rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (3 ticks this GP) idle=2adc/1/0x4000000000000000 softirq=43744/43744 fqs=2
rcu: 	(detected by 1, t=10502 jiffies, g=49581, q=359 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5061 Comm: udevd Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:__kasan_check_read+0x0/0x20
Code: 21 8e 48 89 de e8 d0 ab f6 fe 31 ed eb cf cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 89 f6 48 8b 0c 24 31 d2 e9 8f e5 ff ff 66 66 66 66 66
RSP: 0018:ffffc900000062a0 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffffff9a681e40 RCX: 0000000000010104
RDX: 0000000000000005 RSI: 0000000000000004 RDI: ffffffff9a681e40
RBP: ffff8881bca61558 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000000c4c R12: dffffc0000000000
R13: ffff8881bca61540 R14: ffffffff9a681e44 R15: 1ffff1103794c2aa
FS:  00007f1a360c7c80(0000) GS:ffff88818dc90000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555577f609e8 CR3: 0000000114040000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 do_raw_spin_unlock+0x4d/0x210
 _raw_spin_unlock_irqrestore+0x23/0x80
 debug_object_activate+0x320/0x580
 enqueue_hrtimer+0xa9/0x2c0
 __hrtimer_run_queues+0x4d2/0xa20
 hrtimer_interrupt+0x44b/0x950
 __sysvec_apic_timer_interrupt+0x102/0x430
 sysvec_apic_timer_interrupt+0x52/0xc0
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:stack_trace_consume_entry+0x51/0x280
Code: 0f b6 44 15 00 84 c0 0f 85 09 01 00 00 44 8b 4f 10 4c 8d 77 08 4d 89 f5 49 c1 ed 03 41 0f b6 44 15 00 84 c0 0f 85 22 01 00 00 <45> 3b 0e 73 3a 48 8d 5f 0c 49 89 df 49 c1 ef 03 41 0f b6 04 17 84
RSP: 0018:ffffc90000006678 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffc90000006780 RCX: 0000000000000100
RDX: dffffc0000000000 RSI: ffffffff8187d07a RDI: ffffc90000006780
RBP: 1ffff92000000cf2 R08: ffffc90000006790 R09: 0000000000000017
R10: ffffc90000006718 R11: ffffffff81b0d910 R12: ffff8881140c3b00
R13: 1ffff92000000cf1 R14: ffffc90000006788 R15: ffffc900000066c8
 arch_stack_walk+0x10f/0x150
 stack_trace_save+0xa9/0x100
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x5c/0x80
 kfree+0x1c5/0x640
 skb_release_data+0x828/0xa60
 __kfree_skb+0x5d/0x210
 tcp_ack+0x284f/0x7e00
 tcp_rcv_established+0x1484/0x2800
 tcp_v4_do_rcv+0x964/0x13c0
 tcp_v4_rcv+0x2681/0x2ff0
 ip_protocol_deliver_rcu+0x221/0x440
 ip_local_deliver_finish+0x3bb/0x6f0
 NF_HOOK+0x336/0x3c0
 ip_sublist_rcv_finish+0x1f0/0x240
 ip_sublist_rcv+0x761/0xa70
 ip_list_rcv+0x3f1/0x450
 __netif_receive_skb_list_core+0x7e5/0x810
 netif_receive_skb_list_internal+0x995/0xcf0
 gro_receive_skb+0x632/0xce0
 e1000_clean_rx_irq+0x980/0x11a0
 e1000_clean+0xe8f/0x2a90
 __napi_poll+0xae/0x340
 net_rx_action+0x627/0xf70
 handle_softirqs+0x22a/0x840
 __irq_exit_rcu+0xca/0x220
 irq_exit_rcu+0x9/0x30
 common_interrupt+0xbb/0xe0
 </IRQ>
 <TASK>
 asm_common_interrupt+0x26/0x40
RIP: 0010:__up_read+0x1f3/0x6b0
Code: 24 60 41 83 e4 03 4c 89 ff be 08 00 00 00 e8 a4 cf 8f 00 4c 89 f7 be 08 00 00 00 e8 97 cf 8f 00 48 8b 44 24 60 f0 4d 0f b1 27 <74> 11 49 89 c4 48 89 44 24 60 48 83 e0 fc 48 39 d8 74 c5 48 89 5c
RSP: 0018:ffffc900074ffca0 EFLAGS: 00000246
RAX: ffff8881140c3b01 RBX: ffff8881140c3b00 RCX: ffffffff81a13229
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffc900074ffd00
RBP: ffffc900074ffd78 R08: ffffc900074ffd07 R09: 1ffff92000e9ffa0
R10: dffffc0000000000 R11: fffff52000e9ffa1 R12: 0000000000000001
R13: 1ffff92000e9ff9c R14: ffffc900074ffd00 R15: ffff8881ae916ba0
 iterate_dir+0x453/0x570
 __se_sys_getdents64+0xf1/0x280
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1a35cf9910
Code: 87 43 04 ff c8 7e 08 48 89 ef e8 4d 0e fc ff 4c 89 e0 5b 5d 41 5c c3 b8 ff ff ff 7f 48 39 c2 48 0f 47 d0 b8 d9 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 10 48 8b 15 e9 74 0f 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffe0b227718 EFLAGS: 00000293 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 000056531c5f8110 RCX: 00007f1a35cf9910
RDX: 0000000000008000 RSI: 000056531c5f8140 RDI: 000000000000000d
RBP: 000056531c5f8114 R08: 000056531c5f8110 R09: 0000000001000000
R10: 0000000000000812 R11: 0000000000000293 R12: 000056531c5e9f10
R13: fffffffffffffe60 R14: 0000000000000002 R15: 000056531c5f8140
 </TASK>
rcu: rcu_preempt kthread starved for 10498 jiffies! g49581 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:26880 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 __schedule+0x17b4/0x5680
 schedule+0x164/0x360
 schedule_timeout+0x158/0x2c0
 rcu_gp_fqs_loop+0x312/0x11d0
 rcu_gp_kthread+0x9e/0x2b0
 kthread+0x388/0x470
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 10284 Comm: syz.2.1039 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:smp_call_function_many_cond+0xfd4/0x13d0
Code: 89 ee 83 e6 01 31 ff e8 fa fc 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 a5 f8 0b 00 eb 37 f3 90 43 0f b6 04 2c <84> c0 75 10 41 f7 06 01 00 00 00 74 1e e8 8a f8 0b 00 eb e5 44 89
RSP: 0018:ffffc9000b03fae0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff88823c63c2c8 RCX: 0000000000080000
RDX: ffffc90008be4000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc9000b03fc10 R08: ffffffff9030b1f7 R09: 1ffffffff206163e
R10: dffffc0000000000 R11: ffffffff81745300 R12: 1ffff110242085b9
R13: dffffc0000000000 R14: ffff888121042dc8 R15: 0000000000000000
FS:  00007fc08941d6c0(0000) GS:ffff8882a9290000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c4126bb CR3: 00000001ae7b6000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 clock_was_set+0x70a/0x7d0
 do_settimeofday64+0x340/0x570
 __x64_sys_clock_settime+0x253/0x2a0
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc08859cdd9
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:00007fc08941d028 EFLAGS: 00000246 ORIG_RAX: 00000000000000e3
RAX: ffffffffffffffda RBX: 00007fc088815fa0 RCX: 00007fc08859cdd9
RDX: 0000000000000000 RSI: 0000200000000240 RDI: 0000000000000000
RBP: 00007fc088632d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc088816038 R14: 00007fc088815fa0 R15: 00007ffe54639e38
 </TASK>
