1 files changed, 15 insertions, 7 deletions

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 7dd9b0b85e4e..5eb96c7c8d7a 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -76,6 +76,14 @@ static inline int valid_vcpu(int n)
         return likely(n >= 0 && n < KVM_MAX_VCPUS);
 }
 
+static inline int is_mmio_pfn(pfn_t pfn)
+{
+        if (pfn_valid(pfn))
+                return PageReserved(pfn_to_page(pfn));
+
+        return true;
+}
+
 /*
  * Switches to specified vcpu, until a matching vcpu_put()
  */
@@ -740,7 +748,7 @@ pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
                 }
 
                 pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
-                BUG_ON(pfn_valid(pfn));
+                BUG_ON(!is_mmio_pfn(pfn));
         } else
                 pfn = page_to_pfn(page[0]);
 
@@ -754,10 +762,10 @@ struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
         pfn_t pfn;
 
         pfn = gfn_to_pfn(kvm, gfn);
-        if (pfn_valid(pfn))
+        if (!is_mmio_pfn(pfn))
                 return pfn_to_page(pfn);
 
-        WARN_ON(!pfn_valid(pfn));
+        WARN_ON(is_mmio_pfn(pfn));
 
         get_page(bad_page);
         return bad_page;
@@ -773,7 +781,7 @@ EXPORT_SYMBOL_GPL(kvm_release_page_clean);
 
 void kvm_release_pfn_clean(pfn_t pfn)
 {
-        if (pfn_valid(pfn))
+        if (!is_mmio_pfn(pfn))
                 put_page(pfn_to_page(pfn));
 }
 EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
@@ -799,7 +807,7 @@ EXPORT_SYMBOL_GPL(kvm_set_page_dirty);
 
 void kvm_set_pfn_dirty(pfn_t pfn)
 {
-        if (pfn_valid(pfn)) {
+        if (!is_mmio_pfn(pfn)) {
                 struct page *page = pfn_to_page(pfn);
                 if (!PageReserved(page))
                         SetPageDirty(page);
@@ -809,14 +817,14 @@ EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
 
 void kvm_set_pfn_accessed(pfn_t pfn)
 {
-        if (pfn_valid(pfn))
+        if (!is_mmio_pfn(pfn))
                 mark_page_accessed(pfn_to_page(pfn));
 }
 EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
 
 void kvm_get_pfn(pfn_t pfn)
 {
-        if (pfn_valid(pfn))
+        if (!is_mmio_pfn(pfn))
                 get_page(pfn_to_page(pfn));
 }
 EXPORT_SYMBOL_GPL(kvm_get_pfn);