------------[ cut here ]------------
WARNING: CPU: 1 PID: 9085 at kernel/rcu/tree_stall.h:1050 rcu_check_gp_start_stall+0x2e4/0x470
Modules linked in:
CPU: 1 UID: 0 PID: 9085 Comm: cmp 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:rcu_check_gp_start_stall+0x2e4/0x470
Code: ff ff 48 c7 c7 20 54 b0 99 be 04 00 00 00 e8 33 39 7c 00 4c 89 f7 b8 01 00 00 00 87 05 55 4b 09 18 85 c0 0f 85 17 ff ff ff 90 <0f> 0b 90 48 81 ff 40 f4 13 8e 74 47 48 c7 c0 60 d9 a3 8f 48 c1 e8
RSP: 0018:ffffc900001e0bb8 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000000a02 RCX: ffffffff81a708bd
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8e13f440
RBP: ffffc900001e0e30 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff3360a84 R12: 0000000000002904
R13: 1ffff11026cc75f2 R14: ffffffff8e13f440 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8881a3c13000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb3592ab440 CR3: 000000000df36000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 rcu_core+0x5fa/0x1770
 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:smp_call_function_many_cond+0xd33/0x12d0
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 b6 63 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 61 5f 0b 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 45 5f
RSP: 0018:ffffc9000340f580 EFLAGS: 00000293
RAX: ffffffff81b4621b RBX: 1ffff11009608341 RCX: ffff888107f09cc0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000340f700 R08: ffffffff8fa3a837 R09: 1ffffffff1f47506
R10: dffffc0000000000 R11: fffffbfff1f47507 R12: ffff88804b041a08
R13: dffffc0000000000 R14: ffff88813663b1c0 R15: 0000000000000000
 on_each_cpu_cond_mask+0x3f/0x80
 flush_tlb_mm_range+0x6b1/0x12d0
 tlb_flush_mmu+0x1a7/0x680
 tlb_finish_mmu+0xc3/0x1d0
 free_ldt_pgtables+0x17b/0x320
 exit_mmap+0x17c/0xb50
 __mmput+0x118/0x430
 exit_mm+0x1da/0x2c0
 do_exit+0x648/0x2300
 do_group_exit+0x21c/0x2d0
 __x64_sys_exit_group+0x3f/0x40
 x64_sys_call+0x21f7/0x2200
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb359369a90
Code: Unable to access opcode bytes at 0x7fb359369a66.
RSP: 002b:00007ffd2dd24588 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007fb35945a860 RCX: 00007fb359369a90
RDX: 00000000000000e7 RSI: 000000000000003c RDI: 0000000000000000
RBP: 00007fb35945a860 R08: 00007ffd2dd24400 R09: 00007ffd2dd244e0
R10: 00007ffd2dd24440 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fb35945e658 R15: 0000000000000001
 </TASK>
