rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=2414/1/0x4000000000000000 softirq=28833/28835 fqs=2
(detected by 1, t=10506 jiffies, g=38021, q=179 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 8052 Comm: syz.2.1278 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:85 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x7b/0x290 mm/kasan/generic.c:189
Code: 5c 37 ff 48 c1 eb 03 4e 8d 14 3b 4d 89 d6 4d 29 ce 49 83 fe 10 7f 26 4d 85 f6 0f 84 39 01 00 00 48 f7 d3 4c 01 db 41 80 39 00 <0f> 85 c1 01 00 00 49 ff c1 48 ff c3 75 ee e9 1c 01 00 00 44 89 cb
RSP: 0018:ffffc90000007ba0 EFLAGS: 00000046
RAX: 00000000ffffff01 RBX: ffffffffffffffff RCX: ffffffff816435ee
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffff8880b8e2a580
RBP: ffffc90000007c70 R08: dffffc0000000000 R09: ffffed10171c54b0
R10: ffffed10171c54b1 R11: 1ffff110171c54b0 R12: ffff8880b8e2a590
R13: ffff8880b8e2a588 R14: 0000000000000001 R15: dffffc0000000001
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f822ff8 CR3: 0000000030e91000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
instrument_atomic_read_write include/linux/instrumented.h:102 [inline]
atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:541 [inline]
queued_spin_lock include/asm-generic/qspinlock.h:111 [inline]
do_raw_spin_lock+0x10e/0x280 kernel/locking/spinlock_debug.c:115
__raw_spin_lock_irq include/linux/spinlock_api_smp.h:120 [inline]
_raw_spin_lock_irq+0xab/0xe0 kernel/locking/spinlock.c:170
__run_hrtimer kernel/time/hrtimer.c:1751 [inline]
__hrtimer_run_queues+0x63a/0xd60 kernel/time/hrtimer.c:1811
hrtimer_interrupt+0x3c5/0x9c0 kernel/time/hrtimer.c:1873
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
__sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:folio_inc_refs mm/swap.c:443 [inline]
RIP: 0010:folio_mark_accessed+0x2ff/0x1440 mm/swap.c:470
Code: 4c 89 e7 be 08 00 00 00 e8 ce 9f 22 00 f0 41 80 0c 24 40 e9 1b ff ff ff 49 be 00 00 00 00 80 01 00 00 4c 8b 64 24 40 4d 89 e5 <4d> 21 f5 4c 89 f7 4c 89 ee e8 a3 80 d2 ff 4d 39 f5 75 0a e8 b9 7c
RSP: 0018:ffffc900033473e0 EFLAGS: 00000202
RAX: ffffffff81ae51b1 RBX: 1ffffd400038db71 RCX: ffff888079a23b80
RDX: 0000000000000000 RSI: 0000000000000040 RDI: 0000000000000000
RBP: ffffc90003347490 R08: dffffc0000000000 R09: fffff9400038db71
R10: fffff9400038db71 R11: 1ffffd400038db70 R12: 00fff9800000205e
R13: 00fff9800000205e R14: 0000018000000000 R15: 0000000000000040
zap_pte_range mm/memory.c:1450 [inline]
zap_pmd_range mm/memory.c:1574 [inline]
zap_pud_range mm/memory.c:1603 [inline]
zap_p4d_range mm/memory.c:1624 [inline]
unmap_page_range+0x109a/0x2500 mm/memory.c:1645
unmap_vmas+0x22c/0x330 mm/memory.c:1730
exit_mmap+0x1cc/0x8e0 mm/mmap.c:3250
__mmput+0x118/0x3c0 kernel/fork.c:1200
exit_mm+0x1e6/0x2c0 kernel/exit.c:565
do_exit+0x8c1/0x2400 kernel/exit.c:867
do_group_exit+0x217/0x2d0 kernel/exit.c:1022
get_signal+0x1272/0x1350 kernel/signal.c:2871
arch_do_signal_or_restart+0xb0/0x1230 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fd9b858eec9
Code: Unable to access opcode bytes at 0x7fd9b858ee9f.
RSP: 002b:00007fd9b67f60e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 00007fd9b87e5fa8 RCX: 00007fd9b858eec9
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fd9b87e5fac
RBP: 00007fd9b87e5fa0 R08: 0005ce5c90000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd9b87e6038 R14: 00007ffec6ab15d0 R15: 00007ffec6ab16b8
rcu: rcu_preempt kthread starved for 10495 jiffies! g38021 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:27840 pid:16 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
schedule+0xb9/0x180 kernel/sched/core.c:6637
schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965
rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 PID: 33 Comm: kworker/u4:2 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:424 [inline]
RIP: 0010:smp_call_function_many_cond+0xe7b/0x1270 kernel/smp.c:998
Code: 00 00 00 41 8b 1f 89 de 83 e6 01 31 ff e8 5d d9 0a 00 83 e3 01 48 bb 00 00 00 00 00 fc ff df 75 07 e8 e9 d5 0a 00 eb 37 f3 90 <41> 0f b6 04 1c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 ce d5 0a
RSP: 0018:ffffc90000a9f800 EFLAGS: 00000293
RAX: ffffffff8175f922 RBX: dffffc0000000000 RCX: ffff88801aaa8000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000a9f960 R08: dffffc0000000000 R09: fffffbfff215c449
R10: fffffbfff215c449 R11: 1ffffffff215c448 R12: 1ffff110171c85b5
R13: ffff8880b8f3bb80 R14: 0000000000000000 R15: ffff8880b8e42da8
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f16de7721e0 CR3: 000000000c88e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1166
on_each_cpu include/linux/smp.h:71 [inline]
text_poke_sync arch/x86/kernel/alternative.c:1574 [inline]
text_poke_bp_batch+0x2b0/0x7d0 arch/x86/kernel/alternative.c:1774
text_poke_flush arch/x86/kernel/alternative.c:1965 [inline]
text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1972
arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146
static_key_enable_cpuslocked+0x11f/0x240 kernel/jump_label.c:207
static_key_enable+0x16/0x20 kernel/jump_label.c:220
toggle_allocation_gate+0xb4/0x430 mm/kfence/core.c:805
process_one_work+0x898/0x1160 kernel/workqueue.c:2292
worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295