BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 9eb30067 P4D 9eb30067 PUD a6bdd067 PMD 0 
Oops: 0002 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 6825 Comm: syz-fuzzer Not tainted 5.9.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:update_pvclock_gtod arch/x86/kvm/x86.c:1742 [inline]
RIP: 0010:pvclock_gtod_notify+0x104/0x570 arch/x86/kvm/x86.c:7449
Code: 38 d0 7c 08 84 d2 0f 85 ab 03 00 00 8b 45 4c 48 8d 7b 10 48 89 fa 48 c1 ea 03 89 05 56 1a df 0a 48 b8 00 00 00 00 00 00 00 00 <00> 00 00 00 0f 85 23 04 00 00 48 8b 43 10 48 8d 7b 08 48 89 00 00
RSP: 0000:ffffc90001627b28 EFLAGS: 00010802
RAX: 0000000000000000 RBX: ffffffff8c973980 RCX: ffffffff815a14fb
RDX: 1ffffffff192e732 RSI: 0000000000000001 RDI: ffffffff8c973990
RBP: ffffffff89b35820 R08: 0000000000000000 R09: ffffffff8c5f3a1f
R10: fffffbfff18be743 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: ffffffff89ae98e0
FS:  000000c0000c1910(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000009ed5f000 CR4: 00000000001526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83
 update_pvclock_gtod kernel/time/timekeeping.c:581 [inline]
 timekeeping_update+0x28a/0x4a0 kernel/time/timekeeping.c:675
 timekeeping_advance+0x6ad/0xa40 kernel/time/timekeeping.c:2122
 tick_do_update_jiffies64.part.0+0x1ec/0x330 kernel/time/tick-sched.c:101
 tick_do_update_jiffies64 kernel/time/tick-sched.c:64 [inline]
 tick_sched_do_timer kernel/time/tick-sched.c:147 [inline]
 tick_sched_timer+0x236/0x2a0 kernel/time/tick-sched.c:1321
 __run_hrtimer kernel/time/hrtimer.c:1524 [inline]
 __hrtimer_run_queues+0x1d5/0xfc0 kernel/time/hrtimer.c:1588
 hrtimer_interrupt+0x32a/0x930 kernel/time/hrtimer.c:1650
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline]
 __sysvec_apic_timer_interrupt+0x142/0x5e0 arch/x86/kernel/apic/apic.c:1097
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:50 [inline]
 sysvec_apic_timer_interrupt+0x4c/0xf0 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581