rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (3 ticks this GP) idle=9a6c/1/0x4000000000000000 softirq=87207/87207 fqs=2 rcu: (detected by 0, t=10502 jiffies, g=130581, q=155 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 16116 Comm: syz-executor.4 Not tainted 6.9.0-syzkaller-09699-geb6a9339efeb #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 RIP: 0010:lockdep_recursion_finish kernel/locking/lockdep.c:467 [inline] RIP: 0010:lock_acquire kernel/locking/lockdep.c:5756 [inline] RIP: 0010:lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 Code: 00 00 4c 89 f7 6a 00 41 0f 94 c1 48 89 c5 6a 00 45 0f b6 c9 ff b4 24 00 01 00 00 41 57 8b 4c 24 2c 8b 74 24 28 e8 ef ae ff ff <48> c7 c7 60 ae 2c 8b 48 83 c4 28 e8 5f 0b 7b 09 b8 ff ff ff ff 65 RSP: 0018:ffffc90000a18bd8 EFLAGS: 00000086 RAX: 0000000000000001 RBX: 1ffff92000143182 RCX: 000000001e271038 RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffffffff9425f6e0 RBP: 0000000000000000 R08: 0000000000000000 R09: fffffbfff284be50 R10: ffffffff9425f287 R11: 0000000000000003 R12: 0000000000000001 R13: 0000000000000001 R14: ffffffff8e652ea0 R15: 0000000000000000 FS: 00007f324beb96c0(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2be30000 CR3: 000000004b510000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: debug_objects_fill_pool lib/debugobjects.c:614 [inline] debug_object_activate+0x14c/0x540 lib/debugobjects.c:704 debug_hrtimer_activate kernel/time/hrtimer.c:423 [inline] debug_activate kernel/time/hrtimer.c:478 [inline] enqueue_hrtimer+0x25/0x3c0 kernel/time/hrtimer.c:1085 __run_hrtimer kernel/time/hrtimer.c:1704 [inline] __hrtimer_run_queues+0xaac/0xcc0 kernel/time/hrtimer.c:1751 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1813 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline] __sysvec_apic_timer_interrupt+0x10f/0x450 arch/x86/kernel/apic/apic.c:1049 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194 Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 d6 51 81 f6 48 89 df e8 be ce 81 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 e5 0e 73 f6 65 8b 05 56 5b 19 75 85 c0 74 16 5b RSP: 0018:ffffc9000329f0c8 EFLAGS: 00000246 RAX: 0000000000000002 RBX: ffff88805ad602e8 RCX: 1ffffffff2863e46 RDX: 0000000000000000 RSI: ffffffff8b2cab60 RDI: ffffffff8b8fcac0 RBP: 0000000000000246 R08: 0000000000000001 R09: fffffbfff284be8d R10: ffffffff9425f46f R11: 0000000000000004 R12: 17d14a98e50de0f6 R13: 0000000000000246 R14: ffff88805ad600f0 R15: 0000000000000002 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] taprio_change+0x28c4/0x3960 net/sched/sch_taprio.c:1971 taprio_init+0x6b1/0x940 net/sched/sch_taprio.c:2112 qdisc_create+0x4f3/0x1100 net/sched/sch_api.c:1355 tc_modify_qdisc+0x4d8/0x1c40 net/sched/sch_api.c:1777 rtnetlink_rcv_msg+0x3c7/0xe60 net/core/rtnetlink.c:6595 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2564 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0x542/0x820 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0xab5/0xc90 net/socket.c:2585 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2639 __sys_sendmsg+0x117/0x1f0 net/socket.c:2668 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f324b07cee9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f324beb90c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f324b1abf80 RCX: 00007f324b07cee9 RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 000000000000000d RBP: 00007f324b0c949e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f324b1abf80 R15: 00007ffe2d31c3e8 rcu: rcu_preempt kthread starved for 10494 jiffies! g130581 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:28552 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6837 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2000 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2202 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 5309 Comm: kworker/u8:16 Not tainted 6.9.0-syzkaller-09699-geb6a9339efeb #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline] RIP: 0010:smp_call_function_many_cond+0x4e7/0x1420 kernel/smp.c:855 Code: 0c 00 85 ed 74 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 f4 4c 89 f5 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 7b 39 0c 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 f7 0c 00 00 8b 43 08 31 RSP: 0018:ffffc90004407908 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b9344980 RCX: ffffffff8181af2b RDX: ffff8880220e9e00 RSI: ffffffff8181af05 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000006 R12: ffffed1017268931 R13: 0000000000000001 R14: ffff8880b9344988 R15: ffff8880b923fdc0 FS: 0000000000000000(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000000d97a000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1023 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2069 [inline] text_poke_bp_batch+0x22b/0x760 arch/x86/kernel/alternative.c:2279 text_poke_flush arch/x86/kernel/alternative.c:2470 [inline] text_poke_flush arch/x86/kernel/alternative.c:2467 [inline] text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2477 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x1d7/0x400 kernel/jump_label.c:882 static_key_enable_cpuslocked+0x1b7/0x270 kernel/jump_label.c:205 static_key_enable+0x1a/0x20 kernel/jump_label.c:218 toggle_allocation_gate mm/kfence/core.c:826 [inline] toggle_allocation_gate+0xf8/0x250 mm/kfence/core.c:818 process_one_work+0x9fb/0x1b60 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3393 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244