rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=c7bc/1/0x4000000000000000 softirq=88731/88732 fqs=836
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P18517/1:b..l
rcu: 	(detected by 0, t=10505 jiffies, g=88137, q=151 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 18518 Comm: syz.3.4172 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:check_preemption_disabled+0x40/0x120 lib/smp_processor_id.c:53
Code: 08 65 8b 05 e6 64 42 07 65 8b 0d db 64 42 07 f7 c1 ff ff ff 7f 74 23 65 48 8b 0d bb 64 42 07 48 3b 4c 24 08 0f 85 cc 00 00 00 <48> 83 c4 10 5b 41 5e 41 5f 5d c3 cc cc cc cc cc 48 c7 04 24 00 00
RSP: 0018:ffffc90000a08ae8 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000000 RCX: adf8eefa1f7f8700
RDX: 0000000000000000 RSI: ffffffff8c03da40 RDI: ffffffff8c03da00
RBP: ffffffff84d744fb R08: 0000000000000001 R09: 0000000000000000
R10: ffffc90000a08ca0 R11: fffff52000141196 R12: 0000000000000000
R13: ffffffff99efb650 R14: 0000000000000000 R15: 0000000000000001
FS:  00007f32cc0636c0(0000) GS:ffff888125afc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b33e1dff8 CR3: 00000000227e6000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
 rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:751
 trace_lock_acquire include/trace/events/lock.h:24 [inline]
 lock_acquire+0x5f/0x360 kernel/locking/lockdep.c:5831
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162
 debug_object_activate+0xbb/0x420 lib/debugobjects.c:818
 debug_hrtimer_activate kernel/time/hrtimer.c:438 [inline]
 debug_activate kernel/time/hrtimer.c:477 [inline]
 enqueue_hrtimer+0x30/0x3a0 kernel/time/hrtimer.c:1081
 __run_hrtimer kernel/time/hrtimer.c:1794 [inline]
 __hrtimer_run_queues+0x656/0xc60 kernel/time/hrtimer.c:1841
 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline]
 __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1058
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1052
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xa8/0x110 kernel/locking/spinlock.c:194
Code: 74 05 e8 2b b2 45 f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> d3 3a 0e f6 65 8b 05 dc e8 3f 07 85 c0 74 40 48 c7 04 24 0e 36
RSP: 0018:ffffc90003097b60 EFLAGS: 00000206
RAX: adf8eefa1f7f8700 RBX: 0000000000000a06 RCX: adf8eefa1f7f8700
RDX: 0000000000000007 RSI: ffffffff8dba1162 RDI: 0000000000000001
RBP: ffffc90003097bf0 R08: ffffffff8fc36c77 R09: 1ffffffff1f86d8e
R10: dffffc0000000000 R11: fffffbfff1f86d8f R12: dffffc0000000000
R13: ffff8880b8627ac0 R14: ffff8880b8627ac0 R15: 1ffff92000612f6c
 clock_was_set+0x63b/0x7c0 kernel/time/hrtimer.c:965
 do_settimeofday64+0x41d/0x630 kernel/time/timekeeping.c:1460
 __do_sys_clock_settime kernel/time/posix-timers.c:1131 [inline]
 __se_sys_clock_settime kernel/time/posix-timers.c:1115 [inline]
 __x64_sys_clock_settime+0x22c/0x280 kernel/time/posix-timers.c:1115
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f32cb18eec9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f32cc063038 EFLAGS: 00000246 ORIG_RAX: 00000000000000e3
RAX: ffffffffffffffda RBX: 00007f32cb3e6180 RCX: 00007f32cb18eec9
RDX: 0000000000000000 RSI: 0000200000000240 RDI: 0000000000000000
RBP: 00007f32cb211f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f32cb3e6218 R14: 00007f32cb3e6180 R15: 00007fffbdab7458
 </TASK>
task:syz.1.4174      state:R  running task     stack:21192 pid:18517 tgid:18510 ppid:5881   task_flags:0x400140 flags:0x00080001
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7256
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:211
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:deref_stack_reg+0x1a7/0x230 arch/x86/kernel/unwind_orc.c:406
Code: 46 49 8d 40 08 48 39 d8 0f 97 c1 4c 39 f0 0f 96 c0 20 c8 3c 01 75 30 4c 89 c7 49 89 f7 e8 11 08 00 00 49 89 c6 48 8b 5c 24 18 <48> 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 03 a2 b1 00
RSP: 0018:ffffc9000472da20 EFLAGS: 00000202
RAX: ffffc9000472f8b0 RBX: ffffc9000472db88 RCX: 0000000000000001
