rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=e5bc/1/0x4000000000000000 softirq=7080/7081 fqs=1 rcu: (detected by 0, t=10503 jiffies, g=8445, q=74 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 5082 Comm: syz-executor145 Not tainted 6.8.0-rc4-syzkaller-00034-g8d3dea210042 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 RIP: 0010:rcu_is_watching+0x0/0xb0 kernel/rcu/tree.c:696 Code: 4c 89 f6 e8 b2 b3 5e 03 e9 2b ff ff ff e8 48 bb eb 09 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 41 57 41 56 53 65 ff 05 38 ed 88 7e e8 6b d9 eb 09 89 RSP: 0018:ffffc900001f0c88 EFLAGS: 00000002 RAX: 0000000080010202 RBX: ffffffff8975cbb2 RCX: ffff88801bb45940 RDX: ffff88801bb45940 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000001 R08: ffffffff8975cc69 R09: 1ffff110054f0e2b R10: dffffc0000000000 R11: ffffed10054f0e2c R12: dffffc0000000000 R13: ffff88802c079008 R14: ffff88802c079000 R15: ffff88802a787360 FS: 0000555557410380(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fac1179f0f0 CR3: 000000001ed92000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_unlock include/linux/rcupdate.h:779 [inline] advance_sched+0xac2/0xca0 net/sched/sch_taprio.c:998 __run_hrtimer kernel/time/hrtimer.c:1689 [inline] __hrtimer_run_queues+0x594/0xd00 kernel/time/hrtimer.c:1753 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1815 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1065 [inline] __sysvec_apic_timer_interrupt+0x107/0x3a0 arch/x86/kernel/apic/apic.c:1082 sysvec_apic_timer_interrupt+0x92/0xb0 arch/x86/kernel/apic/apic.c:1076 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xd8/0x140 kernel/locking/spinlock.c:194 Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 4e 3a 84 f6 f6 44 24 21 02 75 52 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 33 fd f2 f5 65 8b 05 84 6f 92 74 85 c0 74 43 48 c7 04 24 0e 36 RSP: 0018:ffffc90003a7ea60 EFLAGS: 00000206 RAX: 20ed11c59fcf6a00 RBX: 1ffff9200074fd50 RCX: ffffffff8171882a RDX: dffffc0000000000 RSI: ffffffff8baab5e0 RDI: 0000000000000001 RBP: ffffc90003a7eaf0 R08: ffffffff92c8a4e7 R09: 1ffffffff259149c R10: dffffc0000000000 R11: fffffbfff259149d R12: dffffc0000000000 R13: 1ffff9200074fd4c R14: ffffc90003a7ea80 R15: 0000000000000246 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] taprio_change+0x4912/0x57d0 net/sched/sch_taprio.c:1993 taprio_init+0x9da/0xc80 net/sched/sch_taprio.c:2134 qdisc_create+0x9d4/0x1190 net/sched/sch_api.c:1355 tc_modify_qdisc+0xa26/0x1e40 net/sched/sch_api.c:1776 rtnetlink_rcv_msg+0x885/0x1040 net/core/rtnetlink.c:6615 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2543 netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline] netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1367 netlink_sendmsg+0xa3b/0xd70 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2584 ___sys_sendmsg net/socket.c:2638 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2667 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x7fac11722ba9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 d1 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:00007ffd265a0898 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fac11722ba9 RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000004 RBP: 0000000000000000 R08: 0000000100000000 R09: 0000000100000000 R10: 0000000100000000 R11: 0000000000000246 R12: 00007ffd265a08f0 R13: 0000000000000001 R14: 00007ffd265a08f0 R15: 0000000000000003 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.808 msecs rcu: rcu_preempt kthread starved for 10498 jiffies! g8445 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:25072 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5400 [inline] __schedule+0x17d1/0x49f0 kernel/sched/core.c:6727 __schedule_loop kernel/sched/core.c:6802 [inline] schedule+0x149/0x260 kernel/sched/core.c:6817 schedule_timeout+0x1bd/0x310 kernel/time/timer.c:2183 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:1663 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:1862 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 11 Comm: kworker/u4:0 Not tainted 6.8.0-rc4-syzkaller-00034-g8d3dea210042 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline] RIP: 0010:smp_call_function_many_cond+0x1850/0x2960 kernel/smp.c:855 Code: 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 99 d4 0b 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 44 d0 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 28 d0 RSP: 0018:ffffc90000107720 EFLAGS: 00000293 RAX: ffffffff81879c18 RBX: 1ffff110172a8395 RCX: ffff8880172b3b80 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90000107920 R08: ffffffff81879be7 R09: 1ffffffff2591484 R10: dffffc0000000000 R11: fffffbfff2591485 R12: dffffc0000000000 R13: ffff8880b9541ca8 R14: ffff8880b943da80 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fac117703b0 CR3: 000000000df32000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 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:2087 [inline] text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2297 text_poke_flush arch/x86/kernel/alternative.c:2488 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2495 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:2633 [inline] process_scheduled_works+0x913/0x1420 kernel/workqueue.c:2706 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2787 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242