rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (10500 ticks this GP) idle=948c/1/0x4000000000000000 softirq=22070/22073 fqs=5231
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number:  1275953          4            0
rcu: 	cputime:    10095      42394           33   ==> 52490(ms)
rcu: 	(t=10500 jiffies g=17609 q=5460 ncpus=2)
CPU: 0 UID: 0 PID: 7812 Comm: syz.2.535 Not tainted syzkaller #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:br_nf_post_routing+0x4/0xfe0
Code: ab f7 e9 c4 f7 ff ff 66 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa <55> 41 57 41 56 41 55 41 54 53 48 83 ec 48 49 89 d6 48 89 f3 49 bc
RSP: 0018:ffffc90000006d28 EFLAGS: 00000246
RAX: 1ffff1102145d134 RBX: ffffffff8a8602b0 RCX: ffff888173b03b00
RDX: ffffc90000006de0 RSI: ffff888114f96300 RDI: 0000000000000000
RBP: dffffc0000000000 R08: ffff888173b03b00 R09: 0000000000000004
R10: 0000000000000003 R11: ffffffff8a8602b0 R12: 0000000000000001
R13: ffff88810a2e8998 R14: 1ffff1102145d130 R15: ffff88810a2e89a0
FS:  00007f215bdfa6c0(0000) GS:ffff88818dc88000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0a3cf45000 CR3: 0000000173e16000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 nf_hook_slow+0xc5/0x220
 NF_HOOK+0x23e/0x3f0
 br_forward_finish+0xd3/0x130
 br_nf_forward_finish+0xa5e/0xe90
 NF_HOOK+0x64e/0x6e0
 br_nf_forward_ip+0x7ef/0xa30
 nf_hook_slow+0xc5/0x220
 NF_HOOK+0x23e/0x3f0
 __br_forward+0x397/0x540
 br_handle_frame_finish+0x1521/0x1c80
 br_nf_hook_thresh+0x3dd/0x4c0
 br_nf_pre_routing_finish_ipv6+0x91f/0xc30
 br_nf_pre_routing_ipv6+0x374/0x6f0
 br_handle_frame+0x1277/0x1510
 __netif_receive_skb_core+0x98f/0x3170
 process_backlog+0x76d/0x1950
 __napi_poll+0xae/0x340
 net_rx_action+0x627/0xf70
 handle_softirqs+0x22a/0x840
 __irq_exit_rcu+0xca/0x220
 irq_exit_rcu+0x9/0x30
 sysvec_apic_timer_interrupt+0xa6/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:rcu_read_unlock_special+0x1d/0x480
Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 41 55 41 54 53 48 83 ec 10 65 8b 2d eb e4 8d 11 f7 c5 00 00 f0 00 74 14 <48> 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d e9 40 ad 00 0a cc 49 89
RSP: 0018:ffffc90006156fe0 EFLAGS: 00000206
RAX: 0000000000000006 RBX: 0000000000000246 RCX: 0000000000000001
RDX: 0000000000000007 RSI: ffffffff8dfab075 RDI: ffffffff8c28b6e0
RBP: ffff88818dc88000 R08: ffffffff9030bef7 R09: 1ffffffff20617de
R10: dffffc0000000000 R11: fffffbfff20617df R12: ffffffff8e962978
R13: dffffc0000000000 R14: ffff88812103bed8 R15: 1ffff110242077db
 __rcu_read_unlock+0x83/0xe0
 unwind_next_frame+0x1bbf/0x2550
 arch_stack_walk+0x11b/0x150
 stack_trace_save+0xa9/0x100
 save_stack+0x122/0x230
 __reset_page_owner+0x71/0x1f0
 __free_frozen_pages+0xbc7/0xd30
 __mmdrop+0xb5/0x750
 finish_task_switch+0x624/0xbe0
 __schedule+0x1829/0x5740
 preempt_schedule_irq+0x4d/0xa0
 irqentry_exit+0x14f/0x760
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:__sanitizer_cov_trace_cmp1+0x8/0x90
Code: cc cc cc cc 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 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 15 d8 b2 73 11 65 8b 0d f9 b2 73 11 81 e1 00 01 ff 00 74
RSP: 0018:ffffc90006157840 EFLAGS: 00000246
RAX: ffffffff8ba1ba3c RBX: 0000000000000000 RCX: ffff888173b03b00
RDX: 0000000000000000 RSI: 000000000000000e RDI: 0000000000000000
RBP: 000000000000000e R08: ffff888173b03b00 R09: 0000000000000004
R10: 0000000000000004 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff888173a1f600 R14: 0000000000000001 R15: ffffffffffffffff
 mas_next_slot+0x2ec/0xd10
 mas_find+0xb0e/0xd30
 acct_collect+0x20d/0x7c0
 do_exit+0x615/0x22c0
 do_group_exit+0x21b/0x2d0
 get_signal+0x1284/0x1330
 arch_do_signal_or_restart+0xbc/0x840
 exit_to_user_mode_loop+0x8c/0x4d0
 do_syscall_64+0x33e/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f215af9cdd9
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:00007f215bdfa028 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: 0000000000000005 RBX: 00007f215b216090 RCX: 00007f215af9cdd9
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 00002000000000c0
RBP: 00007f215b032d69 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007f215b216128 R14: 00007f215b216090 R15: 00007ffdc2f98528
 </TASK>
sched: DL replenish lagged too much
