rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (10501 ticks this GP) idle=ac3/1/0x4000000000000000 softirq=45593/45593 fqs=0 (t=10502 jiffies g=78061 q=1559) rcu: rcu_preempt kthread timer wakeup didn't happen for 10502 jiffies! g78061 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=23143 rcu: rcu_preempt kthread starved for 10505 jiffies! g78061 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:28000 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4969 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6250 schedule+0xd2/0x260 kernel/sched/core.c:6323 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1955 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2128 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 0 CPU: 0 PID: 24359 Comm: syz-executor.2 Not tainted 5.15.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_check_gp_kthread_starvation.cold+0x1fb/0x200 kernel/rcu/tree_stall.h:481 print_cpu_stall kernel/rcu/tree_stall.h:625 [inline] check_cpu_stall kernel/rcu/tree_stall.h:711 [inline] rcu_pending kernel/rcu/tree.c:3878 [inline] rcu_sched_clock_irq.cold+0x98/0x746 kernel/rcu/tree.c:2597 update_process_times+0x16d/0x200 kernel/time/timer.c:1785 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1421 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:write_comp_data kernel/kcov.c:221 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x17/0x70 kernel/kcov.c:287 Code: 30 f0 4c 89 54 d8 20 48 89 10 5b c3 0f 1f 80 00 00 00 00 41 89 f8 bf 03 00 00 00 4c 8b 14 24 89 f1 65 48 8b 34 25 40 70 02 00 14 f9 ff ff 84 c0 74 4b 48 8b 86 88 15 00 00 8b b6 84 15 00 00 RSP: 0018:ffffc90015e27550 EFLAGS: 00000246 RAX: 0000000000040000 RBX: 0000000000000bc8 RCX: 0000000000000bc8 RDX: 0000000000040000 RSI: ffff888071fdba00 RDI: 0000000000000003 RBP: 00000000000005e3 R08: 0000000000001fff R09: 0000000000000000 R10: ffffffff875224e1 R11: 0000000000000000 R12: ffff88807c1e02c0 R13: 0000000000000bc7 R14: 0000000000000000 R15: dffffc0000000000 cake_heapify+0x221/0x3d0 net/sched/sch_cake.c:1434 cake_drop net/sched/sch_cake.c:1515 [inline] cake_enqueue+0x13b0/0x3a00 net/sched/sch_cake.c:1903 dev_qdisc_enqueue+0x40/0x300 net/core/dev.c:3785 __dev_xmit_skb net/core/dev.c:3869 [inline] __dev_queue_xmit+0x1f6e/0x3630 net/core/dev.c:4194 __netlink_deliver_tap_skb net/netlink/af_netlink.c:303 [inline] __netlink_deliver_tap net/netlink/af_netlink.c:321 [inline] netlink_deliver_tap+0x9cb/0xc30 net/netlink/af_netlink.c:334 netlink_deliver_tap_kernel net/netlink/af_netlink.c:343 [inline] netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x5e5/0x7d0 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x86d/0xda0 net/netlink/af_netlink.c:1916 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:724 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2409 ___sys_sendmsg+0xf3/0x170 net/socket.c:2463 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2492 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fd391061ae9 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fd38e5d7188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fd391174f60 RCX: 00007fd391061ae9 RDX: 0000000000000000 RSI: 00000000200000c0 RDI: 0000000000000003 RBP: 00007fd3910bbf6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffee4004c9f R14: 00007fd38e5d7300 R15: 0000000000022000 NMI backtrace for cpu 0 CPU: 0 PID: 24359 Comm: syz-executor.2 Not tainted 5.15.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x25e/0x3f0 kernel/rcu/tree_stall.h:343 print_cpu_stall kernel/rcu/tree_stall.h:627 [inline] check_cpu_stall kernel/rcu/tree_stall.h:711 [inline] rcu_pending kernel/rcu/tree.c:3878 [inline] rcu_sched_clock_irq.cold+0x9d/0x746 kernel/rcu/tree.c:2597 update_process_times+0x16d/0x200 kernel/time/timer.c:1785 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1421 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:write_comp_data kernel/kcov.c:221 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x17/0x70 kernel/kcov.c:287 Code: 30 f0 4c 89 54 d8 20 48 89 10 5b c3 0f 1f 80 00 00 00 00 41 89 f8 bf 03 00 00 00 4c 8b 14 24 89 f1 65 48 8b 34 25 40 70 02 00 14 f9 ff ff 84 c0 74 4b 48 8b 86 88 15 00 00 8b b6 84 15 00 00 RSP: 0018:ffffc90015e27550 EFLAGS: 00000246 RAX: 0000000000040000 RBX: 0000000000000bc8 RCX: 0000000000000bc8 RDX: 0000000000040000 RSI: ffff888071fdba00 RDI: 0000000000000003 RBP: 00000000000005e3 R08: 0000000000001fff R09: 0000000000000000 R10: ffffffff875224e1 R11: 0000000000000000 R12: ffff88807c1e02c0 R13: 0000000000000bc7 R14: 0000000000000000 R15: dffffc0000000000 cake_heapify+0x221/0x3d0 net/sched/sch_cake.c:1434 cake_drop net/sched/sch_cake.c:1515 [inline] cake_enqueue+0x13b0/0x3a00 net/sched/sch_cake.c:1903 dev_qdisc_enqueue+0x40/0x300 net/core/dev.c:3785 __dev_xmit_skb net/core/dev.c:3869 [inline] __dev_queue_xmit+0x1f6e/0x3630 net/core/dev.c:4194 __netlink_deliver_tap_skb net/netlink/af_netlink.c:303 [inline] __netlink_deliver_tap net/netlink/af_netlink.c:321 [inline] netlink_deliver_tap+0x9cb/0xc30 net/netlink/af_netlink.c:334 netlink_deliver_tap_kernel net/netlink/af_netlink.c:343 [inline] netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x5e5/0x7d0 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x86d/0xda0 net/netlink/af_netlink.c:1916 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:724 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2409 ___sys_sendmsg+0xf3/0x170 net/socket.c:2463 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2492 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fd391061ae9 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fd38e5d7188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fd391174f60 RCX: 00007fd391061ae9 RDX: 0000000000000000 RSI: 00000000200000c0 RDI: 0000000000000003 RBP: 00007fd3910bbf6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffee4004c9f R14: 00007fd38e5d7300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: 30 f0 xor %dh,%al 2: 4c 89 54 d8 20 mov %r10,0x20(%rax,%rbx,8) 7: 48 89 10 mov %rdx,(%rax) a: 5b pop %rbx b: c3 retq c: 0f 1f 80 00 00 00 00 nopl 0x0(%rax) 13: 41 89 f8 mov %edi,%r8d 16: bf 03 00 00 00 mov $0x3,%edi 1b: 4c 8b 14 24 mov (%rsp),%r10 1f: 89 f1 mov %esi,%ecx 21: 65 48 8b 34 25 40 70 mov %gs:0x27040,%rsi 28: 02 00 * 2a: e8 14 f9 ff ff callq 0xfffff943 <-- trapping instruction 2f: 84 c0 test %al,%al 31: 74 4b je 0x7e 33: 48 8b 86 88 15 00 00 mov 0x1588(%rsi),%rax 3a: 8b b6 84 15 00 00 mov 0x1584(%rsi),%esi