rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=7af4/1/0x4000000000000000 softirq=51780/51782 fqs=1
rcu: 	(detected by 0, t=10506 jiffies, g=48673, q=440 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5653 Comm: kworker/1:3 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
Workqueue: events_freezable_pwr_efficient sync_hw_clock
RIP: 0010:lock_release+0x277/0x3c0
Code: e8 6e 31 00 00 48 8b 5c 24 08 48 c7 c7 1d d2 6f 8e e8 0d 47 41 0a b8 ff ff ff ff 65 0f c1 05 f8 98 f1 11 83 f8 01 75 2e 9c 58 <a9> 00 02 00 00 75 42 f7 c3 00 02 00 00 75 47 65 48 8b 05 4a 54 f1
RSP: 0018:ffffc90000a38c80 EFLAGS: 00000046
RAX: 0000000000000046 RBX: 0000000000000002 RCX: 8000000001000002
RDX: 8000000001000001 RSI: ffffffff8e6fd21d RDI: ffffffff8c6d9c80
RBP: ffff88816abaaa00 R08: ffff888168bd4483 R09: 1ffff1102d17a890
R10: dffffc0000000000 R11: ffffed102d17a891 R12: 0000000000000002
R13: 0000000000000002 R14: ffff8881b779a2c0 R15: ffff88816aba9e00
FS:  0000000000000000(0000) GS:ffff8882a8cd6000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f411b9f9ff8 CR3: 00000001ad7d0000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 _raw_spin_unlock+0x16/0x50
 advance_sched+0x99a/0xc80
 __hrtimer_run_queues+0x3bc/0xa10
 hrtimer_interrupt+0x4cd/0xaa0
 __sysvec_apic_timer_interrupt+0x102/0x430
 sysvec_apic_timer_interrupt+0xa1/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:_raw_spin_unlock_irqrestore+0x47/0x80
Code: f7 e8 ed 8c bc f5 f7 c3 00 02 00 00 74 05 e8 f0 c9 e8 f5 9c 58 a9 00 02 00 00 75 29 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 84 a6 ad f5 65 48 8b 05 bc 6b ad 07 48 85 c0 74 18 5b 41 5e e9
RSP: 0018:ffffc9000609f8b8 EFLAGS: 00000206
RAX: 0000000000000002 RBX: 0000000000000286 RCX: 8000000000000001
RDX: 0000000000000006 RSI: ffffffff8e474924 RDI: 0000000000000001
RBP: ffffffff9ac523e0 R08: ffffffff907a197f R09: 1ffffffff20f432f
R10: dffffc0000000000 R11: fffffbfff20f4330 R12: ffff888100077590
R13: ffff888100077578 R14: ffffffff9ac523e8 R15: dffffc0000000000
 debug_object_assert_init+0x20d/0x380
 hrtimer_start_range_ns+0x3d/0x3e0
 sync_hw_clock+0x3ae/0x4c0
 process_scheduled_works+0xc3d/0x1630
 worker_thread+0xa47/0xfb0
 kthread+0x38b/0x480
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>
rcu: rcu_preempt kthread starved for 10500 jiffies! g48673 f0x0 RCU_GP_WAIT_FQS(5) ->state=R ->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:27600 pid:17    tgid:17    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 __schedule+0x17db/0x58f0
 schedule+0x164/0x2b0
 schedule_timeout+0x152/0x2c0
 rcu_gp_fqs_loop+0x30c/0x11f0
 rcu_gp_kthread+0x9e/0x2b0
 kthread+0x38b/0x480
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 12867 Comm: syz.1.2909 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+0x61e/0x1500
Code: b6 04 04 84 c0 0f 85 d5 03 00 00 44 8b 3b 44 89 fe 83 e6 01 31 ff e8 51 54 0c 00 41 83 e7 01 75 07 e8 46 4f 0c 00 eb 3f f3 90 <48> b8 00 00 00 00 00 fc ff df 41 0f b6 04 04 84 c0 75 0f f7 03 01
RSP: 0018:ffffc90009db7320 EFLAGS: 00000293
RAX: ffffffff81bb697e RBX: ffff88823c641708 RCX: ffff888113cabc00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90009db7470 R08: ffff888113cad19f R09: 1ffff11022795a33
R10: dffffc0000000000 R11: 0000000000000000 R12: 1ffff110478c82e1
R13: 0000000000000001 R14: ffff88823c641700 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff88818d6d6000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f411ae1a818 CR3: 00000001ad7d0000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 flush_tlb_mm_range+0x8ff/0x1090
 tlb_flush_mmu+0x1af/0xa30
 tlb_finish_mmu+0xf4/0x220
 free_ldt_pgtables+0x192/0x360
 exit_mmap+0x1bf/0x9f0
 __mmput+0x118/0x420
 exit_mm+0x221/0x2d0
 do_exit+0x6cd/0x2360
 do_group_exit+0x22d/0x2f0
 get_signal+0x121b/0x12c0
 arch_do_signal_or_restart+0xbb/0x860
 exit_to_user_mode_loop+0x10e/0x770
 do_syscall_64+0x328/0x520
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f411ab9e159
Code: Unable to access opcode bytes at 0x7f411ab9e12f.
RSP: 002b:00007f411b9fa0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f411ae25fa8 RCX: 00007f411ab9e159
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f411ae25fa8
RBP: 00007f411ae25fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f411ae26038 R14: 00007fff4b885c30 R15: 00007fff4b885d18
 </TASK>
