TCP: request_sock_subflow_v4: Possible SYN flooding on port [::]:20002. Sending cookies. rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=31ec/1/0x4000000000000000 softirq=167247/167266 fqs=1 rcu: (detected by 0, t=10502 jiffies, g=229373, q=769 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 27308 Comm: syz.2.6068 Not tainted 6.11.0-rc1-next-20240729-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:200 Code: 89 fb e8 23 00 00 00 48 8b 3d ac b7 95 0c 48 89 de 5b e9 d3 d2 5b 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 40 d7 03 00 65 8b 15 d0 0b RSP: 0018:ffffc90000a18d20 EFLAGS: 00000002 RAX: 0000000000010203 RBX: 0000000000000001 RCX: ffff888011d83c00 RDX: ffff888011d83c00 RSI: ffff88804736e340 RDI: ffff8880b932c9d0 RBP: dffffc0000000000 R08: ffffffff818111f2 R09: 1ffffffff202faed R10: dffffc0000000000 R11: fffffbfff202faee R12: 1ffff1101726593b R13: ffff88804736e340 R14: ffff8880b932c9d0 R15: ffff8880b932c880 FS: 00007fbaaf8206c0(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1c1711a000 CR3: 0000000046820000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: timerqueue_del+0x23/0x100 lib/timerqueue.c:54 __remove_hrtimer kernel/time/hrtimer.c:1118 [inline] __run_hrtimer kernel/time/hrtimer.c:1669 [inline] __hrtimer_run_queues+0x3d0/0xd50 kernel/time/hrtimer.c:1753 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1815 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 ae 9f 37 f6 f6 44 24 21 02 75 52 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 03 30 9f f5 65 8b 05 44 26 40 74 85 c0 74 43 48 c7 04 24 0e 36 RSP: 0018:ffffc9000a5c6de0 EFLAGS: 00000206 RAX: 5c6379272718bc00 RBX: 1ffff920014b8dc0 RCX: ffffffff817022ea RDX: dffffc0000000000 RSI: ffffffff8c0ad560 RDI: 0000000000000001 RBP: ffffc9000a5c6e70 R08: ffffffff93737a17 R09: 1ffffffff26e6f42 R10: dffffc0000000000 R11: fffffbfff26e6f43 R12: dffffc0000000000 R13: 1ffff920014b8dbc R14: ffffc9000a5c6e00 R15: 0000000000000246 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] taprio_change+0x270d/0x4430 net/sched/sch_taprio.c:1970 taprio_init+0x9da/0xc80 net/sched/sch_taprio.c:2111 qdisc_create+0x9d4/0x11a0 net/sched/sch_api.c:1355 tc_modify_qdisc+0xa26/0x1e40 net/sched/sch_api.c:1777 rtnetlink_rcv_msg+0x744/0xd00 net/core/rtnetlink.c:6734 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2550 netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline] netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1357 netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1901 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2597 ___sys_sendmsg net/socket.c:2651 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2680 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fbaae9773b9 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:00007fbaaf820048 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fbaaeb05f80 RCX: 00007fbaae9773b9 RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000005 RBP: 00007fbaae9e48e6 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fbaaeb05f80 R15: 00007ffcc7575de8 rcu: rcu_preempt kthread starved for 10496 jiffies! g229373 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:24824 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5239 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6603 __schedule_loop kernel/sched/core.c:6680 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6695 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2034 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2236 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:144 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: 12 Comm: kworker/u8:1 Not tainted 6.11.0-rc1-next-20240729-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:312 [inline] RIP: 0010:smp_call_function_many_cond+0x1860/0x29d0 kernel/smp.c:856 Code: 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 49 15 0c 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 f4 10 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 d8 10 RSP: 0018:ffffc90000117700 EFLAGS: 00000293 RAX: ffffffff8187ba88 RBX: 1ffff110172688f9 RCX: ffff888017ad5a00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900001178e0 R08: ffffffff8187ba57 R09: 1ffffffff26e6f00 R10: dffffc0000000000 R11: fffffbfff26e6f01 R12: dffffc0000000000 R13: ffff8880b93447c8 R14: ffff8880b923fb80 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005555738fb808 CR3: 000000000e734000 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:2085 [inline] text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2295 text_poke_flush arch/x86/kernel/alternative.c:2486 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2493 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x136/0x260 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xb5/0x250 mm/kfence/core.c:833 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:144 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 DEBUG: holding rtnl_mutex for 11507 jiffies. task:syz.2.6068 state:R running task stack:25232 pid:27308 tgid:27307 ppid:26720 flags:0x0000400e Call Trace: sched_show_task+0x506/0x6d0 kernel/sched/core.c:7512