rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=f8d4/1/0x4000000000000000 softirq=61929/61929 fqs=0
rcu: 	(detected by 1, t=10506 jiffies, g=52241, q=967 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 13979 Comm: syz.0.2189 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:lock_acquire+0x58/0x360
Code: 8b 05 bc 62 03 11 48 89 44 24 58 0f 1f 44 00 00 65 8b 05 bf 62 03 11 83 f8 08 0f 83 b8 01 00 00 89 c0 48 0f a3 05 a8 21 06 0e <73> 16 e8 61 02 09 00 84 c0 75 0d f6 05 51 08 f0 0d 01 0f 84 d7 01
RSP: 0018:ffffc900000077e0 EFLAGS: 00000093
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88804b027a98
RBP: ffffffff81ada58b R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed1009604f51 R12: 0000000000000000
R13: ffff88804b027a98 R14: 0000000000000000 R15: 0000000000000001
FS:  00007f29483f66c0(0000) GS:ffff8880b8613000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f29483b3fc8 CR3: 0000000112f3a000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 _raw_spin_lock_irqsave+0xa7/0xf0
 hrtimer_try_to_cancel+0x22b/0x420
 hrtimer_cancel+0x3b/0x50
 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:clear_page_rep+0xb/0x20
Code: ff ff cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa b9 00 02 00 00 31 c0 <f3> 48 ab c3 cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc900035ef5f0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000108
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88803c5357c0
RBP: 1ffffffff1b7b28f R08: ffffffff8fa38f37 R09: 0000000000000000
R10: ffffed10078a6000 R11: fffffbfff1f471e7 R12: fffa80003c535000
R13: fffa800000000000 R14: 1ffffffff1b7b28d R15: 0000000000000003
 post_alloc_hook+0x1bd/0x2a0
 get_page_from_freelist+0x21e4/0x22c0
 __alloc_frozen_pages_noprof+0x181/0x370
 alloc_pages_mpol+0x232/0x4a0
 allocate_slab+0x8a/0x370
 ___slab_alloc+0xbeb/0x1420
 __kmalloc_noprof+0x305/0x4f0
 tomoyo_realpath_from_path+0xe3/0x5d0
 tomoyo_path_number_perm+0x1e8/0x5a0
 security_file_ioctl+0xcb/0x2d0
 __se_sys_ioctl+0x47/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f294a18eba9
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:00007f29483f6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f294a3d5fa0 RCX: 00007f294a18eba9
RDX: 0000200000000040 RSI: 00000000000089e2 RDI: 0000000000000007
RBP: 00007f294a211e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f294a3d6038 R14: 00007f294a3d5fa0 R15: 00007ffd47997168
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10505 jiffies! g52241 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=30153
rcu: rcu_preempt kthread starved for 10506 jiffies! g52241 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:26440 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>
