rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (2 ticks this GP) idle=2044/1/0x4000000000000000 softirq=15721/15721 fqs=0 rcu: (detected by 1, t=10502 jiffies, g=10517, q=320 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 6080 Comm: syz-executor.0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:__lock_acquire+0xc1/0xd20 kernel/locking/lockdep.c:5138 Code: ff ff 48 8b 3c 24 48 85 c0 0f 84 02 0c 00 00 8b 0d a4 0c dc 17 8b 97 28 0b 00 00 85 c9 0f 94 c1 83 fa 30 40 0f 93 c6 40 20 ce <40> 80 fe 01 0f 84 30 01 00 00 44 89 74 24 1c 89 6c 24 10 44 8b b4 RSP: 0018:ffffc90000007b70 EFLAGS: 00000046 RAX: ffffffff93172b78 RBX: ffff8880b8827ad8 RCX: 0000000000000001 RDX: 0000000000000002 RSI: 0000000000000000 RDI: ffff88807b70bc80 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000001 R10: dffffc0000000000 R11: fffffbfff1ef9a8f R12: 0000000000000000 R13: ffff8880b8827ad8 R14: 0000000000000000 R15: 0000000000000000 FS: 00007fcce95686c0(0000) GS:ffff88812613e000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fcce89a8000 CR3: 0000000074f38000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0xa2/0xf0 kernel/locking/spinlock.c:170 __run_hrtimer kernel/time/hrtimer.c:1781 [inline] __hrtimer_run_queues+0x602/0xc60 kernel/time/hrtimer.c:1841 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline] __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1058 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa8/0x110 kernel/locking/spinlock.c:194 Code: 74 05 e8 5b 1c 7f f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 53 4a 47 f6 65 8b 05 dc 78 25 07 85 c0 74 40 48 c7 04 24 0e 36 RSP: 0018:ffffc90004596e00 EFLAGS: 00000206 RAX: b02afcbf0d11ab00 RBX: 0000000000000a06 RCX: b02afcbf0d11ab00 RDX: 0000000000000002 RSI: ffffffff8d70bf53 RDI: 0000000000000001 RBP: ffffc90004596e90 R08: ffffffff8f7cd477 R09: 1ffffffff1ef9a8e R10: dffffc0000000000 R11: fffffbfff1ef9a8f R12: dffffc0000000000 R13: dffffc0000000000 R14: ffff8880241ee2e8 R15: 1ffff920008b2dc0 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] taprio_change+0x302c/0x3c40 net/sched/sch_taprio.c:1985 taprio_init+0x959/0xbd0 net/sched/sch_taprio.c:2125 qdisc_create+0x7ac/0xea0 net/sched/sch_api.c:1319 __tc_modify_qdisc net/sched/sch_api.c:1748 [inline] tc_modify_qdisc+0x1538/0x20e0 net/sched/sch_api.c:1812 rtnetlink_rcv_msg+0x77c/0xb70 net/core/rtnetlink.c:6960 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:742 ____sys_sendmsg+0x505/0x830 net/socket.c:2630 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2684 __sys_sendmsg net/socket.c:2716 [inline] __do_sys_sendmsg net/socket.c:2721 [inline] __se_sys_sendmsg net/socket.c:2719 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2719 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcce887dda9 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:00007fcce95680c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fcce89abf80 RCX: 00007fcce887dda9 RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000004 RBP: 00007fcce88ca47a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fcce89abf80 R15: 00007ffde5159748 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g10517 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=3058 rcu: rcu_preempt kthread starved for 10502 jiffies! g10517 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27272 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245