rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 GPs behind) idle=8574/1/0x4000000000000000 softirq=28089/28098 fqs=0
rcu: (detected by 0, t=10505 jiffies, g=25305, q=179 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 9913 Comm: syz.1.1806 Not tainted 6.14.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:separate_irq_context kernel/locking/lockdep.c:4701 [inline]
RIP: 0010:__lock_acquire+0xb18/0x3c40 kernel/locking/lockdep.c:5212
Code: 00 00 00 00 00 fc ff df 48 8d 7d 21 48 89 fa 48 c1 ea 03 0f b6 04 02 48 89 fa 83 e2 07 38 d0 7f 09 84 c0 74 05 e8 d8 87 86 00 <49> 8d 7f 21 0f b6 6d 21 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48
RSP: 0018:ffffc90000a28be8 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 852e1a6758f7af37 RCX: ffffffff81968092
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88802641d409
RBP: ffff88802641d3e8 R08: 0000000000000000 R09: fffffbfff2dd8d99
R10: ffffffff96ec6ccf R11: 0000000000000004 R12: ffff88802641d409
R13: ffff88802641c880 R14: 0000000000000002 R15: ffff88802641d410
FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000006c3d0000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5851
__raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
_raw_spin_lock_irq+0x36/0x50 kernel/locking/spinlock.c:170
__run_hrtimer kernel/time/hrtimer.c:1805 [inline]
__hrtimer_run_queues+0x2be/0xae0 kernel/time/hrtimer.c:1865
hrtimer_interrupt+0x392/0x8e0 kernel/time/hrtimer.c:1927
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
__sysvec_apic_timer_interrupt+0x10f/0x400 arch/x86/kernel/apic/apic.c:1055
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire.part.0+0x155/0x380 kernel/locking/lockdep.c:5816
Code: b8 ff ff ff ff 65 0f c1 05 90 c8 6b 7e 83 f8 01 0f 85 d0 01 00 00 9c 58 f6 c4 02 0f 85 e5 01 00 00 48 85 ed 0f 85 b6 01 00 00 <48> b8 00 00 00 00 00 fc ff df 48 01 c3 48 c7 03 00 00 00 00 48 c7
RSP: 0018:ffffc900046a74b0 EFLAGS: 00000206
RAX: 0000000000000046 RBX: 1ffff920008d4e97 RCX: 0000000057475fcc
RDX: 0000000000000001 RSI: ffffffff8b6cfee0 RDI: ffffffff8bd36aa0
RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff2dd8d98
R10: ffffffff96ec6cc7 R11: 0000000000000003 R12: 0000000000000000
R13: ffffffff8e1bd080 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
rcu_read_lock_sched include/linux/rcupdate.h:941 [inline]
pfn_valid include/linux/mmzone.h:2067 [inline]
page_table_check_clear mm/page_table_check.c:70 [inline]
__page_table_check_pte_clear+0x1c0/0x580 mm/page_table_check.c:169
page_table_check_pte_clear include/linux/page_table_check.h:49 [inline]
ptep_get_and_clear_full arch/x86/include/asm/pgtable.h:1337 [inline]
get_and_clear_full_ptes include/linux/pgtable.h:712 [inline]
zap_present_folio_ptes mm/memory.c:1510 [inline]
zap_present_ptes mm/memory.c:1595 [inline]
do_zap_pte_range mm/memory.c:1697 [inline]
zap_pte_range mm/memory.c:1741 [inline]
zap_pmd_range mm/memory.c:1833 [inline]
zap_pud_range mm/memory.c:1862 [inline]
zap_p4d_range mm/memory.c:1883 [inline]
unmap_page_range+0x2393/0x4390 mm/memory.c:1904
unmap_single_vma+0x194/0x2b0 mm/memory.c:1950
unmap_vmas+0x22f/0x490 mm/memory.c:1994
exit_mmap+0x1c1/0xba0 mm/mmap.c:1284
__mmput+0x12a/0x410 kernel/fork.c:1356
mmput+0x62/0x70 kernel/fork.c:1378
exit_mm kernel/exit.c:570 [inline]
do_exit+0x9ba/0x2d70 kernel/exit.c:925
do_group_exit+0xd3/0x2a0 kernel/exit.c:1087
get_signal+0x24ed/0x26c0 kernel/signal.c:3036
arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb40c98d169
Code: Unable to access opcode bytes at 0x7fb40c98d13f.
RSP: 002b:00007fb40d8040e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007fb40cba5fa8 RCX: 00007fb40c98d169
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fb40cba5fa8
RBP: 00007fb40cba5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb40cba5fac
R13: 0000000000000000 R14: 00007ffdf1d5ce30 R15: 00007ffdf1d5cf18
rcu: rcu_preempt kthread starved for 10505 jiffies! g25305 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:27552 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5378 [inline]
__schedule+0xf43/0x5890 kernel/sched/core.c:6765
__schedule_loop kernel/sched/core.c:6842 [inline]
schedule+0xe7/0x350 kernel/sched/core.c:6857
schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2024
rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2226
kthread+0x3af/0x750 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 3012 Comm: kworker/u8:6 Not tainted 6.14.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0x4c6/0x12c0 kernel/smp.c:885
Code: 0c 00 85 ed 74 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 fc 4c 89 fd 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 ac 0e 0c 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 e8 0b 00 00 8b 43 08 31
RSP: 0018:ffffc9000bcaf928 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b8744a80 RCX: ffffffff81ade3da
RDX: ffff888031068000 RSI: ffffffff81ade3b4 RDI: 0000000000000005
RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000006 R12: ffffed10170e8951
R13: 0000000000000001 R14: ffff8880b863fe80 R15: ffff8880b8744a88
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c37f277 CR3: 000000000df80000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1052
on_each_cpu include/linux/smp.h:71 [inline]
text_poke_sync arch/x86/kernel/alternative.c:2118 [inline]
text_poke_bp_batch+0x22b/0x760 arch/x86/kernel/alternative.c:2328
text_poke_flush arch/x86/kernel/alternative.c:2519 [inline]
text_poke_flush arch/x86/kernel/alternative.c:2516 [inline]
text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2526
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
jump_label_update+0x1d7/0x400 kernel/jump_label.c:920
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:850 [inline]
toggle_allocation_gate+0xfc/0x260 mm/kfence/core.c:842
process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3238
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3400
kthread+0x3af/0x750 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244