rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (0 ticks this GP) idle=188c/1/0x4000000000000000 softirq=46357/46357 fqs=751
rcu: 	(detected by 0, t=10502 jiffies, g=39429, q=461 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 11077 Comm: syz.6.1436 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:hrtimer_cancel+0x2c/0x50
Code: 1e fa 55 53 48 89 fb e8 a2 15 12 00 48 89 df e8 9a f9 ff ff 89 c5 31 ff 89 c6 e8 cf 19 12 00 85 ed 78 0c e8 86 15 12 00 eb 1a <e8> 7f 15 12 00 f3 90 48 89 df e8 75 f9 ff ff 85 c0 78 ed 89 c5 e8
RSP: 0018:ffffc900001e0990 EFLAGS: 00000086
RAX: 00000000ffffffff RBX: ffff88803a29d2a8 RCX: 0000000000010000
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 00000000ffffffff
RBP: 00000000ffffffff R08: ffff888136627a83 R09: 1ffff11026cc4f50
R10: dffffc0000000000 R11: ffffed1026cc4f51 R12: ffff88803a29d350
R13: dffffc0000000000 R14: ffff88803a29d2a8 R15: fffffffffffedcbf
FS:  00007f27ca4be6c0(0000) GS:ffff8881a3c12000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f27ca49cfc8 CR3: 0000000029fe8000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 cpu_clock_event_stop+0xd9/0x130
 __perf_event_overflow+0x580/0xe40
 perf_swevent_hrtimer+0x3c5/0x550
 __hrtimer_run_queues+0x4e0/0xc60
 hrtimer_interrupt+0x45b/0xaa0
 __sysvec_apic_timer_interrupt+0x10b/0x410
 sysvec_apic_timer_interrupt+0xa1/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:_raw_spin_unlock_irqrestore+0xa8/0x110
Code: 74 05 e8 2b fc 49 f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> e3 a0 12 f6 65 8b 05 6c 71 23 07 85 c0 74 40 48 c7 04 24 0e 36
RSP: 0018:ffffc9000679faa0 EFLAGS: 00000206
RAX: 4eb07e605d2ec500 RBX: 0000000000000a02 RCX: 4eb07e605d2ec500
RDX: 0000000000000000 RSI: ffffffff8d9baa63 RDI: 0000000000000001
RBP: ffffc9000679fb28 R08: ffffffff8fa3b237 R09: 1ffffffff1f47646
R10: dffffc0000000000 R11: fffffbfff1f47647 R12: dffffc0000000000
R13: 1ffff11026cc75be R14: ffff888021a20a10 R15: 1ffff92000cf3f54
 try_to_wake_up+0x7b7/0x12b0
 wake_up_q+0x85/0xd0
 futex_wake+0x4a0/0x560
 do_futex+0x395/0x420
 __se_sys_futex+0x36f/0x400
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f27c958eba9
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:00007f27ca4be0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f27c97d5fa8 RCX: 00007f27c958eba9
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f27c97d5fac
RBP: 00007f27c97d5fa0 R08: 7fffffffffffffff R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f27c97d6038 R14: 00007ffdda469ed0 R15: 00007ffdda469fb8
 </TASK>
rcu: rcu_preempt kthread starved for 9000 jiffies! g39429 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:26120 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_timeout+0x12b/0x270
 rcu_gp_fqs_loop+0x301/0x1540
 rcu_gp_kthread+0x99/0x390
 kthread+0x711/0x8a0
 ret_from_fork+0x439/0x7d0
 ret_from_fork_asm+0x1a/0x30
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 5772 Comm: syz-executor 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: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:ffffc900029ef560 EFLAGS: 00000293
RAX: ffffffff81b4621b RBX: 1ffff11026cc7f61 RCX: ffff88801f493980
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900029ef6e0 R08: ffffffff8fa3b237 R09: 1ffffffff1f47646
R10: dffffc0000000000 R11: fffffbfff1f47647 R12: ffff88813663fb08
R13: dffffc0000000000 R14: ffff88804b03b1c0 R15: 0000000000000001
FS:  000055556c15b500(0000) GS:ffff8880b8612000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fccf0b2e060 CR3: 0000000100ec6000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80
 flush_tlb_mm_range+0x6b1/0x12d0
 tlb_flush_mmu+0x1a7/0x680
 tlb_finish_mmu+0xc3/0x1d0
 vms_clear_ptes+0x42c/0x540
 vms_complete_munmap_vmas+0x206/0x8a0
 do_vmi_align_munmap+0x358/0x420
 do_vmi_munmap+0x253/0x2e0
 __vm_munmap+0x23b/0x3d0
 __x64_sys_munmap+0x60/0x70
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd8b178ec37
Code: 00 00 00 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 0b 00 00 00 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:00007ffd295653a8 EFLAGS: 00000246 ORIG_RAX: 000000000000000b
RAX: ffffffffffffffda RBX: 00007fd8b26cd000 RCX: 00007fd8b178ec37
RDX: 00007fd8b178cdb0 RSI: 0000000000009000 RDI: 00007fd8b26cd000
RBP: 0000000000009000 R08: 00007ffd29565440 R09: 0000000000000000
R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000002b49
R13: 000055556c1729cc R14: 00007ffd29565440 R15: 0000000000000000
 </TASK>
