rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P1163/2:b..l P38/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=7849, q=1094 ncpus=2)
task:khugepaged state:R running task stack:29264 pid:38 tgid:38 ppid:2 task_flags:0x200040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_notrace+0x62/0xe0 kernel/sched/core.c:7140
preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
rcu_is_watching+0x8e/0xc0 kernel/rcu/tree.c:752
trace_lock_acquire include/trace/events/lock.h:24 [inline]
lock_acquire+0x2cd/0x330 kernel/locking/lockdep.c:5831
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
start_flush_work kernel/workqueue.c:4183 [inline]
__flush_work+0x10c/0xcc0 kernel/workqueue.c:4241
__lru_add_drain_all+0x50f/0x6f0 mm/swap.c:885
khugepaged_do_scan mm/khugepaged.c:2557 [inline]
khugepaged+0x11e/0x1690 mm/khugepaged.c:2626
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
task:kworker/u8:8 state:R running task stack:25320 pid:1163 tgid:1163 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:unwind_next_frame+0x16a5/0x20b0 arch/x86/kernel/unwind_orc.c:680
Code: 4e 05 00 00 49 8b 45 10 48 39 dd 0f 87 e4 f7 ff ff 48 39 d8 0f 86 db f7 ff ff 48 8d 53 08 48 39 d5 0f 92 c1 48 39 d0 0f 93 c0 <84> c1 0f 84 c3 f7 ff ff 48 39 5c 24 10 0f 82 b8 f7 ff ff 48 b8 00
RSP: 0000:ffffc900045ff230 EFLAGS: 00000206
RAX: ffffc90004600001 RBX: ffffc900045ffea8 RCX: ffffc90004600001
RDX: ffffc900045ffeb0 RSI: ffffc900045ffe78 RDI: ffffc900045ff2b0
RBP: ffffc900045f8000 R08: 0000000000000001 R09: 00000000f2b35ee1
R10: 0000000000000002 R11: 00000000000086e8 R12: ffffc900045ff2f0
R13: ffffc900045ff2a0 R14: ffffc900045ffea8 R15: ffffc900045ff2d4
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x33/0x60 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
kmalloc_noprof include/linux/slab.h:957 [inline]
kzalloc_noprof include/linux/slab.h:1094 [inline]
ref_tracker_alloc+0x18e/0x5b0 lib/ref_tracker.c:271
__netdev_tracker_alloc include/linux/netdevice.h:4400 [inline]
netdev_hold include/linux/netdevice.h:4429 [inline]
dst_init+0xda/0x580 net/core/dst.c:52
dst_alloc+0xbb/0x1a0 net/core/dst.c:93
ip6_dst_alloc net/ipv6/route.c:342 [inline]
icmp6_dst_alloc+0x79/0x4f0 net/ipv6/route.c:3333
ndisc_send_skb+0x13ed/0x1f50 net/ipv6/ndisc.c:491
ndisc_send_rs+0x129/0x670 net/ipv6/ndisc.c:722
addrconf_dad_completed+0x49d/0x10d0 net/ipv6/addrconf.c:4360
addrconf_dad_work+0x855/0x14f0 net/ipv6/addrconf.c:4268
process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
process_scheduled_works kernel/workqueue.c:3340 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: rcu_preempt kthread starved for 10563 jiffies! g7849 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:28440 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
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 10/25/2025
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: 96 5f 02 c3 cc cc cc cc 0f 1f 00 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 13 19 12 00 fb f4 cc 35 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffffff8e007df8 EFLAGS: 000002c6
RAX: 000000000011e8c7 RBX: 0000000000000000 RCX: ffffffff8b7846d9
RDX: 0000000000000000 RSI: ffffffff8dace97a RDI: ffffffff8bf2b400
RBP: fffffbfff1c12f68 R08: 0000000000000001 R09: ffffed101708673d
R10: ffff8880b84339eb R11: ffffffff8e098670 R12: 0000000000000000
R13: ffffffff8e097b40 R14: ffffffff9088b8d0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881248f5000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055fa0b0f6000 CR3: 0000000075cd5000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x38d/0x510 kernel/sched/idle.c:332
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430
rest_init+0x16b/0x2b0 init/main.c:757
start_kernel+0x3ef/0x4d0 init/main.c:1206
x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x148