rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (10499 ticks this GP) idle=5684/1/0x4000000000000000 softirq=16216/16219 fqs=4568
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number:  1031993          0            0
rcu: 	cputime:    25351      27138           90   ==> 52490(ms)
rcu: 	(t=10500 jiffies g=8233 q=3296 ncpus=2)
CPU: 0 UID: 0 PID: 6443 Comm: syz.0.179 Not tainted 6.16.0-rc6-syzkaller-00411-g95993dc3039e-dirty #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:rcu_read_unlock_special+0x87/0x4c0
Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 62 2c f8 10 41 f7 c6 00 00 f0 00 74 49 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b
RSP: 0018:ffffc900000075a0 EFLAGS: 00000206
RAX: 8108ec0d6fa3db00 RBX: 1ffff92000000ebc RCX: 8108ec0d6fa3db00
RDX: 0000000000000002 RSI: ffffffff8d99883e RDI: ffffffff8be29f40
RBP: ffffc90000007698 R08: ffffffff8fa1e8f7 R09: 1ffffffff1f43d1e
R10: dffffc0000000000 R11: fffffbfff1f43d1f R12: ffffffff8e144400
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
FS:  00007fa91197c6c0(0000) GS:ffff8880b861f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2fd1fffc CR3: 00000000293a0000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 __rcu_read_unlock+0x84/0xe0
 unwind_next_frame+0x19ae/0x2390
 arch_stack_walk+0x11c/0x150
 stack_trace_save+0x9c/0xe0
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x62/0x70
 kfree+0x18e/0x440
 slab_free_after_rcu_debug+0x60/0x2a0
 rcu_core+0xca8/0x1710
 handle_softirqs+0x286/0x870
 __irq_exit_rcu+0xca/0x1f0
 irq_exit_rcu+0x9/0x30
 sysvec_apic_timer_interrupt+0xa6/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:_raw_spin_unlock_irqrestore+0xa8/0x110
Code: 74 05 e8 cb 8e 56 f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 13 bd 1f f6 65 8b 05 bc e9 2e 07 85 c0 74 40 48 c7 04 24 0e 36
RSP: 0018:ffffc9000357f080 EFLAGS: 00000206
RAX: 8108ec0d6fa3db00 RBX: 0000000000000a02 RCX: 8108ec0d6fa3db00
RDX: 0000000000000006 RSI: ffffffff8d99883e RDI: 0000000000000001
RBP: ffffc9000357f108 R08: ffffffff8fa1e8f7 R09: 1ffffffff1f43d1e
R10: dffffc0000000000 R11: fffffbfff1f43d1f R12: dffffc0000000000
R13: ffff888022c9b658 R14: ffffffff99d7c520 R15: 1ffff920006afe10
 debug_object_activate+0x2e2/0x420
 kvfree_call_rcu+0x4f/0x410
 ipv6_mc_destroy_dev+0x3c5/0x5a0
 addrconf_ifdown+0x139e/0x1880
 addrconf_notify+0x1bc/0x1010
 notifier_call_chain+0x1b6/0x3e0
 unregister_netdevice_many_notify+0x15d8/0x2320
 default_device_exit_batch+0x819/0x890
 ops_undo_list+0x525/0x990
 setup_net+0x3e2/0x4b0
 copy_net_ns+0x31b/0x4d0
 create_new_namespaces+0x3f3/0x720
 copy_namespaces+0x438/0x4b0
 copy_process+0x1700/0x3b80
 kernel_clone+0x21e/0x870
 __x64_sys_clone+0x18b/0x1e0
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa910b8e9a9
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fa91197bfe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007fa910db5fa0 RCX: 00007fa910b8e9a9
RDX: 0000200000000040 RSI: 0000200000000750 RDI: 0000000040000000
RBP: 00007fa910c10d69 R08: 0000200000000780 R09: 0000200000000780
R10: 00002000000003c0 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fa910db5fa0 R15: 00007ffc6938a258
 </TASK>
sched: DL replenish lagged too much
