1 files changed, 15 insertions, 1 deletions

diff --git a/mm/memory.c b/mm/memory.c
index 5b744b30a195..dd8de96f5547 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1900,12 +1900,26 @@ int vm_insert_pfn_prot(struct vm_area_struct *vma, unsigned long addr,
 }
 EXPORT_SYMBOL(vm_insert_pfn_prot);
 
+static bool vm_mixed_ok(struct vm_area_struct *vma, pfn_t pfn)
+{
+        /* these checks mirror the abort conditions in vm_normal_page */
+        if (vma->vm_flags & VM_MIXEDMAP)
+                return true;
+        if (pfn_t_devmap(pfn))
+                return true;
+        if (pfn_t_special(pfn))
+                return true;
+        if (is_zero_pfn(pfn_t_to_pfn(pfn)))
+                return true;
+        return false;
+}
+
 static int __vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
                         pfn_t pfn, bool mkwrite)
 {
         pgprot_t pgprot = vma->vm_page_prot;
 
-        BUG_ON(!(vma->vm_flags & VM_MIXEDMAP));
+        BUG_ON(!vm_mixed_ok(vma, pfn));
 
         if (addr < vma->vm_start || addr >= vma->vm_end)
                 return -EFAULT;