rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=0c5/1/0x4000000000000000 softirq=29843/29847 fqs=0 (detected by 0, t=10505 jiffies, g=39685, q=246) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 10090 Comm: syz-executor.4 Not tainted 5.15.153-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 RIP: 0010:rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:331 [inline] RIP: 0010:rcu_is_watching+0x36/0xa0 kernel/rcu/tree.c:1123 Code: e8 3f 19 b1 08 89 c3 83 f8 08 73 72 49 bf 00 00 00 00 00 fc ff df 4c 8d 34 dd f0 07 35 8c 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 <74> 08 4c 89 f7 e8 f0 04 5f 00 48 c7 c3 c8 b2 03 00 49 03 1e 48 89 RSP: 0018:ffffc90000dd0ac0 EFLAGS: 00000046 RAX: 1ffffffff186a0ff RBX: 0000000000000001 RCX: ffffffff8162b218 RDX: 0000000000000000 RSI: ffffffff8ad88fa0 RDI: ffffffff8ad88f60 RBP: ffffc90000dd0c10 R08: dffffc0000000000 R09: fffffbfff1bc72a6 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920001ba168 R13: ffffffff840c2724 R14: ffffffff8c3507f8 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2c723000 CR3: 0000000064f0e000 CR4: 00000000003526e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: trace_lock_release include/trace/events/lock.h:58 [inline] lock_release+0xb9/0x9a0 kernel/locking/lockdep.c:5634 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:158 [inline] _raw_spin_unlock_irqrestore+0x75/0x130 kernel/locking/spinlock.c:194 debug_object_activate+0x2f4/0x4e0 lib/debugobjects.c:711 debug_hrtimer_activate kernel/time/hrtimer.c:420 [inline] debug_activate kernel/time/hrtimer.c:475 [inline] enqueue_hrtimer+0x30/0x390 kernel/time/hrtimer.c:1084 __run_hrtimer kernel/time/hrtimer.c:1703 [inline] __hrtimer_run_queues+0x6b6/0xcf0 kernel/time/hrtimer.c:1750 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline] __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:check_kcov_mode kernel/kcov.c:174 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x32/0x60 kernel/kcov.c:197 Code: 04 36 82 7e 65 8b 15 05 36 82 7e f7 c2 00 01 ff 00 74 11 f7 c2 00 01 00 00 74 35 83 b9 34 16 00 00 00 74 2c 8b 91 10 16 00 00 <83> fa 02 75 21 48 8b 91 18 16 00 00 48 8b 32 48 8d 7e 01 8b 89 14 RSP: 0018:ffffc90003277d78 EFLAGS: 00000246 RAX: ffffffff814ccc71 RBX: ffffc90003270000 RCX: ffff888055578000 RDX: 0000000000000000 RSI: 0000000043736564 RDI: ffffc90003270878 RBP: ffffc90003277ec0 R08: ffffffff8155ba91 R09: ffffed10043ff42a R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000 R13: 1ffff1100aaaf0ab R14: ffff888016cda700 R15: 0000000000000878 stack_not_used include/linux/sched/task_stack.h:105 [inline] check_stack_usage kernel/exit.c:757 [inline] do_exit+0x1a01/0x2480 kernel/exit.c:915 do_group_exit+0x144/0x310 kernel/exit.c:994 __do_sys_exit_group kernel/exit.c:1005 [inline] __se_sys_exit_group kernel/exit.c:1003 [inline] __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1003 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f3de8538de9 Code: Unable to access opcode bytes at RIP 0x7f3de8538dbf. RSP: 002b:00007ffcf5dfea58 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 000000000000001e RCX: 00007f3de8538de9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000001 R08: 00000000000000e5 R09: 0000000000000000 R10: 0000001b2fa20000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000001 rcu: rcu_preempt kthread starved for 10505 jiffies! g39685 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:27000 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376 schedule+0x11b/0x1f0 kernel/sched/core.c:6459 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1884 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145 kthread+0x3f6/0x4f0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 0 CPU: 0 PID: 10091 Comm: syz-executor.4 Not tainted 5.15.153-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline] rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline] rcu_pending kernel/rcu/tree.c:3932 [inline] rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619 update_process_times+0x196/0x200 kernel/time/timer.c:1788 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1686 [inline] __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1750 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline] __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline] RIP: 0010:smp_call_function_many_cond+0xa93/0xd90 kernel/smp.c:969 Code: 04 03 84 c0 0f 85 84 00 00 00 45 8b 7d 00 44 89 fe 83 e6 01 31 ff e8 1c cf 0b 00 41 83 e7 01 75 07 e8 b1 cb 0b 00 eb 41 f3 90 <48> b8 00 00 00 00 00 fc ff df 0f b6 04 03 84 c0 75 11 41 f7 45 00 RSP: 0018:ffffc90002dd74a0 EFLAGS: 00000293 RAX: ffffffff81746e24 RBX: 1ffff110173680b1 RCX: ffff888014dc3b80 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90002dd75e0 R08: ffffffff81746df4 R09: ffffed1017347673 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000001 R13: ffff8880b9b40588 R14: ffff8880b9a3b380 R15: 0000000000000001 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1135 __flush_tlb_multi arch/x86/include/asm/paravirt.h:87 [inline] flush_tlb_multi arch/x86/mm/tlb.c:900 [inline] flush_tlb_mm_range+0x2a5/0x4a0 arch/x86/mm/tlb.c:986 tlb_flush arch/x86/include/asm/tlb.h:23 [inline] tlb_flush_mmu_tlbonly+0x1ab/0x410 include/asm-generic/tlb.h:430 tlb_flush_mmu mm/mmu_gather.c:246 [inline] tlb_finish_mmu+0xd2/0x320 mm/mmu_gather.c:338 exit_mmap+0x3cd/0x670 mm/mmap.c:3188 __mmput+0x112/0x3b0 kernel/fork.c:1126 exit_mm+0x688/0x7f0 kernel/exit.c:548 do_exit+0x626/0x2480 kernel/exit.c:859 do_group_exit+0x144/0x310 kernel/exit.c:994 get_signal+0xc66/0x14e0 kernel/signal.c:2889 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:172 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:208 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x5d/0x250 kernel/entry/common.c:301 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f3de8538de9 Code: Unable to access opcode bytes at RIP 0x7f3de8538dbf. RSP: 002b:00007f3de6ab9178 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000001 RBX: 00007f3de8666f88 RCX: 00007f3de8538de9 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f3de8666f8c RBP: 00007f3de8666f80 R08: 0000000000000010 R09: 00007f3de6ab96c0 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3de8666f8c R13: 000000000000000b R14: 00007ffcf5dfe680 R15: 00007ffcf5dfe768