
void kvm_dec_notifier_count(struct kvm *kvm, unsigned long start,
				   unsigned long end)
{
	/*
	 * This sequence increase will notify the kvm page fault that
	 * the page that is going to be mapped in the spte could have
	 * been freed.
	 */
	kvm->mmu_notifier_seq++;
	smp_wmb();
	/*
	 * The above sequence increase must be visible before the
	 * below count decrease, which is ensured by the smp_wmb above
	 * in conjunction with the smp_rmb in mmu_notifier_retry().
	 */
	kvm->mmu_notifier_count--;

void kvm_dec_notifier_count(struct kvm *kvm, unsigned long start,
				   unsigned long end)
{
	 
	kvm->mmu_notifier_seq++;
	smp_wmb();
	 
	kvm->mmu_notifier_count--;