rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=5f5c/1/0x4000000000000000 softirq=99594/99595 fqs=2
rcu: (detected by 1, t=10502 jiffies, g=84545, q=497 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 17916 Comm: syz.3.3058 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:lock_acquire kernel/locking/lockdep.c:5868 [inline]
RIP: 0010:lock_acquire+0x157/0x350 kernel/locking/lockdep.c:5825
Code: 00 00 9c 8f 04 24 fa 48 c7 c7 76 f8 90 8d e8 80 7e b4 09 45 89 e0 89 e9 44 89 ea 65 ff 05 09 8d e2 11 48 81 24 24 00 02 00 00 <44> 89 f6 48 89 df 6a 00 6a 00 6a 00 ff b4 24 88 00 00 00 41 0f 94
RSP: 0018:ffffc90000007d18 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffffff8e1c4120 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffffff8d90f876 RDI: ffffffff8bd010c0
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000
R10: ffff8880283ea2eb R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888124e85000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b307f4ff8 CR3: 000000000df82000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 000000000000000e DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
advance_sched+0x699/0xc80 net/sched/sch_taprio.c:990
__run_hrtimer kernel/time/hrtimer.c:1777 [inline]
__hrtimer_run_queues+0x202/0xad0 kernel/time/hrtimer.c:1841
hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1903
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline]
__sysvec_apic_timer_interrupt+0x108/0x3f0 arch/x86/kernel/apic/apic.c:1058
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1052
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5872
Code: 4c e2 11 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 d2 d0 c7 0e 0f 82 74 02 00 00 8b 35 2a 01 c8 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 29 4c e2 11 0f 85 c7 02 00 00 48 83 c4
RSP: 0018:ffffc9000430f158 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e1c4120 RCX: 00000000ef9d33e4
RDX: 0000000000000000 RSI: ffffffff8d7fb115 RDI: ffffffff8bd010c0
RBP: 0000000000000002 R08: 0ac0d5affe09d4ff R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
__update_page_owner_free_handle.constprop.0+0x4d/0x4a0 mm/page_owner.c:271
__reset_page_owner+0x93/0x1a0 mm/page_owner.c:309
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1394 [inline]
free_unref_folios+0xa31/0x1610 mm/page_alloc.c:2963
folios_put_refs+0x4be/0x750 mm/swap.c:1002
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x58f/0x1150 mm/shmem.c:1120
shmem_truncate_range mm/shmem.c:1232 [inline]
shmem_evict_inode+0x3a1/0xbe0 mm/shmem.c:1360
evict+0x3e3/0x920 fs/inode.c:810
iput_final fs/inode.c:1914 [inline]
iput.part.0+0x6a9/0xb00 fs/inode.c:1966
iput+0x35/0x40 fs/inode.c:1929
dentry_unlink_inode+0x29c/0x480 fs/dcache.c:466
__dentry_kill+0x1d0/0x600 fs/dcache.c:669
dput.part.0+0x4b1/0x9b0 fs/dcache.c:911
dput+0x1f/0x30 fs/dcache.c:901
__fput+0x51c/0xb70 fs/file_table.c:476
task_work_run+0x150/0x240 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x86f/0x2bf0 kernel/exit.c:966
do_group_exit+0xd3/0x2a0 kernel/exit.c:1107
get_signal+0x2671/0x26d0 kernel/signal.c:3034
arch_do_signal_or_restart+0x8f/0x7c0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x85/0x130 kernel/entry/common.c:40
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x419/0x4e0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f81c838eec9
Code: Unable to access opcode bytes at 0x7f81c838ee9f.
RSP: 002b:00007f81c91400e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f81c85e6368 RCX: 00007f81c838eec9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f81c85e6368
RBP: 00007f81c85e6360 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f81c85e63f8 R14: 00007ffd89039030 R15: 00007ffd89039118
rcu: rcu_preempt kthread starved for 10498 jiffies! g84545 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:27904 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7026
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+0x3c2/0x780 kernel/kthread.c:463
ret_from_fork+0x56a/0x730 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 6795 Comm: kworker/u8:14 Not tainted syzkaller #0 PREEMPT(full)
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:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xe07/0x1600 kernel/smp.c:877
Code: 10 49 89 d5 48 89 d5 48 89 54 24 18 49 c1 ed 03 83 e5 07 4d 01 e5 83 c5 03 e8 b5 0b 0c 00 f3 90 41 0f b6 45 00 40 38 c5 7c 08 <84> c0 0f 85 e0 05 00 00 8b 43 08 31 ff 83 e0 01 41 89 c6 89 c6 e8
RSP: 0018:ffffc9001d29f888 EFLAGS: 00000206
RAX: 0000000000000000 RBX: ffff8880b8642800 RCX: ffffffff81af2a21
RDX: ffff88802bf2c900 RSI: ffffffff81af29fb RDI: 0000000000000005
RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: dffffc0000000000
R13: ffffed10170c8501 R14: 0000000000000001 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888124f85000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff911310300 CR3: 000000000df82000 CR4: 00000000003526f0
Call Trace:
on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1043
on_each_cpu include/linux/smp.h:71 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2653 [inline]
smp_text_poke_batch_finish+0x27b/0xdb0 arch/x86/kernel/alternative.c:2863
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
jump_label_update+0x376/0x550 kernel/jump_label.c:919
static_key_enable_cpuslocked+0x1b7/0x270 kernel/jump_label.c:210
static_key_enable+0x1a/0x20 kernel/jump_label.c:223
toggle_allocation_gate mm/kfence/core.c:852 [inline]
toggle_allocation_gate+0xfa/0x280 mm/kfence/core.c:844
process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3263
process_scheduled_works kernel/workqueue.c:3346 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427
kthread+0x3c2/0x780 kernel/kthread.c:463
ret_from_fork+0x56a/0x730 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245