rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=088c/1/0x4000000000000000 softirq=45842/45843 fqs=1 rcu: (detected by 1, t=10502 jiffies, g=73289, q=110 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 11865 Comm: syz-executor.3 Not tainted 6.4.0-next-20230628-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023 RIP: 0010:__rcu_read_lock+0xf/0xf0 kernel/rcu/tree_plugin.h:401 Code: 00 e9 4d ff ff ff e8 00 22 6a 00 e9 66 ff ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 48 b8 00 00 00 00 00 fc ff df 55 <53> 65 48 8b 1c 25 c0 b9 03 00 48 8d bb 3c 04 00 00 48 89 fa 48 c1 RSP: 0018:ffffc90000007d80 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffff888047426340 RCX: 0000000000000000 RDX: 1ffff11008e84c6c RSI: 0000000000000004 RDI: ffff888047426360 RBP: 176cd0d5087f0000 R08: 0000000000000000 R09: ffffed1008e84c5d R10: ffff8880474262eb R11: 0000000000000001 R12: ffff888047bd68c0 R13: 0000000000000000 R14: ffff888047bd7110 R15: ffff888047bd6800 FS: 00007f5ae7665700(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff9b3b85998 CR3: 000000003f63d000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_lock include/linux/rcupdate.h:746 [inline] advance_sched+0x6bf/0xd20 net/sched/sch_taprio.c:996 __run_hrtimer kernel/time/hrtimer.c:1688 [inline] __hrtimer_run_queues+0x604/0xc00 kernel/time/hrtimer.c:1752 hrtimer_interrupt+0x320/0x7b0 kernel/time/hrtimer.c:1814 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1098 [inline] __sysvec_apic_timer_interrupt+0x14a/0x430 arch/x86/kernel/apic/apic.c:1115 sysvec_apic_timer_interrupt+0x92/0xc0 arch/x86/kernel/apic/apic.c:1109 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x3c/0x70 kernel/locking/spinlock.c:194 Code: 74 24 10 e8 36 21 42 f7 48 89 ef e8 0e 91 42 f7 81 e3 00 02 00 00 75 25 9c 58 f6 c4 02 75 2d 48 85 db 74 01 fb bf 01 00 00 00 3f 4c 34 f7 65 8b 05 30 68 df 75 85 c0 74 0a 5b 5d c3 e8 3c 5f RSP: 0018:ffffc900216bfa98 EFLAGS: 00000206 RAX: 0000000000000002 RBX: 0000000000000200 RCX: 1ffffffff230cf16 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001 RBP: ffff8880b982b880 R08: 0000000000000001 R09: fffffbfff230cdd0 R10: 0000000000000001 R11: 0000000000000001 R12: fe232ac934f1f3b0 R13: 0000000000000000 R14: 0000011934f1f3b0 R15: dffffc0000000000 clock_was_set+0x61a/0x830 kernel/time/hrtimer.c:972 timekeeping_inject_offset+0x4b4/0x620 kernel/time/timekeeping.c:1395 do_adjtimex+0x333/0xa40 kernel/time/timekeeping.c:2444 do_clock_adjtime kernel/time/posix-timers.c:1159 [inline] __do_sys_clock_adjtime+0x163/0x270 kernel/time/posix-timers.c:1171 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f5ae688c389 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f5ae7665168 EFLAGS: 00000246 ORIG_RAX: 0000000000000131 RAX: ffffffffffffffda RBX: 00007f5ae69ac050 RCX: 00007f5ae688c389 RDX: 0000000000000000 RSI: 0000000020000040 RDI: 0000000000000000 RBP: 00007f5ae68d7493 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffdf50f1e6f R14: 00007f5ae7665300 R15: 0000000000022000 rcu: rcu_preempt kthread starved for 10495 jiffies! g73289 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:28264 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0xc9a/0x5880 kernel/sched/core.c:6710 schedule+0xde/0x1a0 kernel/sched/core.c:6786 schedule_timeout+0x14e/0x2b0 kernel/time/timer.c:2167 rcu_gp_fqs_loop+0x190/0x910 kernel/rcu/tree.c:1609 rcu_gp_kthread+0x23a/0x360 kernel/rcu/tree.c:1808 kthread+0x344/0x440 kernel/kthread.c:389 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 PID: 6681 Comm: kworker/u4:1 Not tainted 6.4.0-next-20230628-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:300 [inline] RIP: 0010:smp_call_function_many_cond+0x694/0x1720 kernel/smp.c:844 Code: 89 ee e8 5f 4f 0b 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 1e 53 0b 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 d1 0d 00 00 8b 43 08 31 RSP: 0018:ffffc9000aee7948 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b9845020 RCX: 0000000000000000 RDX: ffff888027680000 RSI: ffffffff8179b842 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: ffffed1017308a05 R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2ce25000 CR3: 000000000c775000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x5a/0xa0 kernel/smp.c:1012 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1938 [inline] text_poke_bp_batch+0x24f/0x780 arch/x86/kernel/alternative.c:2148 text_poke_flush arch/x86/kernel/alternative.c:2339 [inline] text_poke_flush arch/x86/kernel/alternative.c:2336 [inline] text_poke_finish+0x1a/0x30 arch/x86/kernel/alternative.c:2346 arch_jump_label_transform_apply+0x17/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x32f/0x410 kernel/jump_label.c:829 static_key_enable_cpuslocked+0x1b5/0x270 kernel/jump_label.c:205 static_key_enable+0x1a/0x20 kernel/jump_label.c:218 toggle_allocation_gate mm/kfence/core.c:831 [inline] toggle_allocation_gate+0xf8/0x230 mm/kfence/core.c:823 process_one_work+0xa34/0x16f0 kernel/workqueue.c:2597 worker_thread+0x67d/0x10c0 kernel/workqueue.c:2748 kthread+0x344/0x440 kernel/kthread.c:389 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308