rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 0-....: (10500 ticks this GP) idle=a7ac/1/0x4000000000000000 softirq=19839/19839 fqs=5169
rcu: hardirqs softirqs csw/system
rcu: number: 1166504 0 0
rcu: cputime: 18645 33834 70 ==> 52500(ms)
rcu: (t=10502 jiffies g=23893 q=1709 ncpus=2)
CPU: 0 PID: 7674 Comm: syz.2.489 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:245 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x1f/0x90 kernel/kcov.c:313
Code: 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 48 8b 04 24 65 48 8b 15 60 9e 7c 7e 65 8b 0d 61 9e 7c 7e 81 e1 00 01 ff 00 74 11 <81> f9 00 01 00 00 75 5b 83 ba 1c 16 00 00 00 74 52 8b 8a f8 15 00
RSP: 0018:ffffc90000006e10 EFLAGS: 00000206
RAX: ffffffff813b62e3 RBX: 1ffff92000000de9 RCX: 0000000000000100
RDX: ffff888022725a00 RSI: 0000000000000002 RDI: 0000000000000000
RBP: 0000000000000002 R08: ffff888022725a00 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000000100 R12: ffffc90000008000
R13: 1ffff92000000deb R14: ffffc90000000000 R15: ffffc90000006f48
FS: 00007fca46fb26c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000024acd000 CR4: 00000000003506f0
DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
on_stack arch/x86/include/asm/stacktrace.h:58 [inline]
stack_access_ok arch/x86/kernel/unwind_orc.c:393 [inline]
deref_stack_reg+0x93/0x240 arch/x86/kernel/unwind_orc.c:403
unwind_next_frame+0x1789/0x2970 arch/x86/kernel/unwind_orc.c:648
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_save_free_info+0x2e/0x50 mm/kasan/generic.c:522
____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:237
kasan_slab_free include/linux/kasan.h:164 [inline]
slab_free_hook mm/slub.c:1811 [inline]
slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837
slab_free mm/slub.c:3830 [inline]
kmem_cache_free+0xf8/0x270 mm/slub.c:3852
skb_kfree_head net/core/skbuff.c:947 [inline]
skb_free_head net/core/skbuff.c:961 [inline]
skb_release_data+0x60a/0x800 net/core/skbuff.c:991
skb_release_all net/core/skbuff.c:1057 [inline]
__kfree_skb net/core/skbuff.c:1071 [inline]
consume_skb+0xb2/0x110 net/core/skbuff.c:1287
dummy_xmit+0x137/0x1c0 drivers/net/dummy.c:64
__netdev_start_xmit include/linux/netdevice.h:4943 [inline]
netdev_start_xmit include/linux/netdevice.h:4957 [inline]
xmit_one net/core/dev.c:3632 [inline]
dev_hard_start_xmit+0x246/0x740 net/core/dev.c:3648
__dev_queue_xmit+0x1ac2/0x36b0 net/core/dev.c:4438
neigh_output include/net/neighbour.h:543 [inline]
ip6_finish_output2+0xe3d/0x1630 net/ipv6/ip6_output.c:141
dst_output include/net/dst.h:467 [inline]
NF_HOOK include/linux/netfilter.h:304 [inline]
ndisc_send_skb+0xc26/0x14f0 net/ipv6/ndisc.c:513
addrconf_rs_timer+0x2d5/0x630 net/ipv6/addrconf.c:4024
call_timer_fn+0x189/0x540 kernel/time/timer.c:1701
expire_timers kernel/time/timer.c:1752 [inline]
__run_timers+0x542/0x800 kernel/time/timer.c:2023
run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2036
handle_softirqs+0x280/0x820 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:generic_exec_single+0x481/0x4f0 kernel/smp.c:418
Code: 75 11 e8 02 02 0b 00 48 85 db 75 16 e8 f8 01 0b 00 eb 15 e8 f1 01 0b 00 e8 cc 4a 08 09 48 85 db 74 ea e8 e2 01 0b 00 fb 31 c0 <48> c7 44 24 20 0e 36 e0 45 4b c7 04 2c 00 00 00 00 43 c7 44 2c 08
RSP: 0018:ffffc9000be4fa00 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000200 RCX: 0000000000080000
RDX: ffffc9000d7ac000 RSI: 00000000000028b0 RDI: 00000000000028b1
RBP: ffffc9000be4fad0 R08: ffffffff911bf5ff R09: 1ffffffff2237ebf
R10: dffffc0000000000 R11: fffffbfff2237ec0 R12: 1ffff920017c9f44
R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff920017c9f65
smp_call_function_single+0x36d/0x5a0 kernel/smp.c:647
task_function_call kernel/events/core.c:120 [inline]
perf_install_in_context+0x5be/0x920 kernel/events/core.c:2948
__do_sys_perf_event_open kernel/events/core.c:12915 [inline]
__se_sys_perf_event_open+0x1836/0x1c50 kernel/events/core.c:12567
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fca4619bf79
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:00007fca46fb2028 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007fca46416090 RCX: 00007fca4619bf79
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000140
RBP: 00007fca462327e0 R08: 0000000000000002 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007fca46416128 R14: 00007fca46416090 R15: 00007ffe13cf4fb8