rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 0, t=10502 jiffies, g=7957, q=25 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294955514-4294945012), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10502 jiffies! g7957 f0x2 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:24656 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: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 5080 Comm: syz-executor182 Not tainted 6.8.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:32 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:67 [inline] RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:127 [inline] RIP: 0010:lock_acquire+0x22d/0x530 kernel/locking/lockdep.c:5757 Code: 0f 85 ac 01 00 00 49 89 de 48 c1 eb 03 42 80 3c 2b 00 74 08 4c 89 f7 e8 11 73 84 00 48 c7 44 24 60 00 00 00 00 9c 8f 44 24 60 <42> 80 3c 2b 00 74 08 4c 89 f7 e8 04 72 84 00 f6 44 24 61 02 0f 85 RSP: 0018:ffffc900001f0b60 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 1ffff9200003e178 RCX: 0000000000000001 RDX: dffffc0000000000 RSI: ffffffff8baac740 RDI: ffffffff8bfe6c60 RBP: ffffc900001f0ca8 R08: ffffffff92c8c42f R09: 1ffffffff2591885 R10: dffffc0000000000 R11: fffffbfff2591886 R12: 1ffff9200003e174 R13: dffffc0000000000 R14: ffffc900001f0bc0 R15: 0000000000000046 FS: 00005555558a4380(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000600 CR3: 0000000028e3c000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0xd3/0x120 kernel/locking/spinlock.c:170 __run_hrtimer kernel/time/hrtimer.c:1693 [inline] __hrtimer_run_queues+0x659/0xd00 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 fe 19 84 f6 f6 44 24 21 02 75 52 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 f3 dc f2 f5 65 8b 05 94 4e 92 74 85 c0 74 43 48 c7 04 24 0e 36 RSP: 0018:ffffc9000395eca0 EFLAGS: 00000206 RAX: bb49747661e62a00 RBX: 1ffff9200072bd98 RCX: ffffffff817188da RDX: dffffc0000000000 RSI: ffffffff8baab5c0 RDI: 0000000000000001 RBP: ffffc9000395ed30 R08: ffffffff92c8c4e7 R09: 1ffffffff259189c R10: dffffc0000000000 R11: fffffbfff259189d R12: dffffc0000000000 R13: 1ffff9200072bd94 R14: ffffc9000395ecc0 R15: 0000000000000246 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] taprio_change+0x4912/0x57d0 net/sched/sch_taprio.c:1993 qdisc_change net/sched/sch_api.c:1416 [inline] tc_modify_qdisc+0x190d/0x1e40 net/sched/sch_api.c:1746 rtnetlink_rcv_msg+0x885/0x1040 net/core/rtnetlink.c:6618 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: 0033:0x7f537aee8c29 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:00007fff81b8a778 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f537aee8c29 RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000006 RBP: 00000000000f4240 R08: 0000000100000000 R09: 0000000100000000 R10: 0000000100000000 R11: 0000000000000246 R12: 00007fff81b8a7d0 R13: 0000000000000001 R14: 00007fff81b8a7d0 R15: 0000000000000003 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.592 msecs