rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (10500 ticks this GP) idle=522c/1/0x4000000000000000 softirq=17948/17948 fqs=0
rcu: 	(t=10501 jiffies g=9925 q=399 ncpus=2)
rcu: rcu_preempt kthread timer wakeup didn't happen for 10500 jiffies! g9925 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=3226
rcu: rcu_preempt kthread starved for 10501 jiffies! g9925 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:26632 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
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>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6399 Comm: syz.1.97 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:do_raw_spin_unlock+0x71/0x240
Code: 00 e8 c3 6a 86 00 48 89 d8 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 74 01 00 00 83 3b 00 0f 84 ea 00 00 00 4c 8d 73 10 4d 89 f5 <49> c1 ed 03 43 80 7c 25 00 00 74 08 4c 89 f7 e8 1b 68 86 00 65 48
RSP: 0018:ffffc90000007848 EFLAGS: 00000002
RAX: 0000000000000000 RBX: ffff88804b227ac0 RCX: ffffffff819cb79d
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88804b227ac0
RBP: ffffc90000007918 R08: ffff88804b227ac3 R09: 1ffff11009644f58
R10: dffffc0000000000 R11: ffffed1009644f59 R12: dffffc0000000000
R13: ffff88804b227ad0 R14: ffff88804b227ad0 R15: 1ffff92000000f10
FS:  00007f44ab8966c0(0000) GS:ffff8880b8d73000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f474c3f91b8 CR3: 000000010f992000 CR4: 00000000000006f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 _raw_spin_unlock_irqrestore+0x78/0x110
 hrtimer_try_to_cancel+0x3be/0x420
 hrtimer_cancel+0x3b/0x50
 cpu_clock_event_stop+0xd9/0x130
 __perf_event_overflow+0x580/0xe40
 perf_swevent_hrtimer+0x3b8/0x500
 __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:lock_release+0x5c/0x3e0
Code: f8 08 0f 83 9a 02 00 00 89 c0 48 0f a3 05 fc b4 c0 0d 73 16 e8 c5 f4 08 00 84 c0 75 0d f6 05 c5 b0 aa 0d 01 0f 84 ad 02 00 00 <83> 3d 1d e6 c0 0d 00 0f 84 44 02 00 00 65 8b 05 10 f0 ae 10 85 c0
RSP: 0018:ffffc90002e9f950 EFLAGS: 00000202
RAX: 0000000000000001 RBX: 00007f44aaa11e01 RCX: 21c9fe86afc9f500
RDX: ffffffff8fe17900 RSI: ffffffff8b9ec2c0 RDI: ffffffff8b9ec280
RBP: dffffc0000000000 R08: 0000000000000022 R09: ffffffff81725d05
R10: ffffc90002e9fad8 R11: ffffffff81aaefd0 R12: 00007f44ab896038
R13: ffffffff81725d05 R14: ffffffff8dd3a960 R15: ffffffff81725d05
 unwind_next_frame+0x19a9/0x2390
 arch_stack_walk+0x11c/0x150
 stack_trace_save+0x9c/0xe0
 kasan_save_track+0x3e/0x80
 __kasan_slab_alloc+0x6c/0x80
 kmem_cache_alloc_noprof+0x1c1/0x3c0
 getname_flags+0xb8/0x540
 __x64_sys_mkdirat+0x7a/0xa0
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f44aa98ec29
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:00007f44ab896038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f44aabd5fa0 RCX: 00007f44aa98ec29
RDX: 00000000000001ff RSI: 0000200000000000 RDI: ffffffffffffff9c
RBP: 00007f44aaa11e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f44aabd6038 R14: 00007f44aabd5fa0 R15: 00007fff9c380978
 </TASK>
CPU: 1 UID: 0 PID: 6398 Comm: syz.1.97 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 a6 73 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 51 6f 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 35 6f
RSP: 0000:ffffc9000250f720 EFLAGS: 00000293
RAX: ffffffff81b306ab RBX: 1ffff11009648341 RCX: ffff8881090e9d00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000250f8a0 R08: ffffffff8f5cd537 R09: 1ffffffff1eb9aa6
R10: dffffc0000000000 R11: fffffbfff1eb9aa7 R12: ffff88804b241a08
R13: dffffc0000000000 R14: ffff88813663b1c0 R15: 0000000000000000
FS:  000055556373c500(0000) GS:ffff8881a4173000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f44aaba7cc0 CR3: 000000010f992000 CR4: 00000000000006f0
DR0: 0000200000000300 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
 ptep_clear_flush+0x120/0x170
 do_wp_page+0x1bc2/0x5800
 __handle_mm_fault+0x1033/0x5440
 handle_mm_fault+0x40a/0x8e0
 do_user_addr_fault+0xa7c/0x1380
 exc_page_fault+0x76/0xf0
 asm_exc_page_fault+0x26/0x30
RIP: 0033:0x7f44aa94e6a0
Code: 00 00 80 3d d9 9e 25 00 00 0f 85 eb 00 00 00 48 c7 c0 d8 ff ff ff 64 4c 8b 28 4d 85 ed 0f 84 4f 02 00 00 31 c0 ba 01 00 00 00 <f0> 41 0f b1 55 00 0f 85 b4 02 00 00 49 8b 6d 60 48 8d 05 09 96 25
RSP: 002b:00007fff9c3808c0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000110 RCX: 00007f44aa98ece7
RDX: 0000000000000001 RSI: 0000000000000010 RDI: 0000000000000011
RBP: 000000000000000f R08: 00000000ffffffff R09: 0000000000000000
R10: 0000000000021000 R11: 0000000000000206 R12: 00007fff9c380a70
R13: 00007f44aaba7cc0 R14: 0000000000001000 R15: 0000000000000000
 </TASK>
