rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=474c/1/0x4000000000000000 softirq=6005/6007 fqs=0 rcu: (detected by 0, t=10506 jiffies, g=6717, q=76 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 5091 Comm: syz-executor353 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 RIP: 0010:hlock_class kernel/locking/lockdep.c:228 [inline] RIP: 0010:mark_lock+0xa2/0x350 kernel/locking/lockdep.c:4656 Code: 00 8b 1b 81 e3 ff 1f 00 00 48 89 d8 48 c1 e8 06 48 8d 3c c5 00 55 ce 92 be 08 00 00 00 e8 b6 3a 86 00 48 0f a3 1d ce 48 5c 11 <73> 10 48 69 c3 c8 00 00 00 48 8d 98 00 b4 9c 92 eb 68 48 c7 c0 60 RSP: 0018:ffffc90000a089e8 EFLAGS: 00000057 RAX: 0000000000000001 RBX: 00000000000006f9 RCX: ffffffff81720c2a RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff92ce55d8 RBP: 0000000000000008 R08: ffffffff92ce55df R09: 1ffffffff259cabb R10: dffffc0000000000 R11: fffffbfff259cabc R12: 0000000000000001 R13: dffffc0000000000 R14: 0000000000000100 R15: ffff888021d1e578 FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f98fff062d0 CR3: 00000000112da000 CR4: 0000000000350ef0 Call Trace: mark_usage kernel/locking/lockdep.c:4599 [inline] __lock_acquire+0xc0a/0x1fd0 kernel/locking/lockdep.c:5091 lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] advance_sched+0xab/0xca0 net/sched/sch_taprio.c:924 __run_hrtimer kernel/time/hrtimer.c:1692 [inline] __hrtimer_run_queues+0x597/0xd00 kernel/time/hrtimer.c:1756 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1818 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline] __sysvec_apic_timer_interrupt+0x109/0x3a0 arch/x86/kernel/apic/apic.c:1049 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:rcu_lock_release include/linux/rcupdate.h:308 [inline] RIP: 0010:rcu_read_unlock_sched include/linux/rcupdate.h:863 [inline] RIP: 0010:pfn_valid+0x3d8/0x440 include/linux/mmzone.h:2026 Code: 0e e0 90 ff c6 05 94 9e 6d 0d 01 48 c7 c7 c0 d2 b7 8b be 5e 03 00 00 48 c7 c2 60 d3 b7 8b e8 1f e5 6d ff 48 c7 c7 a0 1f 13 8e <4c> 89 f6 e8 60 aa 6d ff bf 01 00 00 00 e8 b6 d6 60 ff 65 8b 1d 07 RSP: 0018:ffffc9000441f5c0 EFLAGS: 00000293 RAX: ffffffff8204145a RBX: 0000000000000001 RCX: ffff888021d1da00 RDX: 0000000000000000 RSI: ffffffff8bfed2e0 RDI: ffffffff8e131fa0 RBP: 0000000000000001 R08: ffffffff82041448 R09: 1ffffffff259caa0 R10: dffffc0000000000 R11: fffffbfff259caa1 R12: dffffc0000000000 R13: 0000000000076b80 R14: ffffffff82041286 R15: ffff88813fff91c0 page_table_check_clear+0x21/0x730 mm/page_table_check.c:68 zap_pte_range mm/memory.c:1452 [inline] zap_pmd_range mm/memory.c:1597 [inline] zap_pud_range mm/memory.c:1626 [inline] zap_p4d_range mm/memory.c:1647 [inline] unmap_page_range+0x1f7a/0x3610 mm/memory.c:1668 unmap_vmas+0x3cc/0x5f0 mm/memory.c:1758 exit_mmap+0x2c6/0xd40 mm/mmap.c:3287 __mmput+0x115/0x3c0 kernel/fork.c:1345 exit_mm+0x220/0x310 kernel/exit.c:569 do_exit+0x99e/0x27e0 kernel/exit.c:865 do_group_exit+0x207/0x2c0 kernel/exit.c:1027 __do_sys_exit_group kernel/exit.c:1038 [inline] __se_sys_exit_group kernel/exit.c:1036 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1036 do_syscall_64+0xfd/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 RIP: 0033:0x7f98ffe82c69 Code: Unable to access opcode bytes at 0x7f98ffe82c3f. RSP: 002b:00007ffd0e42d378 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f98ffe82c69 RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000 RBP: 00007f98fff03390 R08: ffffffffffffffb8 R09: 0000000100000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f98fff03390 R13: 0000000000000000 R14: 00007f98fff05ec0 R15: 00007f98ffe53130 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.837 msecs rcu: rcu_preempt kthread starved for 10506 jiffies! g6717 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:24176 pid:16 tgid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5409 [inline] __schedule+0x17d3/0x4a20 kernel/sched/core.c:6736 __schedule_loop kernel/sched/core.c:6813 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6828 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2572 rcu_gp_fqs_loop+0x2df/0x1370 kernel/rcu/tree.c:1663 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:1862 kthread+0x2f2/0x390 kernel/kthread.c:388 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 2413 Comm: kworker/u8:7 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline] RIP: 0010:smp_call_function_many_cond+0x1855/0x2960 kernel/smp.c:855 Code: 89 e6 83 e6 01 31 ff e8 d9 d5 0b 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 84 d1 0b 00 eb 38 f3 90 42 0f b6 04 23 <84> c0 75 11 41 f7 45 00 01 00 00 00 74 1e e8 68 d1 0b 00 eb e4 44 RSP: 0018:ffffc9000938f6e0 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 1ffff110172a8809 RCX: ffff8880297ebc00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000938f8e0 R08: ffffffff818923b7 R09: 1ffffffff259caa0 R10: dffffc0000000000 R11: fffffbfff259caa1 R12: dffffc0000000000 R13: ffff8880b9544048 R14: ffff8880b943f480 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055eda496f000 CR3: 000000000df32000 CR4: 0000000000350ef0 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1023 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2086 [inline] text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2296 text_poke_flush arch/x86/kernel/alternative.c:2487 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2494 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x136/0x260 kernel/jump_label.c:205 static_key_enable+0x1a/0x20 kernel/jump_label.c:218 toggle_allocation_gate+0xb5/0x250 mm/kfence/core.c:826 process_one_work kernel/workqueue.c:3254 [inline] process_scheduled_works+0xa02/0x1770 kernel/workqueue.c:3335 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416 kthread+0x2f2/0x390 kernel/kthread.c:388 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243