rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (2 ticks this GP) idle=d5f/1/0x4000000000000000 softirq=10563/10564 fqs=1 (detected by 1, t=10504 jiffies, g=13973, q=96) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5421 Comm: syz.2.369 Not tainted 5.15.189-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:__kasan_check_read+0x6/0x10 mm/kasan/shadow.c:31 Code: 41 5f 5d c3 48 c7 c7 57 57 b8 8b eb 0a 48 c7 c7 fc 68 a2 8b 48 89 de e8 18 86 e1 07 31 ed eb d7 00 00 cc cc 89 f6 48 8b 0c 24 <31> d2 e9 43 ef ff ff 0f 1f 00 89 f6 48 8b 0c 24 ba 01 00 00 00 e9 RSP: 0018:ffffc900000078b8 EFLAGS: 00000002 RAX: 0000000000000000 RBX: 0000000000000b5d RCX: ffffffff815bffcb RDX: 0000000000000b5d RSI: 0000000000000008 RDI: ffffffff8ffb7228 RBP: ffffc90000007b10 R08: dffffc0000000000 R09: 0000000000000001 R10: fffffbfff1ad2dd6 R11: 1ffffffff1ad2dd5 R12: ffff88802ba28b60 R13: 0000000000000168 R14: 0000000000000000 R15: ffff88802ba28b40 FS: 00007fadb982d6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c2c970e CR3: 000000005718b000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read include/linux/instrumented.h:71 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] hlock_class kernel/locking/lockdep.c:197 [inline] check_wait_context kernel/locking/lockdep.c:4686 [inline] __lock_acquire+0x51b/0x7c60 kernel/locking/lockdep.c:4962 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:363 [inline] advance_sched+0x47/0x940 net/sched/sch_taprio.c:716 __run_hrtimer kernel/time/hrtimer.c:1690 [inline] __hrtimer_run_queues+0x53d/0xc40 kernel/time/hrtimer.c:1754 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa5/0x100 kernel/locking/spinlock.c:194 Code: 74 05 e8 2e 47 cc f7 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 f6 d4 9f f7 65 8b 05 97 d4 50 76 85 c0 74 3c 48 c7 04 24 0e 36 RSP: 0018:ffffc9000350ee00 EFLAGS: 00000206 RAX: b61428b6880f2300 RBX: 0000000000000a06 RCX: b61428b6880f2300 RDX: dffffc0000000000 RSI: ffffffff8a0b15c0 RDI: 0000000000000001 RBP: ffffc9000350ee90 R08: dffffc0000000000 R09: fffffbfff1ff6e32 R10: fffffbfff1ff6e32 R11: 1ffffffff1ff6e31 R12: dffffc0000000000 R13: 000000246581974e R14: ffff888074a892e8 R15: 1ffff920006a1dc0 spin_unlock_irqrestore include/linux/spinlock.h:418 [inline] taprio_change+0x3ff2/0x4ed0 net/sched/sch_taprio.c:1620 qdisc_create+0x7bd/0x1170 net/sched/sch_api.c:1265 tc_modify_qdisc+0xaa1/0x1770 net/sched/sch_api.c:-1 rtnetlink_rcv_msg+0x9b9/0xe60 net/core/rtnetlink.c:5650 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2507 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8ab/0xbc0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] ____sys_sendmsg+0x5a2/0x8c0 net/socket.c:2436 ___sys_sendmsg+0x1f0/0x260 net/socket.c:2490 __sys_sendmsg net/socket.c:2519 [inline] __do_sys_sendmsg net/socket.c:2528 [inline] __se_sys_sendmsg+0x190/0x250 net/socket.c:2526 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fadbb9c5b69 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:00007fadb982d038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fadbbbecfa0 RCX: 00007fadbb9c5b69 RDX: 0000000000000000 RSI: 00002000000007c0 RDI: 0000000000000005 RBP: 00007fadbba48df1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fadbbbecfa0 R15: 00007ffff9e2ec28 rcu: rcu_preempt kthread starved for 10497 jiffies! g13973 f0x0 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:27168 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376 schedule+0x11b/0x1e0 kernel/sched/core.c:6459 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 1 CPU: 1 PID: 5411 Comm: syz.0.368 Not tainted 5.15.189-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline] rcu_check_gp_kthread_starvation+0x1cd/0x250 kernel/rcu/tree_stall.h:487 print_other_cpu_stall+0x10c8/0x1220 kernel/rcu/tree_stall.h:592 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline] rcu_pending kernel/rcu/tree.c:3936 [inline] rcu_sched_clock_irq+0x831/0x1110 kernel/rcu/tree.c:2619 update_process_times+0x193/0x200 kernel/time/timer.c:1818 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1690 [inline] __hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1754 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline] RIP: 0010:smp_call_function_many_cond+0xb88/0xd70 kernel/smp.c:969 Code: b6 44 05 00 84 c0 0f 85 9d 00 00 00 41 8b 1c 24 89 de 83 e6 01 31 ff e8 a6 46 0b 00 83 e3 01 75 07 e8 3c 43 0b 00 eb 43 f3 90 <48> b8 00 00 00 00 00 fc ff df 41 0f b6 44 05 00 84 c0 75 11 41 f7 RSP: 0018:ffffc9000135fa00 EFLAGS: 00000293 RAX: ffffffff816c810b RBX: 0000000000000001 RCX: ffff88802c335940 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000135fb40 R08: dffffc0000000000 R09: fffffbfff1ff6e19 R10: fffffbfff1ff6e19 R11: 1ffffffff1ff6e18 R12: ffff8880b9042a08 R13: 1ffff11017208541 R14: ffff8880b913b380 R15: 0000000000000000 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1135 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1442 [inline] text_poke_bp_batch+0x2a9/0x7c0 arch/x86/kernel/alternative.c:1642 text_poke_flush arch/x86/kernel/alternative.c:1833 [inline] text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1840 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146 static_key_disable_cpuslocked+0xbd/0x1a0 kernel/jump_label.c:207 static_key_disable+0x16/0x20 kernel/jump_label.c:215 tracepoint_remove_func kernel/tracepoint.c:417 [inline] tracepoint_probe_unregister+0x6a9/0x930 kernel/tracepoint.c:551 bpf_raw_tp_link_release+0x5f/0x80 kernel/bpf/syscall.c:2900 bpf_link_free kernel/bpf/syscall.c:2466 [inline] bpf_link_put+0x22a/0x2c0 kernel/bpf/syscall.c:2492 bpf_link_release+0x37/0x40 kernel/bpf/syscall.c:2500 __fput+0x234/0x930 fs/file_table.c:311 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f8e4f291b69 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:00007ffc915a5da8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f8e4f4baba0 RCX: 00007f8e4f291b69 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f8e4f4baba0 R08: 0000000000000104 R09: 0000000e915a609f R10: 00007f8e4f4baac0 R11: 0000000000000246 R12: 00000000000262f3 R13: 00007f8e4f4b9080 R14: ffffffffffffffff R15: 00007ffc915a5ec0