RDX: ffffc9000472db88 RSI: dffffc0000000000 RDI: ffffc9000472f7b0
RBP: 1ffff920008e5b69 R08: ffffc9000472f7b0 R09: 0000000000000000
R10: ffffc9000472db98 R11: fffff520008e5b75 R12: 1ffff920008e5b6a
R13: 1ffff920008e5b6b R14: ffffc9000472f8b0 R15: dffffc0000000000
 unwind_next_frame+0x17c4/0x2390 arch/x86/kernel/unwind_orc.c:-1
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:56 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
 poison_kmalloc_redzone mm/kasan/common.c:400 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:417
 kasan_kmalloc include/linux/kasan.h:262 [inline]
 __kmalloc_cache_noprof+0x3d5/0x6f0 mm/slub.c:5724
 kmalloc_noprof include/linux/slab.h:957 [inline]
 kzalloc_noprof include/linux/slab.h:1094 [inline]
 ref_tracker_alloc+0x133/0x460 lib/ref_tracker.c:271
 __netdev_tracker_alloc include/linux/netdevice.h:4390 [inline]
 netdev_tracker_alloc include/linux/netdevice.h:4402 [inline]
 netdev_get_by_index+0x79/0xb0 net/core/dev.c:1008
 fib6_nh_init+0x1cd/0x2020 net/ipv6/route.c:3590
 ip6_route_info_create_nh+0x16a/0xab0 net/ipv6/route.c:3890
 addrconf_f6i_alloc+0x203/0x450 net/ipv6/route.c:4682
 ipv6_add_addr+0x56e/0x1090 net/ipv6/addrconf.c:1126
 add_addr+0x8b/0x2d0 net/ipv6/addrconf.c:3201
 add_v4_addrs+0x70c/0xbd0 net/ipv6/addrconf.c:3263
 addrconf_gre_config net/ipv6/addrconf.c:3545 [inline]
 addrconf_init_auto_addrs+0x6da/0xa30 net/ipv6/addrconf.c:3559
 addrconf_notify+0xacc/0x1010 net/ipv6/addrconf.c:3740
 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85
 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline]
 call_netdevice_notifiers net/core/dev.c:2281 [inline]
 __dev_notify_flags+0x18d/0x2e0 net/core/dev.c:-1
 rtnl_configure_link net/core/rtnetlink.c:3599 [inline]
 rtnl_newlink_create+0x61c/0xb00 net/core/rtnetlink.c:3843
 __rtnl_newlink net/core/rtnetlink.c:3950 [inline]
 rtnl_newlink+0x16e4/0x1c80 net/core/rtnetlink.c:4065
 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6954
 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:729
 ____sys_sendmsg+0x505/0x830 net/socket.c:2617
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2671
 __sys_sendmsg net/socket.c:2703 [inline]
 __do_sys_sendmsg net/socket.c:2708 [inline]
 __se_sys_sendmsg net/socket.c:2706 [inline]
 __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2706
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7efe05f8eec9
RSP: 002b:00007efe06d65038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007efe061e5fa0 RCX: 00007efe05f8eec9
RDX: 0000000000000000 RSI: 0000200000000100 RDI: 0000000000000004
RBP: 00007efe06011f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007efe061e6038 R14: 00007efe061e5fa0 R15: 00007fff368a7268
 </TASK>
rcu: rcu_preempt kthread starved for 6325 jiffies! g88137 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:26464 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7026
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 33 71 28 00 f3 0f 1e fa fb f4 <e9> c8 e6 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8e007d80 EFLAGS: 000002c6
RAX: c48495e83244d300 RBX: ffffffff81971c07 RCX: c48495e83244d300
RDX: 0000000000000001 RSI: ffffffff8dba1162 RDI: ffffffff8c03da60
RBP: ffffffff8e007ea8 R08: ffff8880b8632fdb R09: 1ffff110170c65fb
R10: dffffc0000000000 R11: ffffed10170c65fc R12: ffffffff8fc36c70
R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1c12a40
FS:  0000000000000000(0000) GS:ffff8881259fc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbfcaf8dd30 CR3: 000000007548e000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
 default_idle+0x13/0x20 arch/x86/kernel/process.c:767
 default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:190 [inline]
 do_idle+0x1e7/0x510 kernel/sched/idle.c:330
 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
 rest_init+0x2de/0x300 init/main.c:757
 start_kernel+0x3ae/0x410 init/main.c:1111
 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
 common_startup_64+0x13e/0x147
 </TASK>