1 files changed, 2 insertions, 22 deletions
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index d283678..0fc25ae 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -102,28 +102,8 @@ static bool largepages_enabled = true;
 
 bool kvm_is_mmio_pfn(pfn_t pfn)
 {
-	if (pfn_valid(pfn)) {
-		int reserved;
-		struct page *tail = pfn_to_page(pfn);
-		struct page *head = compound_trans_head(tail);
-		reserved = PageReserved(head);
-		if (head != tail) {
-			/*
-			 * "head" is not a dangling pointer
-			 * (compound_trans_head takes care of that)
-			 * but the hugepage may have been splitted
-			 * from under us (and we may not hold a
-			 * reference count on the head page so it can
-			 * be reused before we run PageReferenced), so
-			 * we've to check PageTail before returning
-			 * what we just read.
-			 */
-			smp_rmb();
-			if (PageTail(tail))
-				return reserved;
-		}
-		return PageReserved(tail);
-	}
+	if (pfn_valid(pfn))
+		return PageReserved(pfn_to_page(pfn));
 
 	return true;
 }