rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (1 GPs behind) idle=a464/1/0x4000000000000000 softirq=9285/9286 fqs=13 rcu: (t=10500 jiffies g=9801 q=850 ncpus=2) rcu: rcu_preempt kthread starved for 10466 jiffies! g9801 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:28256 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0xee1/0x59f0 kernel/sched/core.c:6710 schedule+0xe7/0x1b0 kernel/sched/core.c:6786 schedule_timeout+0x157/0x2c0 kernel/time/timer.c:2167 rcu_gp_fqs_loop+0x1ec/0xa50 kernel/rcu/tree.c:1609 rcu_gp_kthread+0x249/0x380 kernel/rcu/tree.c:1808 kthread+0x33a/0x430 kernel/kthread.c:389 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 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: 4768 Comm: kworker/1:3 Not tainted 6.5.0-rc1-syzkaller-00178-g8fcd7c7b3a38 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023 Workqueue: wg-crypt-wg0 wg_packet_encrypt_worker RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:200 Code: 96 e8 98 02 66 0f 1f 44 00 00 f3 0f 1e fa 48 8b be b0 01 00 00 e8 b0 ff ff ff 31 c0 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 0f 1e fa 65 8b 05 dd 4a 7d 7e 89 c1 48 8b 34 24 81 e1 00 01 00 RSP: 0018:ffffc900001e0bc8 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000002af31dc RCX: ffffffff88584256 RDX: ffff888022058000 RSI: 0000000000000100 RDI: 0000000000000006 RBP: 000000a7c5ac471b R08: 0000000000000006 R09: 0000000000000000 R10: 000000a7c5ac471b R11: ffffc900001e0ff8 R12: 00000000000186a0 R13: 0000000000000003 R14: 000000000044b82f R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000080 CR3: 0000000079711000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: pie_calculate_probability+0x2a0/0x850 net/sched/sch_pie.c:345 fq_pie_timer+0x1da/0x4f0 net/sched/sch_fq_pie.c:387 call_timer_fn+0x1a0/0x580 kernel/time/timer.c:1700 expire_timers kernel/time/timer.c:1751 [inline] __run_timers+0x764/0xb10 kernel/time/timer.c:2022 run_timer_softirq+0x58/0xd0 kernel/time/timer.c:2035 __do_softirq+0x218/0x965 kernel/softirq.c:553 do_softirq kernel/softirq.c:454 [inline] do_softirq+0xaa/0xe0 kernel/softirq.c:441 __local_bh_enable_ip+0xf8/0x120 kernel/softirq.c:381 spin_unlock_bh include/linux/spinlock.h:396 [inline] ptr_ring_consume_bh include/linux/ptr_ring.h:367 [inline] wg_packet_encrypt_worker+0x27e/0xbb0 drivers/net/wireguard/send.c:293 process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2597 worker_thread+0x687/0x1110 kernel/workqueue.c:2748 kthread+0x33a/0x430 kernel/kthread.c:389 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 CPU: 0 PID: 5188 Comm: syz-executor166 Not tainted 6.5.0-rc1-syzkaller-00178-g8fcd7c7b3a38 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023 RIP: 0010:pie_calculate_probability+0x287/0x850 net/sched/sch_pie.c:345 Code: 89 6c 24 38 e8 7a 2c 2e f9 47 8d 24 a4 31 d2 4c 89 ff 43 8d 0c 24 49 c1 ee 02 48 b8 ff ff ff ff ff ff ff 00 48 f7 f1 48 89 c5 <48> 89 c6 48 c1 eb 02 49 89 cc e8 5a 27 2e f9 49 39 ef 73 18 e8 40 RSP: 0018:ffffc90000007bc0 EFLAGS: 00000203 RAX: 00000010c6f7a0b5 RBX: 0000000002af31dc RCX: 00000000000f4240 RDX: 00000000000e28bf RSI: ffffffff88584226 RDI: 0000000000000000 RBP: 00000010c6f7a0b5 R08: 0000000000000005 R09: 00000000000f4240 R10: 00000000000186a0 R11: 0000000000094000 R12: 000000000007a120 R13: 0000000000000002 R14: 0000000000112e0b R15: 0000000000000000 FS: 0000555556f03380(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000080 CR3: 00000000666a3000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: fq_pie_timer+0x1da/0x4f0 net/sched/sch_fq_pie.c:387 call_timer_fn+0x1a0/0x580 kernel/time/timer.c:1700 expire_timers kernel/time/timer.c:1751 [inline] __run_timers+0x764/0xb10 kernel/time/timer.c:2022 run_timer_softirq+0x58/0xd0 kernel/time/timer.c:2035 __do_softirq+0x218/0x965 kernel/softirq.c:553 invoke_softirq kernel/softirq.c:427 [inline] __irq_exit_rcu kernel/softirq.c:632 [inline] irq_exit_rcu+0xb7/0x120 kernel/softirq.c:644 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1109 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x70 kernel/locking/spinlock.c:194 Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 56 e9 31 f7 48 89 df e8 0e 62 32 f7 f7 c5 00 02 00 00 75 1f 9c 58 f6 c4 02 75 2f 01 00 00 00 e8 85 0d 24 f7 65 8b 05 a6 2b ce 75 85 c0 74 12 5b RSP: 0018:ffffc9000317f280 EFLAGS: 00000246 RAX: 0000000000000002 RBX: ffff88813fffacc0 RCX: 1ffffffff2309856 RDX: 0000000000000000 RSI: ffffffff8a6c7720 RDI: ffffffff8ac804c0 RBP: 0000000000000297 R08: 0000000000000001 R09: fffffbfff23093d0 R10: ffffffff91849e87 R11: dffffc0000000000 R12: 000000000005c605 R13: 0000000000000000 R14: 0000000000000700 R15: ffff88813fffa000 free_unref_page+0x1c5/0x3b0 mm/page_alloc.c:2466 vfree+0x181/0x7a0 mm/vmalloc.c:2842 kvfree+0x33/0x50 mm/util.c:648 __qdisc_destroy+0xc4/0x450 net/sched/sch_generic.c:1063 qdisc_put+0xd1/0xf0 net/sched/sch_generic.c:1090 notify_and_destroy net/sched/sch_api.c:1047 [inline] qdisc_graft+0x1122/0x1680 net/sched/sch_api.c:1144 tc_modify_qdisc+0xcd2/0x1bf0 net/sched/sch_api.c:1731 rtnetlink_rcv_msg+0x439/0xd30 net/core/rtnetlink.c:6424 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2549 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x539/0x800 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x93c/0xe30 net/netlink/af_netlink.c:1914 sock_sendmsg_nosec net/socket.c:725 [inline] sock_sendmsg+0xd9/0x180 net/socket.c:748 ____sys_sendmsg+0x6ac/0x940 net/socket.c:2494 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2548 __sys_sendmsg+0x117/0x1e0 net/socket.c:2577 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f84a80b6e99 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 11 1d 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:00007ffc8a5a6338 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f84a80b6e99 RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000003 RBP: 00000000000f4240 R08: 00007ffc8a5a6430 R09: 00007ffc8a5a6430 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc8a5a63e8 R13: 00007f84a812db40 R14: 00007f84a812fd00 R15: 00007ffc8a5a6420