
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: 0033:0x7f773a757197
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:00007ffee5d837a0 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000555580b3b500 RCX: 00007f773a757197
RDX: 00000000000013f0 RSI: 0000555580b5d94c RDI: 0000000000000003
RBP: 00007ffee5d83ca0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00000000000000ac
R13: 000000000000149c R14: 00007ffee5d83890 R15: 0000555580b5d8a0
CPU: 0 PID: 7282 Comm: syz.0.372 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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:ffffc90000005e00 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 51967c0740c4ea00
RDX: 0000000000000000 RSI: ffffffff8acada80 RDI: ffffffff8b1c81e0
RBP: ffffc90000005f10 R08: dffffc0000000000 R09: 1ffffffff2237ea0
R10: dffffc0000000000 R11: fffffbfff2237ea1 R12: 1ffff92000000bcc
R13: ffffffff8d131fa0 R14: 0000000000000246 R15: dffffc0000000000
FS: 00007f791fa636c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000100000000 CR3: 0000000063751000 CR4: 00000000003506f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
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+0x161/0x1410 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+0x179c/0x36b0 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+0x1cbd/0x32f0 net/ipv4/tcp_output.c:1422
tcp_ack_snd_check net/ipv4/tcp_input.c:5728 [inline]
tcp_rcv_established+0xb06/0x1d20 net/ipv4/tcp_input.c:6174
tcp_v4_do_rcv+0x4ed/0xb80 net/ipv4/tcp_ipv4.c:1734
tcp_v4_rcv+0x23bf/0x2af0 net/ipv4/tcp_ipv4.c:2166
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:5664 [inline]
__netif_receive_skb_list_core+0x583/0x750 net/core/dev.c:5712
__netif_receive_skb_list net/core/dev.c:5764 [inline]
netif_receive_skb_list_internal+0x943/0xca0 net/core/dev.c:5855
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:6625
napi_poll net/core/dev.c:6692 [inline]
net_rx_action+0x616/0xc40 net/core/dev.c:6828
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
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:schedule_debug kernel/sched/core.c:5938 [inline]
RIP: 0010:__schedule+0x13f/0x45a0 kernel/sched/core.c:6591
Code: 30 48 8d 58 20 48 89 d8 48 c1 e8 03 42 80 3c 30 00 74 08 48 89 df e8 90 e4 52 f7 48 8b 1b 48 89 d8 48 c1 e8 03 42 80 3c 30 00 <74> 08 48 89 df e8 77 e4 52 f7 48 81 3b 9d 6e ac 57 0f 85 7d 16 00
RSP: 0018:ffffc9000ce2f840 EFLAGS: 00000246
RAX: 1ffff920019c5000 RBX: ffffc9000ce28000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffc9000ce2f9e0
RBP: ffffc9000ce2fa50 R08: ffffc9000ce2f9df R09: 0000000000000000
R10: ffffc9000ce2f9d0 R11: fffff520019c5f3c R12: 1ffff920019c5f28
R13: ffff8880b8e00000 R14: dffffc0000000000 R15: 0000000000000001
preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6867
preempt_schedule+0xc0/0xd0 kernel/sched/core.c:6891
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: 0033:0x7f791eb9bf79
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:00007f791fa630e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f791ee15fa8 RCX: 00007f791eb9bf79
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f791ee15fac
RBP: 00007f791ee15fa0 R08: 0000000000745a24 R09: 0000000000000000
R10: 000000000000000a R11: 0000000000000246 R12: 0000000000000000
R13: 00007f791ee16038 R14: 00007fff48c2bee0 R15: 00007fff48c2bfc8