rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (10500 ticks this GP) idle=d4f/1/0x4000000000000000 softirq=33735/33735 fqs=0 (t=10500 jiffies g=41909 q=197) rcu: rcu_preempt kthread timer wakeup didn't happen for 10499 jiffies! g41909 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=31228 rcu: rcu_preempt kthread starved for 10500 jiffies! g41909 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27064 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 schedule+0x11b/0x1f0 kernel/sched/core.c:6456 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914 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:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 1 CPU: 1 PID: 8169 Comm: syz.4.903 Not tainted 5.15.166-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 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_cpu_stall+0x31b/0x600 kernel/rcu/tree_stall.h:631 check_cpu_stall kernel/rcu/tree_stall.h:727 [inline] rcu_pending kernel/rcu/tree.c:3932 [inline] rcu_sched_clock_irq+0x8d9/0x1150 kernel/rcu/tree.c:2619 update_process_times+0x196/0x200 kernel/time/timer.c:1818 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:1688 [inline] __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1752 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814 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:lock_release+0x62d/0x9a0 kernel/locking/lockdep.c:5647 Code: 3c 3b 00 74 08 4c 89 f7 e8 c0 49 67 00 f6 84 24 91 00 00 00 02 75 6f 41 f7 c5 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 04 27 00 00 00 00 4b c7 44 27 08 00 00 00 00 65 48 8b 04 25 RSP: 0018:ffffc90002dc7dc0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff920005b8fca RCX: ffffc90002dc7e03 RDX: 0000000000000000 RSI: ffffffff8a8b3cc0 RDI: ffffffff8ad90100 RBP: ffffc90002dc7ee8 R08: dffffc0000000000 R09: fffffbfff1bd2b66 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920005b8fc4 R13: 0000000000000246 R14: ffffc90002dc7e50 R15: dffffc0000000000 rcu_read_unlock include/linux/rcupdate.h:772 [inline] __task_pid_nr_ns+0x34c/0x420 kernel/pid.c:501 task_tgid_vnr include/linux/sched.h:1587 [inline] __do_sys_getpid+0x19/0x20 kernel/sys.c:945 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fe069b54ea7 Code: 0b e9 68 fe ff ff 48 83 c4 18 48 8d 3d f2 89 cf 00 5b 5d 41 5c 41 5d 41 5e 41 5f e9 23 f5 fb ff 0f 1f 00 b8 27 00 00 00 0f 05 0f 1f 84 00 00 00 00 00 b8 66 00 00 00 0f 05 c3 0f 1f 84 00 00 RSP: 002b:00007fe067f94b08 EFLAGS: 00000202 ORIG_RAX: 0000000000000027 RAX: ffffffffffffffda RBX: 00007fe067f94c70 RCX: 00007fe069b54ea7 RDX: 00007fe067f94b40 RSI: 00007fe067f94c70 RDI: 0000000000000021 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00007fe069d1713c R13: 0000000000000000 R14: 00007ffc97d57b80 R15: 00007ffc97d57c68 NMI backtrace for cpu 1 CPU: 1 PID: 8169 Comm: syz.4.903 Not tainted 5.15.166-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 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_dump_cpu_stacks+0x223/0x390 kernel/rcu/tree_stall.h:349 print_cpu_stall+0x320/0x600 kernel/rcu/tree_stall.h:633 check_cpu_stall kernel/rcu/tree_stall.h:727 [inline] rcu_pending kernel/rcu/tree.c:3932 [inline] rcu_sched_clock_irq+0x8d9/0x1150 kernel/rcu/tree.c:2619 update_process_times+0x196/0x200 kernel/time/timer.c:1818 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:1688 [inline] __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1752 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814 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:lock_release+0x62d/0x9a0 kernel/locking/lockdep.c:5647 Code: 3c 3b 00 74 08 4c 89 f7 e8 c0 49 67 00 f6 84 24 91 00 00 00 02 75 6f 41 f7 c5 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 04 27 00 00 00 00 4b c7 44 27 08 00 00 00 00 65 48 8b 04 25 RSP: 0018:ffffc90002dc7dc0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff920005b8fca RCX: ffffc90002dc7e03 RDX: 0000000000000000 RSI: ffffffff8a8b3cc0 RDI: ffffffff8ad90100 RBP: ffffc90002dc7ee8 R08: dffffc0000000000 R09: fffffbfff1bd2b66 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920005b8fc4 R13: 0000000000000246 R14: ffffc90002dc7e50 R15: dffffc0000000000 rcu_read_unlock include/linux/rcupdate.h:772 [inline] __task_pid_nr_ns+0x34c/0x420 kernel/pid.c:501 task_tgid_vnr include/linux/sched.h:1587 [inline] __do_sys_getpid+0x19/0x20 kernel/sys.c:945 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fe069b54ea7 Code: 0b e9 68 fe ff ff 48 83 c4 18 48 8d 3d f2 89 cf 00 5b 5d 41 5c 41 5d 41 5e 41 5f e9 23 f5 fb ff 0f 1f 00 b8 27 00 00 00 0f 05 0f 1f 84 00 00 00 00 00 b8 66 00 00 00 0f 05 c3 0f 1f 84 00 00 RSP: 002b:00007fe067f94b08 EFLAGS: 00000202 ORIG_RAX: 0000000000000027 RAX: ffffffffffffffda RBX: 00007fe067f94c70 RCX: 00007fe069b54ea7 RDX: 00007fe067f94b40 RSI: 00007fe067f94c70 RDI: 0000000000000021 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00007fe069d1713c R13: 0000000000000000 R14: 00007ffc97d57b80 R15: 00007ffc97d57c68