syzbot

syz-executor.0 (11135) used greatest stack depth: 22896 bytes left
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (10500 ticks this GP) idle=836/1/0x4000000000000002 softirq=14550/14550 fqs=0 
rcu: 	 (t=10501 jiffies g=12681 q=2783)
rcu: rcu_preempt kthread starved for 10502 jiffies! g12681 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
rcu: RCU grace-period kthread stack dump:
rcu_preempt     I29208    10      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 schedule_timeout+0x4cf/0xfe0 kernel/time/timer.c:1818
 rcu_gp_kthread+0xdad/0x21c0 kernel/rcu/tree.c:2202
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
NMI backtrace for cpu 1
CPU: 1 PID: 11132 Comm: syz-executor.4 Not tainted 4.19.171-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x15f/0x19c kernel/rcu/tree.c:1340
 print_cpu_stall kernel/rcu/tree.c:1478 [inline]
 check_cpu_stall kernel/rcu/tree.c:1550 [inline]
 __rcu_pending kernel/rcu/tree.c:3293 [inline]
 rcu_pending kernel/rcu/tree.c:3336 [inline]
 rcu_check_callbacks.cold+0x62d/0xe19 kernel/rcu/tree.c:2682
 update_process_times+0x2a/0x70 kernel/time/timer.c:1650
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:168
 tick_sched_timer+0xfc/0x290 kernel/time/tick-sched.c:1278
 __run_hrtimer kernel/time/hrtimer.c:1401 [inline]
 __hrtimer_run_queues+0x3f6/0xe60 kernel/time/hrtimer.c:1463
 hrtimer_interrupt+0x32a/0x930 kernel/time/hrtimer.c:1521
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1067 [inline]
 smp_apic_timer_interrupt+0x10c/0x550 arch/x86/kernel/apic/apic.c:1092
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894
 </IRQ>
RIP: 0010:rep_nop arch/x86/include/asm/processor.h:665 [inline]
RIP: 0010:cpu_relax arch/x86/include/asm/processor.h:670 [inline]
RIP: 0010:pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:438 [inline]
RIP: 0010:__pv_queued_spin_lock_slowpath+0x3a4/0xae0 kernel/locking/qspinlock.c:474
Code: 48 89 eb c6 45 01 01 41 bc 00 80 00 00 48 c1 e9 03 83 e3 07 41 be 01 00 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8d 2c 01 eb 0c <f3> 90 41 83 ec 01 0f 84 38 04 00 00 41 0f b6 45 00 38 d8 7f 08 84
RSP: 0018:ffff88805927f910 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000003 RBX: 0000000000000000 RCX: 1ffffffff140412c
RDX: 0000000000000001 RSI: ffffffff81677df5 RDI: 0000000000000286
RBP: ffffffff8a020960 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000001bcc
R13: fffffbfff140412c R14: 0000000000000001 R15: ffff8880ba12bd80
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:679 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:53 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:88 [inline]
 do_raw_spin_lock+0x189/0x220 kernel/locking/spinlock_debug.c:113
 spin_lock include/linux/spinlock.h:329 [inline]
 free_huge_page+0x482/0xd20 mm/hugetlb.c:1276
 __put_page+0xe2/0x3a0 mm/swap.c:112
 put_page include/linux/mm.h:963 [inline]
 gather_surplus_pages mm/hugetlb.c:1792 [inline]
 hugetlb_acct_memory+0x77f/0xba0 mm/hugetlb.c:3111
 hugetlb_reserve_pages+0x47f/0x650 mm/hugetlb.c:4539
 hugetlbfs_file_mmap+0x2e4/0x4a0 fs/hugetlbfs/inode.c:164
 call_mmap include/linux/fs.h:1826 [inline]
 mmap_region+0xc94/0x16b0 mm/mmap.c:1757
 do_mmap+0x8e8/0x1080 mm/mmap.c:1530
 do_mmap_pgoff include/linux/mm.h:2326 [inline]
 vm_mmap_pgoff+0x197/0x200 mm/util.c:357
 ksys_mmap_pgoff+0x42e/0x5a0 mm/mmap.c:1580
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45e219
Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f0fb6206c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 000000000045e219
RDX: 0000000000000000 RSI: 0000000000e7e000 RDI: 0000000020000000
RBP: 000000000119bfd8 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000040031 R11: 0000000000000246 R12: 000000000119bf8c
R13: 00007fff77a88a1f R14: 00007f0fb62079c0 R15: 000000000119bf8c