rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (2 GPs behind) idle=3f4c/1/0x4000000000000000 softirq=15315/15316 fqs=1 rcu: (detected by 1, t=10502 jiffies, g=10377, q=289 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 36 Comm: kworker/u8:2 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Workqueue: ipv6_addrconf addrconf_dad_work RIP: 0010:_static_cpu_has arch/x86/include/asm/cpufeature.h:101 [inline] RIP: 0010:addr_has_metadata mm/kasan/kasan.h:334 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:188 [inline] RIP: 0010:kasan_check_range+0x30/0x2c0 mm/kasan/generic.c:200 Code: 57 41 56 41 55 41 54 53 b0 01 48 85 f6 0f 84 ba 01 00 00 4c 8d 04 37 49 39 f8 0f 82 82 02 00 00 49 b9 00 00 00 00 00 80 ff ff 11 cc cc cc f3 0f 1e fa 49 b9 00 00 00 00 00 00 00 ff f3 0f 1e RSP: 0018:ffffc90000007b48 EFLAGS: 00000012 RAX: ffffffff89259b01 RBX: ffff88807b00a000 RCX: ffffffff89259b90 RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88807b00a158 RBP: ffffc90000007c60 R08: ffff88807b00a160 R09: ffff800000000000 R10: dffffc0000000000 R11: ffffed100f60145e R12: ffff88807b00a360 R13: 1ffff92000000f74 R14: 186ba97d216015be R15: ffff888056accc00 FS: 0000000000000000(0000) GS:ffff888126378000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000000600 CR3: 000000001d6e8000 CR4: 00000000003526f0 Call Trace: instrument_atomic_read_write include/linux/instrumented.h:96 [inline] test_and_set_bit include/asm-generic/bitops/instrumented-atomic.h:71 [inline] __netif_schedule+0x90/0x2c0 net/core/dev.c:3376 advance_sched+0xa9a/0xc90 net/sched/sch_taprio.c:991 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x52c/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+0x108/0x410 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 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:deref_stack_reg arch/x86/kernel/unwind_orc.c:406 [inline] RIP: 0010:unwind_next_frame+0xc52/0x2390 arch/x86/kernel/unwind_orc.c:585 Code: 96 c0 20 c8 3c 01 0f 85 df 0c 00 00 48 89 df e8 84 23 00 00 48 89 c3 48 bd 00 00 00 00 00 fc ff df 48 8b 44 24 30 80 3c 28 00 <4c> 8b 7c 24 18 74 08 4c 89 ff e8 1f bb b1 00 49 89 1f 48 8b 44 24 RSP: 0018:ffffc90000ac6f18 EFLAGS: 00000246 RAX: 1ffff92000158e06 RBX: ffffffff8189e7ee RCX: 1ffff92000158d01 RDX: ffffffff90798622 RSI: 0000000000000002 RDI: ffffc90000ac7a78 RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffffff81723db5 R10: ffffc90000ac7038 R11: ffffffff81aad930 R12: ffffc90000ac8000 R13: 1ffff92000158dff R14: ffffc90000ac6fe8 R15: ffffc90000ac0000 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 __kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:587 kasan_save_free_info mm/kasan/kasan.h:406 [inline] poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2514 [inline] slab_free mm/slub.c:6566 [inline] kmem_cache_free+0x19b/0x690 mm/slub.c:6676 skb_release_data+0x62d/0x7c0 net/core/skbuff.c:1087 skb_release_all net/core/skbuff.c:1152 [inline] __kfree_skb net/core/skbuff.c:1166 [inline] consume_skb+0x9e/0xf0 net/core/skbuff.c:1398 netlink_broadcast_filtered+0xec7/0x1000 net/netlink/af_netlink.c:1537 nlmsg_multicast_filtered include/net/netlink.h:1165 [inline] nlmsg_multicast include/net/netlink.h:1184 [inline] nlmsg_notify+0xf0/0x1a0 net/netlink/af_netlink.c:2595 inet6_ifa_notify net/ipv6/addrconf.c:5621 [inline] __ipv6_ifa_notify+0x236/0xac0 net/ipv6/addrconf.c:6270 ipv6_ifa_notify net/ipv6/addrconf.c:6322 [inline] addrconf_dad_completed+0x180/0xd60 net/ipv6/addrconf.c:4320 addrconf_dad_work+0xc36/0x14b0 net/ipv6/addrconf.c:-1 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x436/0x7d0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: rcu_preempt kthread timer wakeup didn't happen for 10499 jiffies! g10377 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=3826 rcu: rcu_preempt kthread starved for 10500 jiffies! g10377 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:27944 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: 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+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x436/0x7d0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245