rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-....: (9199 ticks this GP) idle=e1ac/1/0x4000000000000000 softirq=38481/38483 fqs=3998 rcu: hardirqs softirqs csw/system rcu: number: 1525792 5 0 rcu: cputime: 13408 39070 46 ==> 52480(ms) rcu: (t=10500 jiffies g=42421 q=1559 ncpus=2) CPU: 1 PID: 11119 Comm: syz.2.1889 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x2e/0x60 kernel/kcov.c:216 Code: 48 8b 04 24 65 48 8b 0d c0 d2 7c 7e 65 8b 15 c1 d2 7c 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 1c 16 00 00 00 <74> 2c 8b 91 f8 15 00 00 83 fa 02 75 21 48 8b 91 00 16 00 00 48 8b RSP: 0018:ffffc900001ef090 EFLAGS: 00000246 RAX: ffffffff813b2a4c RBX: ffffffff8f102272 RCX: ffff88802ba33c00 RDX: 0000000000000100 RSI: ffffffff8cfa05a0 RDI: 0000000000000002 RBP: ffffc900001ef1b8 R08: ffff88802ba33c00 R09: 0000000000000002 R10: 0000000000000001 R11: 0000000000000100 R12: ffffffff8f102277 R13: ffffc900001ef168 R14: 0000000000000002 R15: dffffc0000000000 FS: 00007f5d0f4e06c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4f35deb540 CR3: 000000005cc22000 CR4: 00000000003506e0 DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: unwind_next_frame+0x67c/0x2990 arch/x86/kernel/unwind_orc.c:505 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6a/0x4d0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc+0x17e/0x2c0 mm/slub.c:3519 skb_clone+0x1eb/0x370 net/core/skbuff.c:1912 dev_queue_xmit_nit+0x23f/0xba0 net/core/dev.c:2353 xmit_one net/core/dev.c:3640 [inline] dev_hard_start_xmit+0x150/0x790 net/core/dev.c:3660 sch_direct_xmit+0x251/0x4a0 net/sched/sch_generic.c:345 __dev_xmit_skb net/core/dev.c:3881 [inline] __dev_queue_xmit+0x162a/0x3630 net/core/dev.c:4416 dev_queue_xmit include/linux/netdevice.h:3113 [inline] neigh_hh_output include/net/neighbour.h:527 [inline] neigh_output include/net/neighbour.h:541 [inline] ip_finish_output2+0xd4f/0x1260 net/ipv4/ip_output.c:235 NF_HOOK_COND include/linux/netfilter.h:293 [inline] ip_output+0x2a5/0x3a0 net/ipv4/ip_output.c:436 dst_output include/net/dst.h:467 [inline] ip_local_out net/ipv4/ip_output.c:129 [inline] __ip_queue_xmit+0x1056/0x1960 net/ipv4/ip_output.c:540 __tcp_transmit_skb+0x1dd6/0x3470 net/ipv4/tcp_output.c:1427 tcp_validate_incoming+0xf37/0x22b0 net/ipv4/tcp_input.c:5901 tcp_rcv_established+0x7e1/0x1d70 net/ipv4/tcp_input.c:6166 tcp_v4_do_rcv+0x6d3/0xba0 net/ipv4/tcp_ipv4.c:1735 tcp_v4_rcv+0x2358/0x2a60 net/ipv4/tcp_ipv4.c:2167 ip_protocol_deliver_rcu+0x20a/0x3f0 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x2c3/0x510 net/ipv4/ip_input.c:233 NF_HOOK+0x32d/0x3b0 include/linux/netfilter.h:304 dst_input include/net/dst.h:477 [inline] ip_sublist_rcv_finish net/ipv4/ip_input.c:580 [inline] ip_list_rcv_finish net/ipv4/ip_input.c:631 [inline] ip_sublist_rcv+0xa36/0xd60 net/ipv4/ip_input.c:639 ip_list_rcv+0x3ed/0x440 net/ipv4/ip_input.c:674 __netif_receive_skb_list_ptype net/core/dev.c:5689 [inline] __netif_receive_skb_list_core+0x582/0x770 net/core/dev.c:5737 __netif_receive_skb_list net/core/dev.c:5789 [inline] netif_receive_skb_list_internal+0x943/0xca0 net/core/dev.c:5880 gro_normal_list include/net/gro.h:451 [inline] napi_complete_done+0x329/0x820 net/core/dev.c:6220 virtqueue_napi_complete drivers/net/virtio_net.c:450 [inline] virtnet_poll+0xaa0/0x11e0 drivers/net/virtio_net.c:2236 __napi_poll+0xbb/0x460 net/core/dev.c:6650 napi_poll net/core/dev.c:6717 [inline] net_rx_action+0x65f/0xcc0 net/core/dev.c:6853 handle_softirqs+0x27d/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:finish_task_switch+0x267/0x8f0 kernel/sched/core.c:5255 Code: 2e 09 85 c0 0f 84 30 01 00 00 48 85 db 0f 85 4f 01 00 00 0f 1f 44 00 00 4c 89 e7 e8 43 32 38 09 e8 8e 0a 30 00 fb 4c 8b 65 b8 <49> 8d bc 24 f8 15 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 RSP: 0018:ffffc9001922f5c0 EFLAGS: 00000282 RAX: 655388ad7227f200 RBX: 0000000000000000 RCX: 655388ad7227f200 RDX: dffffc0000000000 RSI: ffffffff8acacb60 RDI: ffffffff8b1cfa20 RBP: ffffc9001922f610 R08: ffffffff8e8c6b2f R09: 1ffffffff1d18d65 R10: dffffc0000000000 R11: fffffbfff1d18d66 R12: ffff88802ba33c00 R13: 1ffff110171e79a9 R14: dffffc0000000000 R15: ffff8880b8f3cd48 context_switch kernel/sched/core.c:5384 [inline] __schedule+0x15b6/0x4660 kernel/sched/core.c:6700 preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6867 preempt_schedule+0xc0/0xd0 kernel/sched/core.c:6891 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] _raw_spin_unlock_irq+0x40/0x50 kernel/locking/spinlock.c:202 spin_unlock_irq include/linux/spinlock.h:401 [inline] acct_collect+0x5ba/0x780 kernel/acct.c:624 do_exit+0x88f/0x2530 kernel/exit.c:854 do_group_exit+0x22d/0x2f0 kernel/exit.c:1026 get_signal+0x12a6/0x1390 kernel/signal.c:2903 arch_do_signal_or_restart+0xc2/0x7b0 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f5d0e59de59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f5d0f4e0028 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: 0000000000000005 RBX: 00007f5d0e825fa0 RCX: 00007f5d0e59de59 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000140 RBP: 00007f5d0e633e6f R08: 0000000000000002 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007f5d0e826038 R14: 00007f5d0e825fa0 R15: 00007ffdcacab938