rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 GPs behind) idle=406c/1/0x4000000000000000 softirq=65493/65495 fqs=1
rcu: (detected by 0, t=10506 jiffies, g=50601, q=669 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 14780 Comm: syz.4.3839 Not tainted 6.15.0-rc4-syzkaller-00147-gebd297a2affa #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
RIP: 0010:mark_lock+0x6/0x610 kernel/locking/lockdep.c:4715
Code: 80 e2 2b 8e e8 db b8 6a 03 e9 4a fd ff ff 66 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 48 89 e5 41 57 <41> 56 41 55 41 54 53 48 83 e4 f0 48 83 ec 70 65 48 8b 05 5b fb 0b
RSP: 0018:ffffc90000a08cd0 EFLAGS: 00000002
RAX: 000000000000000c RBX: ffff88805b588b68 RCX: 0000000000000000
RDX: 0000000000000008 RSI: ffff88805b588b68 RDI: ffff88805b588000
RBP: ffffc90000a08cd8 R08: 0000000000080000 R09: 0000000000000001
R10: 0000000000000000 R11: ffff8880b8527858 R12: 0000000000000002
R13: 0000000000000003 R14: ffff88805b588000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888124ae2000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2ef1cff8 CR3: 000000000e180000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
mark_usage kernel/locking/lockdep.c:4675 [inline]
__lock_acquire+0x499/0x1ba0 kernel/locking/lockdep.c:5189
lock_acquire kernel/locking/lockdep.c:5866 [inline]
lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5823
__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:1765 [inline]
__hrtimer_run_queues+0x2bc/0xad0 kernel/time/hrtimer.c:1825
hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
__sysvec_apic_timer_interrupt+0x108/0x3f0 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:get_current arch/x86/include/asm/current.h:25 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:216
Code: e9 2d b8 5a 00 be 03 00 00 00 5b e9 72 7f 15 03 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 34 24 <65> 48 8b 15 18 ad e8 11 65 8b 05 29 ad e8 11 a9 00 01 ff 00 74 1d
RSP: 0018:ffffc90003adf7e0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff820af94b
RDX: ffff88805b588000 RSI: ffffffff820af952 RDI: 0000000000000004
RBP: 00000000000001fd R08: 0000000000000004 R09: 00000000000001fd
R10: 00000000000000c5 R11: 0000000000000000 R12: 0000000000000001
R13: 00000000000000c5 R14: ffff88804fbf9000 R15: 00000000000000c4
__tlb_remove_folio_pages_size.constprop.0+0x162/0x560 mm/mmu_gather.c:202
zap_present_folio_ptes mm/memory.c:1530 [inline]
zap_present_ptes mm/memory.c:1586 [inline]
do_zap_pte_range mm/memory.c:1687 [inline]
zap_pte_range mm/memory.c:1731 [inline]
zap_pmd_range mm/memory.c:1823 [inline]
zap_pud_range mm/memory.c:1852 [inline]
zap_p4d_range mm/memory.c:1873 [inline]
unmap_page_range+0x156e/0x4390 mm/memory.c:1894
unmap_single_vma+0x194/0x2a0 mm/memory.c:1940
unmap_vmas+0x22c/0x490 mm/memory.c:1984
exit_mmap+0x1b9/0xb90 mm/mmap.c:1284
__mmput+0x12a/0x410 kernel/fork.c:1379
mmput+0x62/0x70 kernel/fork.c:1401
exit_mm kernel/exit.c:589 [inline]
do_exit+0x9d1/0x2c30 kernel/exit.c:940
do_group_exit+0xd3/0x2a0 kernel/exit.c:1102
__do_sys_exit_group kernel/exit.c:1113 [inline]
__se_sys_exit_group kernel/exit.c:1111 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1111
x64_sys_call+0x1530/0x1730 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1879f8e969
Code: Unable to access opcode bytes at 0x7f1879f8e93f.
RSP: 002b:00007ffcb5a18ad8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1879f8e969
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffcb5a18b3c R08: 00000005b5a18bcf R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000333
R13: 00000000000927c0 R14: 00000000000445ef R15: 00007ffcb5a18b90
rcu: rcu_preempt kthread starved for 10500 jiffies! g50601 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:27192 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x116f/0x5de0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6860
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2046
rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2248
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 13274 Comm: kworker/u8:31 Not tainted 6.15.0-rc4-syzkaller-00147-gebd297a2affa #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0x4a5/0x1290 kernel/smp.c:885
Code: 89 ee e8 be 12 0c 00 85 ed 74 48 48 8b 44 24 20 49 89 c4 83 e0 07 49 c1 ec 03 48 89 c5 4d 01 f4 83 c5 03 e8 5d 17 0c 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 de 0b 00 00 8b 43 08 31
RSP: 0000:ffffc9000bac7938 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b853f740 RCX: ffffffff81af1bb9
RDX: ffff88807faca440 RSI: ffffffff81af1b93 RDI: 0000000000000005
RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffed10170a7ee9
R13: 0000000000000001 R14: dffffc0000000000 R15: ffff8880b843b040
FS: 0000000000000000(0000) GS:ffff8881249e2000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2b22a3 CR3: 000000000e180000 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:2455 [inline]
text_poke_bp_batch+0x220/0x760 arch/x86/kernel/alternative.c:2665
text_poke_flush arch/x86/kernel/alternative.c:2856 [inline]
text_poke_flush arch/x86/kernel/alternative.c:2853 [inline]
text_poke_finish+0x30/0x40 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:850 [inline]
toggle_allocation_gate+0xfa/0x280 mm/kfence/core.c:842
process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245