KVM: do not release the error pfn

After commit a2766325cf9f9, the error pfn is replaced by the
error code, it need not be released anymore

[ The patch has been compiling tested for powerpc ]

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 93d3c6e..eafba99 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -102,9 +102,6 @@
 
 bool kvm_is_mmio_pfn(pfn_t pfn)
 {
-	if (is_error_pfn(pfn))
-		return false;
-
 	if (pfn_valid(pfn)) {
 		int reserved;
 		struct page *tail = pfn_to_page(pfn);
@@ -1165,11 +1162,14 @@
 
 static struct page *kvm_pfn_to_page(pfn_t pfn)
 {
-	WARN_ON(kvm_is_mmio_pfn(pfn));
-
-	if (is_error_pfn(pfn) || kvm_is_mmio_pfn(pfn))
+	if (is_error_pfn(pfn))
 		return KVM_ERR_PTR_BAD_PAGE;
 
+	if (kvm_is_mmio_pfn(pfn)) {
+		WARN_ON(1);
+		return KVM_ERR_PTR_BAD_PAGE;
+	}
+
 	return pfn_to_page(pfn);
 }
 
@@ -1193,7 +1193,9 @@
 
 void kvm_release_pfn_clean(pfn_t pfn)
 {
-	if (!is_error_pfn(pfn) && !kvm_is_mmio_pfn(pfn))
+	WARN_ON(is_error_pfn(pfn));
+
+	if (!kvm_is_mmio_pfn(pfn))
 		put_page(pfn_to_page(pfn));
 }
 EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);