rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (2 ticks this GP) idle=abac/1/0x4000000000000000 softirq=16913/16927 fqs=1 rcu: (detected by 0, t=10506 jiffies, g=17793, q=328 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 7459 Comm: syz-executor.1 Not tainted 6.9.0-syzkaller-08544-g4b377b4868ef #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:19 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:67 [inline] RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:103 [inline] RIP: 0010:lock_acquire+0x15d/0x550 kernel/locking/lockdep.c:5750 Code: c3 dc 0a 00 00 48 89 d8 48 c1 e8 03 42 0f b6 04 28 84 c0 0f 85 e5 02 00 00 83 3b 00 0f 85 62 01 00 00 4c 8d bc 24 80 00 00 00 <4c> 89 fb 48 c1 eb 03 42 80 3c 2b 00 74 08 4c 89 ff e8 3d f9 88 00 RSP: 0018:ffffc90000a18a40 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff88802738e4dc RCX: ffffffff81727814 RDX: 0000000000000000 RSI: ffffffff8c1fae00 RDI: ffffffff8c1fadc0 RBP: ffffc90000a18b88 R08: ffffffff8facbbef R09: 1ffffffff1f5977d R10: dffffc0000000000 R11: fffffbfff1f5977e R12: 1ffff92000143150 R13: dffffc0000000000 R14: 0000000000000000 R15: ffffc90000a18ac0 FS: 00007f9b82a6b6c0(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000206ce030 CR3: 000000001ea68000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 debug_object_deactivate+0x158/0x390 lib/debugobjects.c:763 debug_hrtimer_deactivate kernel/time/hrtimer.c:428 [inline] debug_deactivate+0x1b/0x220 kernel/time/hrtimer.c:484 __run_hrtimer kernel/time/hrtimer.c:1655 [inline] __hrtimer_run_queues+0x30f/0xd50 kernel/time/hrtimer.c:1751 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1813 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline] __sysvec_apic_timer_interrupt+0x110/0x3f0 arch/x86/kernel/apic/apic.c:1049 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 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+0xd8/0x140 kernel/locking/spinlock.c:194 Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 8e 97 68 f6 f6 44 24 21 02 75 52 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 83 cc d2 f5 65 8b 05 f4 f9 70 74 85 c0 74 43 48 c7 04 24 0e 36 RSP: 0018:ffffc90003026b40 EFLAGS: 00000206 RAX: 0606fbafa0503c00 RBX: 1ffff92000604d6c RCX: ffffffff8172ea4a RDX: dffffc0000000000 RSI: ffffffff8bcab5c0 RDI: 0000000000000001 RBP: ffffc90003026bd0 R08: ffffffff92f9c6e7 R09: 1ffffffff25f38dc R10: dffffc0000000000 R11: fffffbfff25f38dd R12: dffffc0000000000 R13: 1ffff92000604d68 R14: ffffc90003026b60 R15: 0000000000000246 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] taprio_change+0x339b/0x42d0 net/sched/sch_taprio.c:1971 taprio_init+0x9da/0xc80 net/sched/sch_taprio.c:2112 qdisc_create+0x9d4/0x11a0 net/sched/sch_api.c:1355 tc_modify_qdisc+0xa26/0x1e40 net/sched/sch_api.c:1777 rtnetlink_rcv_msg+0x89b/0x10d0 net/core/rtnetlink.c:6595 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x8e1/0xcb0 net/netlink/af_netlink.c:1905 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_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9b81c7cee9 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:00007f9b82a6b0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f9b81dabf80 RCX: 00007f9b81c7cee9 RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000008 RBP: 00007f9b81cc949e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f9b81dabf80 R15: 00007fff2e794328 rcu: rcu_preempt kthread starved for 10500 jiffies! g17793 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:24880 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0x17e8/0x4a50 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6837 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x2df/0x1370 kernel/rcu/tree.c:2000 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2202 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/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: 7184 Comm: kworker/u8:17 Not tainted 6.9.0-syzkaller-08544-g4b377b4868ef #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+0x1894/0x2a00 kernel/smp.c:855 Code: 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 a5 0c 0c 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 50 08 0c 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 34 08 RSP: 0018:ffffc900141476e0 EFLAGS: 00000293 RAX: ffffffff818a299c RBX: 1ffff110172a8879 RCX: ffff88807c6d5a00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900141478e0 R08: ffffffff818a296b R09: 1ffffffff25f38b0 R10: dffffc0000000000 R11: fffffbfff25f38b1 R12: dffffc0000000000 R13: ffff8880b95443c8 R14: ffff8880b943f780 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000206da030 CR3: 000000000e132000 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:2069 [inline] text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2279 text_poke_flush arch/x86/kernel/alternative.c:2470 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2477 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:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd70 kernel/workqueue.c:3393 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244