rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=637c/1/0x4000000000000000 softirq=5601/5602 fqs=0 (detected by 1, t=10502 jiffies, g=5409, q=134 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 3270 Comm: kworker/0:3 Not tainted 6.0.0-rc7-syzkaller-00345-gf76349cf4145 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 Workqueue: events_freezable_power_ sync_hw_clock RIP: 0010:div64_u64 include/linux/math64.h:69 [inline] RIP: 0010:taprio_set_budget net/sched/sch_taprio.c:556 [inline] RIP: 0010:advance_sched+0x3ce/0x9a0 net/sched/sch_taprio.c:762 Code: 38 d0 7c 08 84 d2 0f 85 5d 05 00 00 41 8b 44 24 2c 4d 8d 74 24 20 31 d2 be 04 00 00 00 4c 89 f7 48 69 c0 e8 03 00 00 48 f7 f5 <48> 89 c5 e8 8a 52 3a fa 4c 89 f2 48 b8 00 00 00 00 00 fc ff df 48 RSP: 0018:ffffc90000007dd0 EFLAGS: 00000006 RAX: 0000000140000002 RBX: ffff88807db11340 RCX: ffff8880277508ac RDX: 00000000000000c8 RSI: 0000000000000004 RDI: ffff8880277508a0 RBP: 0000000000000190 R08: 0000000000000000 R09: ffff88807db112e7 R10: ffffed100fb6225c R11: 0000000000000000 R12: ffff888027750880 R13: 17e7bcfbafcf79f7 R14: ffff8880277508a0 R15: 17e7bcfbafcf79f7 FS: 0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fdd2ba73dff CR3: 00000000176fc000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x5fa/0xe40 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1112 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:lock_acquire+0x1ef/0x570 kernel/locking/lockdep.c:5634 Code: d0 a3 7e 83 f8 01 0f 85 e8 02 00 00 9c 58 f6 c4 02 0f 85 fb 02 00 00 48 83 7c 24 08 00 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24 RSP: 0018:ffffc900032b7c28 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff92000656f87 RCX: 0000000000000001 RDX: 1ffff1100f73a186 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000001 R08: 0000000000000001 R09: ffffffff8f799fdf R10: fffffbfff1ef33fb R11: 1ffffffff1ffa93b R12: 0000000000000000 R13: 0000000000000000 R14: ffff888011876138 R15: 0000000000000000 process_one_work+0x8db/0x1610 kernel/workqueue.c:2264 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 rcu: rcu_preempt kthread starved for 10502 jiffies! g5409 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:28112 pid: 16 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5182 [inline] __schedule+0xadf/0x52b0 kernel/sched/core.c:6494 schedule+0xda/0x1b0 kernel/sched/core.c:6570 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1935 rcu_gp_fqs_loop+0x190/0x910 kernel/rcu/tree.c:1657 rcu_gp_kthread+0x236/0x360 kernel/rcu/tree.c:1854 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 1 CPU: 1 PID: 8 Comm: kworker/u4:0 Not tainted 6.0.0-rc7-syzkaller-00345-gf76349cf4145 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 Workqueue: events_unbound toggle_allocation_gate Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x46/0x14f lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x206/0x250 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline] rcu_check_gp_kthread_starvation.cold+0x1fb/0x200 kernel/rcu/tree_stall.h:514 print_other_cpu_stall kernel/rcu/tree_stall.h:619 [inline] check_cpu_stall kernel/rcu/tree_stall.h:762 [inline] rcu_pending kernel/rcu/tree.c:3660 [inline] rcu_sched_clock_irq+0x2404/0x2530 kernel/rcu/tree.c:2342 update_process_times+0x11a/0x1a0 kernel/time/timer.c:1839 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:243 tick_sched_timer+0xee/0x120 kernel/time/tick-sched.c:1480 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x1c0/0xe40 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1112 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:csd_lock_wait kernel/smp.c:414 [inline] RIP: 0010:smp_call_function_many_cond+0x5c3/0x1430 kernel/smp.c:988 Code: 89 ee e8 c0 b1 0a 00 85 ed 74 48 48 8b 44 24 08 49 89 c4 83 e0 07 49 c1 ec 03 48 89 c5 4d 01 f4 83 c5 03 e8 df b4 0a 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 b5 0b 00 00 8b 43 08 31 RSP: 0018:ffffc900002ef948 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b9a44fc0 RCX: 0000000000000000 RDX: ffff8880121d0200 RSI: ffffffff81708341 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffed10173489f9 R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000001 on_each_cpu_cond_mask+0x56/0xa0 kernel/smp.c:1154 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1302 [inline] text_poke_bp_batch+0x3f6/0x6c0 arch/x86/kernel/alternative.c:1543 text_poke_flush arch/x86/kernel/alternative.c:1660 [inline] text_poke_flush arch/x86/kernel/alternative.c:1657 [inline] text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1667 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146 jump_label_update+0x32f/0x410 kernel/jump_label.c:801 static_key_disable_cpuslocked+0x152/0x1b0 kernel/jump_label.c:207 static_key_disable+0x16/0x20 kernel/jump_label.c:215 toggle_allocation_gate mm/kfence/core.c:825 [inline] toggle_allocation_gate+0x183/0x390 mm/kfence/core.c:803 process_one_work+0x991/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306