rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=656c/1/0x4000000000000000 softirq=87909/87910 fqs=102
rcu: 	(detected by 0, t=10502 jiffies, g=78257, q=516 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 17611 Comm: syz.2.2829 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:_raw_spin_unlock_irqrestore+0xad/0x110
Code: 4b 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 43 ef 13 f6 <65> 8b 05 0c 42 24 07 85 c0 74 40 48 c7 04 24 0e 36 e0 45 4b c7 04
RSP: 0018:ffffc900001e0be0 EFLAGS: 00000013
RAX: 0000000000010002 RBX: 0000000000000802 RCX: 0000000000010000
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 00000000ffffffff
RBP: ffffc900001e0c78 R08: ffffffff99d8c1eb R09: 1ffffffff33b183d
R10: dffffc0000000000 R11: fffffbfff33b183e R12: dffffc0000000000
R13: ffff88810d100f88 R14: ffffffff99d8c1e8 R15: 1ffff9200003c17c
FS:  00007f2e74e376c0(0000) GS:ffff8881a3c1b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2e74df4fc8 CR3: 000000010eb5c000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 debug_object_activate+0x2e2/0x420
 enqueue_hrtimer+0x30/0x3a0
 __hrtimer_run_queues+0x656/0xc60
 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:its_return_thunk+0x0/0x10
Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc <c3> cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 e9 6b 13 b7 f5 cc
RSP: 0018:ffffc9000377f678 EFLAGS: 00000293
RAX: ffffffff822e3ad7 RBX: 0000000000000000 RCX: ffff888023088000
RDX: 0000000000000000 RSI: 0000000000000200 RDI: 0000000000000018
RBP: 0000000000000200 R08: ffff88801d8b477f R09: 1ffff11003b168ef
R10: dffffc0000000000 R11: ffffed1003b168f0 R12: ffff88801d8b4780
R13: 0000000000000018 R14: 0000000000062401 R15: 0000000000062418
 __page_table_check_zero+0x1f7/0x530
 post_alloc_hook+0x253/0x2a0
 get_page_from_freelist+0x21e4/0x22c0
 __alloc_frozen_pages_noprof+0x181/0x370
 alloc_pages_mpol+0x232/0x4a0
 alloc_pages_noprof+0xa9/0x190
 io_region_allocate_pages+0xe9/0x4c0
 io_create_region+0x374/0x480
 io_allocate_scq_urings+0x235/0x7f0
 io_uring_create+0x52b/0xb60
 __se_sys_io_uring_setup+0x264/0x270
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2e73f8ebe9
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:00007f2e74e36fc8 EFLAGS: 00000202 ORIG_RAX: 00000000000001a9
RAX: ffffffffffffffda RBX: 00007f2e741b5fa0 RCX: 00007f2e73f8ebe9
RDX: 0000000000000000 RSI: 0000200000000040 RDI: 0000000000000002
RBP: 0000200000000040 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000002 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread starved for 10298 jiffies! g78257 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:27496 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+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 15318 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+0xd38/0x12d0
Code: 89 ee 83 e6 01 31 ff e8 b6 62 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 61 5e 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 5e 0b 00 eb e4 44
RSP: 0000:ffffc9000380f720 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 1ffff11026cc7f61 RCX: ffff88802913d640
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000380f8a0 R08: ffffffff8fa38337 R09: 1ffffffff1f47066
R10: dffffc0000000000 R11: fffffbfff1f47067 R12: ffff88813663fb08
R13: dffffc0000000000 R14: ffff88804b03b1c0 R15: 0000000000000001
FS:  000055558e699500(0000) GS:ffff8880b861b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558e6b45c8 CR3: 000000012de70000 CR4: 00000000000006f0
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+0xa81/0x1390
 exc_page_fault+0x76/0xf0
 asm_exc_page_fault+0x26/0x30
RIP: 0033:0x7faea8b4d06f
Code: 8d 34 19 48 39 d5 48 89 75 60 0f 95 c2 48 29 d8 48 83 c1 10 0f b6 d2 48 83 c8 01 48 c1 e2 02 48 09 da 48 83 ca 01 48 89 51 f8 <48> 89 46 08 eb 80 48 8d 0d f1 e8 0e 00 48 8d 15 f5 fa 0e 00 bf 01
RSP: 002b:00007ffe7f59cec0 EFLAGS: 00010206
RAX: 0000000000018a41 RBX: 0000000000008040 RCX: 000055558e6ac590
RDX: 0000000000008041 RSI: 000055558e6b45c0 RDI: 0000000000000004
RBP: 00007faea8d87cc0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000001000 R11: 0000000000000802 R12: 0000000000008030
R13: 0000000000000076 R14: 00007faea8d87d20 R15: 0000000000000000
 </TASK>
