rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=3b14/1/0x4000000000000000 softirq=38182/38183 fqs=0 rcu: (detected by 0, t=10502 jiffies, g=33893, q=260 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 10648 Comm: syz.6.1223 Not tainted 6.14.0-rc5-syzkaller-00013-g99fa936e8e4f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:instrument_atomic_read_write include/linux/instrumented.h:96 [inline] RIP: 0010:atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1300 [inline] RIP: 0010:queued_spin_lock include/asm-generic/qspinlock.h:111 [inline] RIP: 0010:do_raw_spin_lock+0x119/0x2c0 kernel/locking/spinlock_debug.c:116 Code: 84 d2 0f 85 68 01 00 00 8b 53 08 65 8b 05 3b bb 6c 7e 39 c2 0f 84 35 01 00 00 48 89 df be 04 00 00 00 c7 44 24 28 00 00 00 00 c2 e4 85 00 be 04 00 00 00 48 8d 7c 24 28 e8 b3 e4 85 00 8b 44 RSP: 0018:ffffc90000a18d98 EFLAGS: 00000082 RAX: 0000000000000001 RBX: ffff8880b872c680 RCX: ffffffff8195b7be RDX: 00000000ffffffff RSI: 0000000000000004 RDI: ffff8880b872c680 RBP: 1ffff920001431b4 R08: 0000000000000000 R09: fffffbfff2dd8599 R10: ffffffff96ec2ccf R11: 0000000000000002 R12: ffff8880b872c688 R13: ffff8880b872c690 R14: ffff8880b872c680 R15: ffffffff896a9820 FS: 00007f17d005b6c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c292a02 CR3: 000000005d8de000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __run_hrtimer kernel/time/hrtimer.c:1805 [inline] __hrtimer_run_queues+0x2be/0xae0 kernel/time/hrtimer.c:1865 hrtimer_interrupt+0x392/0x8e0 kernel/time/hrtimer.c:1927 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x10f/0x400 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049 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 96 dc 3c f6 48 89 df e8 ee 5b 3d f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 65 31 2e f6 65 8b 05 a6 13 aa 74 85 c0 74 16 5b RSP: 0018:ffffc9000374f108 EFLAGS: 00000246 RAX: 0000000000000006 RBX: ffff8880345362e8 RCX: 1ffffffff2dee7c5 RDX: 0000000000000000 RSI: ffffffff8b6cee00 RDI: ffffffff8bd35aa0 RBP: 0000000000000246 R08: 0000000000000001 R09: fffffbfff2dd85d0 R10: ffffffff96ec2e87 R11: 0000000000000004 R12: 0000000000000246 R13: 0000000000000001 R14: 00000062996883a8 R15: 0000000000000001 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] taprio_change+0x28ef/0x3a80 net/sched/sch_taprio.c:1973 taprio_init+0x6b0/0x940 net/sched/sch_taprio.c:2114 qdisc_create+0x4f1/0x1100 net/sched/sch_api.c:1360 tc_modify_qdisc+0x4d8/0x1d30 net/sched/sch_api.c:1786 rtnetlink_rcv_msg+0x3c7/0xea0 net/core/rtnetlink.c:6921 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2533 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline] netlink_unicast+0x53c/0x7f0 net/netlink/af_netlink.c:1338 netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1882 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:733 [inline] ____sys_sendmsg+0xaaf/0xc90 net/socket.c:2573 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2627 __sys_sendmsg+0x16e/0x220 net/socket.c:2659 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f17cf18d169 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f17d005b038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f17cf3a5fa0 RCX: 00007f17cf18d169 RDX: 0000000000000000 RSI: 00004000000007c0 RDI: 0000000000000003 RBP: 00007f17cf20e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f17cf3a5fa0 R15: 00007ffd388f2488 rcu: rcu_preempt kthread starved for 10502 jiffies! g33893 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:26848 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6857 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2024 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2226 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 UID: 0 PID: 10626 Comm: syz.2.1215 Not tainted 6.14.0-rc5-syzkaller-00013-g99fa936e8e4f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x4c6/0x12c0 kernel/smp.c:885 Code: 0c 00 85 ed 74 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 fc 4c 89 fd 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 7c 0e 0c 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 e8 0b 00 00 8b 43 08 31 RSP: 0018:ffffc900052af5a0 EFLAGS: 00000246 RAX: 0000000000080000 RBX: ffff8880b8744a80 RCX: ffffc9000c079000 RDX: 0000000000080000 RSI: ffffffff81add344 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000005 R12: ffffed10170e8951 R13: 0000000000000001 R14: ffff8880b863fe80 R15: ffff8880b8744a88 FS: 00007ffbfebcd6c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2f60bff8 CR3: 00000000584e8000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1052 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2118 [inline] text_poke_bp_batch+0x22b/0x760 arch/x86/kernel/alternative.c:2328 text_poke_bp+0xa3/0xd0 arch/x86/kernel/alternative.c:2555 __static_call_transform+0x34d/0x770 arch/x86/kernel/static_call.c:111 arch_static_call_transform+0x5d/0xb0 arch/x86/kernel/static_call.c:163 __static_call_update+0xee/0x660 kernel/static_call_inline.c:147 tracepoint_update_call kernel/tracepoint.c:271 [inline] tracepoint_add_func+0xa90/0xeb0 kernel/tracepoint.c:312 tracepoint_probe_register_prio_may_exist+0xbd/0x110 kernel/tracepoint.c:435 tracepoint_probe_register_may_exist include/linux/tracepoint.h:50 [inline] bpf_probe_register+0x189/0x200 kernel/trace/bpf_trace.c:2439 bpf_raw_tp_link_attach+0x2cd/0x5f0 kernel/bpf/syscall.c:3986 bpf_raw_tracepoint_open kernel/bpf/syscall.c:4017 [inline] __sys_bpf+0x3a4/0x49c0 kernel/bpf/syscall.c:5837 __do_sys_bpf kernel/bpf/syscall.c:5902 [inline] __se_sys_bpf kernel/bpf/syscall.c:5900 [inline] __x64_sys_bpf+0x78/0xc0 kernel/bpf/syscall.c:5900 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ffbfdd8d169 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffbfebcd038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007ffbfdfa5fa0 RCX: 00007ffbfdd8d169 RDX: 0000000000000018 RSI: 00004000000000c0 RDI: 0000000000000011 RBP: 00007ffbfde0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ffbfdfa5fa0 R15: 00007ffe4eb46af8