rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (10499 ticks this GP) idle=2c0c/1/0x4000000000000000 softirq=16329/16329 fqs=7
rcu: 	(t=10500 jiffies g=8313 q=582 ncpus=2)
rcu: rcu_preempt kthread starved for 10485 jiffies! g8313 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R  running task     stack:27320 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 __schedule+0x16f5/0x4d00
 schedule+0x165/0x360
 schedule_timeout+0x12b/0x270
 rcu_gp_fqs_loop+0x301/0x1540
 rcu_gp_kthread+0x99/0x390
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6353 Comm: syz.0.195 Not tainted 6.16.0-rc6-syzkaller-00411-g95993dc3039e #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:native_queued_spin_lock_slowpath+0xaf/0x8e0
Code: 00 00 00 c7 44 24 60 00 00 00 00 0f 1f 44 00 00 4c 8d 74 24 60 49 89 df 49 c1 ef 03 41 bd 01 00 00 00 eb 06 89 44 24 60 f3 90 <48> 89 df be 04 00 00 00 e8 94 28 b2 f6 48 b8 00 00 00 00 00 fc ff
RSP: 0018:ffffc900068e7600 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffffff8e2cb4c0 RCX: ffffffff8b71260c
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff8e2cb4c0
RBP: ffffc900068e76f8 R08: ffffffff8e2cb4c3 R09: 1ffffffff1c59698
R10: dffffc0000000000 R11: fffffbfff1c59699 R12: 1ffff92000d1cec8
R13: 0000000000000001 R14: ffffc900068e7660 R15: 1ffffffff1c59698
FS:  00007fe9d63996c0(0000) GS:ffff8880b861f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9d20f18360 CR3: 000000001f100000 CR4: 00000000000006f0
DR0: 0100000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 queued_spin_lock_slowpath+0x43/0x50
 do_raw_spin_lock+0x21f/0x290
 __register_sysctl_table+0x9ed/0x1340
 setup_mq_sysctls+0x430/0x4b0
 copy_ipcs+0x314/0x4f0
 create_new_namespaces+0x218/0x720
 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: 0033:0x7fe9d558e9a9
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:00007fe9d6398fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007fe9d57b6160 RCX: 00007fe9d558e9a9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000028280000
RBP: 00007fe9d5610d69 R08: ffffffffff600000 R09: ffffffffff600000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fe9d57b6160 R15: 00007fff24c76028
 </TASK>
CPU: 1 UID: 0 PID: 6345 Comm: syz.1.193 Not tainted 6.16.0-rc6-syzkaller-00411-g95993dc3039e #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:ffffc900001e04c0 EFLAGS: 00000206
RAX: e929532427dc9a00 RBX: 1ffff9200003c0a0 RCX: e929532427dc9a00
RDX: 0000000000000002 RSI: ffffffff8d998836 RDI: ffffffff8be29f40
RBP: ffffc900001e05b8 R08: ffffffff8fa1e8f7 R09: 1ffffffff1f43d1e
R10: dffffc0000000000 R11: fffffbfff1f43d1f R12: ffffffff8e144400
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000002
FS:  00007f0f73de06c0(0000) GS:ffff8881a3c1f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000010d528000 CR4: 00000000000006f0
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_slab_alloc+0x6c/0x80
 kmem_cache_alloc_node_noprof+0x1bb/0x3c0
 kmalloc_reserve+0xbd/0x290
 __alloc_skb+0x142/0x2d0
 wg_packet_send_keepalive+0x65/0x2c0
 call_timer_fn+0x17e/0x5f0
 __run_timer_base+0x61a/0x860
 run_timer_softirq+0xb7/0x180
 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:__sanitizer_cov_trace_pc+0x18/0x70
Code: cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 08 10 a0 92 65 8b 15 28 e7 df 10 <81> e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 3c 16 00 00
RSP: 0018:ffffc90006a0f480 EFLAGS: 00000296
RAX: ffffffff825be37e RBX: dffffc0000000000 RCX: ffff88801f833980
RDX: 0000000080000001 RSI: ffff888101af9800 RDI: ffffc90006a0f4d8
RBP: ffffc90006a0f710 R08: 0000000000000004 R09: 0000000001af9802
R10: dffffc0000000000 R11: fffffbfff1f43d1f R12: dffffc0000000000
R13: dffffc0000000000 R14: ffff8881084644b8 R15: ffff888101af9800
 find_entry+0x2e/0x250
 xlate_dir+0xcc/0x170
 xlate_dir+0x57/0x170
 put_links+0x9f/0x360
 drop_sysctl_table+0xef/0x510
 drop_sysctl_table+0x39c/0x510
 unregister_sysctl_table+0x41/0x60
 neigh_sysctl_unregister+0x78/0xa0
 inetdev_event+0x7ae/0x15b0
 notifier_call_chain+0x1b6/0x3e0
 unregister_netdevice_many_notify+0x15d8/0x2320
 unregister_netdevice_queue+0x33c/0x380
 __tun_detach+0xda4/0x1560
 tun_chr_close+0x10a/0x1c0
 __fput+0x44c/0xa70
 fput_close_sync+0x119/0x200
 __x64_sys_close+0x7f/0x110
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0f72f8e9a9
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:00007f0f73de0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 00007f0f731b5fa0 RCX: 00007f0f72f8e9a9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007f0f73010d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f0f731b5fa0 R15: 00007ffc3acd7dd8
 </TASK>
sched: DL replenish lagged too much
