syzbot

rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (1 GPs behind) idle=bf9c/1/0x4000000000000000 softirq=13161/13162 fqs=4833
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number:  1469853          0            0
rcu: 	cputime:    15400      37099           57   ==> 52520(ms)
rcu: 	(t=10503 jiffies g=11689 q=1571 ncpus=2)
CPU: 0 PID: 5976 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:get_current arch/x86/include/asm/current.h:41 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x60 kernel/kcov.c:215
Code: 00 00 f3 0f 1e fa 53 48 89 fb e8 13 00 00 00 48 8b 3d dc f9 03 0d 48 89 de 5b e9 d3 67 57 00 cc cc cc f3 0f 1e fa 48 8b 04 24 <65> 48 8b 0d b0 93 7c 7e 65 8b 15 b1 93 7c 7e 81 e2 00 01 ff 00 74
RSP: 0018:ffffc90000006d60 EFLAGS: 00000202
RAX: ffffffff8132a2b2 RBX: ffffc90000006e20 RCX: ffff8880211dbc00
RDX: 0000000000000100 RSI: 0000000000000301 RDI: 0000000000000000
RBP: ffffc90000006df0 R08: ffff8880211dbc00 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000000100 R12: ffffffff8132a258
R13: 00000000000000f0 R14: ffffffff8175c250 R15: ffffc90000006d68
FS:  00005555932c7500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000001c255 CR3: 000000002f6e2000 CR4: 00000000003506f0
Call Trace:
 <IRQ>
 arch_stack_walk+0x152/0x190 arch/x86/kernel/stacktrace.c:24
 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+0x6e/0x4b0 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+0x11a/0x2d0 mm/slub.c:3519
 skb_clone+0x1eb/0x370 net/core/skbuff.c:1912
 deliver_clone net/bridge/br_forward.c:125 [inline]
 maybe_deliver+0x98/0x150 net/bridge/br_forward.c:191
 br_flood+0x31b/0x670 net/bridge/br_forward.c:237
 br_dev_xmit+0x1294/0x1920 net/bridge/br_device.c:106
 __netdev_start_xmit include/linux/netdevice.h:4943 [inline]
 netdev_start_xmit include/linux/netdevice.h:4957 [inline]
 xmit_one net/core/dev.c:3644 [inline]
 dev_hard_start_xmit+0x246/0x740 net/core/dev.c:3660
 __dev_queue_xmit+0x19a3/0x3660 net/core/dev.c:4454
 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]
 ip6_finish_output2+0xe06/0x1630 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
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:check_kcov_mode kernel/kcov.c:193 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:245 [inline]
RIP: 0010:__sanitizer_cov_trace_switch+0xb9/0x120 kernel/kcov.c:350
Code: 44 8b 1d 72 8e 7c 7e 41 81 e3 00 01 ff 00 74 13 41 81 fb 00 01 00 00 75 d9 41 83 b8 1c 16 00 00 00 74 cf 45 8b 98 f8 15 00 00 <41> 83 fb 03 75 c2 4d 8b 98 00 16 00 00 45 8b b8 fc 15 00 00 49 c1
RSP: 0018:ffffc900034b7808 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffffffff8f0cd238 RCX: 0000000000000003
RDX: ffffffff813b3e15 RSI: ffffffff8cfa07c0 RDI: 0000000000000002
RBP: ffffc900034b79b8 R08: ffff8880211dbc00 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffc900034b7968
R13: dffffc0000000000 R14: 0000000000000002 R15: ffffffff8f0cd23d
 unwind_next_frame+0x655/0x2970 arch/x86/kernel/unwind_orc.c:505
 __unwind_start+0x66a/0x7e0 arch/x86/kernel/unwind_orc.c:760
 unwind_start arch/x86/include/asm/unwind.h:64 [inline]
 arch_stack_walk+0xf8/0x190 arch/x86/kernel/stacktrace.c:24
 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122
 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46
 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492
 task_work_add+0xd9/0x470 kernel/task_work.c:82
 fput+0xdd/0x1a0 fs/file_table.c:440
 filp_close+0x10f/0x150 fs/open.c:1547
 __range_close fs/file.c:698 [inline]
 __close_range+0x368/0x660 fs/file.c:755
 __do_sys_close_range fs/open.c:1599 [inline]
 __se_sys_close_range fs/open.c:1596 [inline]
 __x64_sys_close_range+0x7a/0x90 fs/open.c:1596
 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: 0033:0x7fe4c5f9cdd9
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:00007ffded4a39f8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: ffffffffffffffda RBX: 00007ffded4a3ae0 RCX: 00007fe4c5f9cdd9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 000000000001c255 R08: 0000000000000001 R09: 0000000000000000
R10: 0000001b33f20000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe4c6215fac R14: 00007fe4c6215fa8 R15: 00007fe4c6215fa0
 </TASK>