KVM: x86: return 0 in case kvm_mmu_memory_cache has min number of objects

The code tries to pre-allocate *min* number of objects, so it is ok to
return 0 when the kvm_mmu_memory_cache meets the requirement.
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/mmu.c

@@ -932,7 +932,7 @@ static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache,
 	while (cache->nobjs < ARRAY_SIZE(cache->objects)) {
 		obj = kmem_cache_zalloc(base_cache, GFP_KERNEL);
 		if (!obj)
-			return -ENOMEM;
+			return cache->nobjs >= min ? 0 : -ENOMEM;
 		cache->objects[cache->nobjs++] = obj;
 	}
 	return 0;
@@ -960,7 +960,7 @@ static int mmu_topup_memory_cache_page(struct kvm_mmu_memory_cache *cache,
 	while (cache->nobjs < ARRAY_SIZE(cache->objects)) {
 		page = (void *)__get_free_page(GFP_KERNEL_ACCOUNT);
 		if (!page)
-			return -ENOMEM;
+			return cache->nobjs >= min ? 0 : -ENOMEM;
 		cache->objects[cache->nobjs++] = page;
 	}
 	return 0;