rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=8974/1/0x4000000000000000 softirq=20988/20989 fqs=1
rcu: 	(detected by 0, t=10502 jiffies, g=16437, q=979 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6445 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
RIP: 0010:lock_acquire+0x67/0x330 kernel/locking/lockdep.c:5833
Code: 00 65 8b 05 ff 8e 77 11 83 f8 08 0f 83 83 01 00 00 89 c0 48 0f a3 05 68 e5 6f 0e 73 0d e8 21 1f 09 00 84 c0 0f 84 ca 01 00 00 <83> 3d a2 17 70 0e 00 0f 84 d3 00 00 00 48 8b b4 24 90 00 00 00 4c
RSP: 0018:ffffc90000a08bc0 EFLAGS: 00000002
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000010002
RDX: 0000000000000000 RSI: ffffffff8c276fe0 RDI: ffffffff8c276fa0
RBP: ffffffff89adcad4 R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff89adca10 R12: 0000000000000000
R13: ffff88804513e2c0 R14: 0000000000000000 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff888125396000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffcbb97a418 CR3: 000000000e54c000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 __raw_spin_lock include/linux/spinlock_api_smp.h:158 [inline]
 _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:341 [inline]
 advance_sched+0xc4/0xc90 net/sched/sch_taprio.c:930
 __run_hrtimer kernel/time/hrtimer.c:1785 [inline]
 __hrtimer_run_queues+0x529/0xc30 kernel/time/hrtimer.c:1849
 hrtimer_interrupt+0x42b/0x1010 kernel/time/hrtimer.c:1911
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
 __sysvec_apic_timer_interrupt+0x102/0x3d0 arch/x86/kernel/apic/apic.c:1062
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:118 [inline]
RIP: 0010:lock_acquire+0x84/0x330 kernel/locking/lockdep.c:5844
Code: e8 21 1f 09 00 84 c0 0f 84 ca 01 00 00 83 3d a2 17 70 0e 00 0f 84 d3 00 00 00 48 8b b4 24 90 00 00 00 4c 89 ef e8 9c 0f 8d 00 <83> 3d 85 17 70 0e 00 0f 84 ce 00 00 00 65 8b 05 28 d4 77 11 85 c0
RSP: 0018:ffffc90003d6f258 EFLAGS: 00000202
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000080000001
RDX: 0000000000000000 RSI: ffffffff817632b2 RDI: 1ffffffff1cec02c
RBP: ffffffff81763295 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc90003d6f418 R11: ffffffff81b02c90 R12: 0000000000000002
R13: ffffffff8e760160 R14: 0000000000000000 R15: 0000000000000000
 rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
 rcu_read_lock include/linux/rcupdate.h:850 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1193 [inline]
 unwind_next_frame+0xc2/0x23c0 arch/x86/kernel/unwind_orc.c:495
 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57
 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556
 __call_rcu_common kernel/rcu/tree.c:3131 [inline]
 call_rcu+0xee/0x890 kernel/rcu/tree.c:3251
 slab_free_hook mm/slub.c:2631 [inline]
 slab_free mm/slub.c:6079 [inline]
 kmem_cache_free+0x447/0x610 mm/slub.c:6205
 anon_vma_free mm/rmap.c:137 [inline]
 __put_anon_vma+0x12b/0x2d0 mm/rmap.c:2892
 put_anon_vma mm/internal.h:215 [inline]
 unlink_anon_vmas+0x58b/0x730 mm/rmap.c:529
 free_pgtables+0x836/0xb70 mm/memory.c:429
 exit_mmap+0x482/0x9c0 mm/mmap.c:1314
 __mmput+0x118/0x430 kernel/fork.c:1174
 exit_mm+0x168/0x220 kernel/exit.c:581
 do_exit+0x62e/0x2310 kernel/exit.c:959
 do_group_exit+0x21b/0x2d0 kernel/exit.c:1112
 __do_sys_exit_group kernel/exit.c:1123 [inline]
 __se_sys_exit_group kernel/exit.c:1121 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1121
 x64_sys_call+0x221a/0x2240 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8a487346c5
Code: Unable to access opcode bytes at 0x7f8a4873469b.
RSP: 002b:00007ffcbb97a328 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007ffcbb97a604 RCX: 00007f8a487346c5
RDX: 00000000000000e7 RSI: ffffffffffffff88 RDI: 0000000000000000
RBP: 0000000000000003 R08: 00007ffcbb97a420 R09: 0000000000000002
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007ffcbb97a660 R14: 00007f8a48944000 R15: 000055ddbbfbad98
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10499 jiffies! g16437 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=7576
rcu: rcu_preempt kthread starved for 10500 jiffies! g16437 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:27624 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5295 [inline]
 __schedule+0x1539/0x5080 kernel/sched/core.c:6907
 __schedule_loop kernel/sched/core.c:6989 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7004
 schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095
 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297
 kthread+0x388/0x470 kernel/kthread.c:467
 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>