1 files changed, 19 insertions, 14 deletions

diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index 3d68ef6d2266..de36c886cd38 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -704,21 +704,18 @@ int track_pfn_vma_copy(struct vm_area_struct *vma)
 int track_pfn_vma_new(struct vm_area_struct *vma, pgprot_t *prot,
                         unsigned long pfn, unsigned long size)
 {
+        resource_size_t paddr = (resource_size_t)pfn << PAGE_SHIFT;
         unsigned long flags;
-        resource_size_t paddr;
-        unsigned long vma_size = vma->vm_end - vma->vm_start;
 
-        if (is_linear_pfn_mapping(vma)) {
-                /* reserve the whole chunk starting from vm_pgoff */
-                paddr = (resource_size_t)vma->vm_pgoff << PAGE_SHIFT;
-                return reserve_pfn_range(paddr, vma_size, prot, 0);
-        }
+        /* reserve the whole chunk starting from paddr */
+        if (is_linear_pfn_mapping(vma))
+                return reserve_pfn_range(paddr, size, prot, 0);
 
         if (!pat_enabled)
                 return 0;
 
         /* for vm_insert_pfn and friends, we set prot based on lookup */
-        flags = lookup_memtype(pfn << PAGE_SHIFT);
+        flags = lookup_memtype(paddr);
         *prot = __pgprot((pgprot_val(vma->vm_page_prot) & (~_PAGE_CACHE_MASK)) |
                          flags);
 
@@ -728,20 +725,28 @@ int track_pfn_vma_new(struct vm_area_struct *vma, pgprot_t *prot,
 /*
  * untrack_pfn_vma is called while unmapping a pfnmap for a region.
  * untrack can be called for a specific region indicated by pfn and size or
- * can be for the entire vma (in which case size can be zero).
+ * can be for the entire vma (in which case pfn, size are zero).
  */
 void untrack_pfn_vma(struct vm_area_struct *vma, unsigned long pfn,
                         unsigned long size)
 {
         resource_size_t paddr;
-        unsigned long vma_size = vma->vm_end - vma->vm_start;
+        unsigned long prot;
 
-        if (is_linear_pfn_mapping(vma)) {
-                /* free the whole chunk starting from vm_pgoff */
-                paddr = (resource_size_t)vma->vm_pgoff << PAGE_SHIFT;
-                free_pfn_range(paddr, vma_size);
+        if (!is_linear_pfn_mapping(vma))
                 return;
+
+        /* free the chunk starting from pfn or the whole chunk */
+        paddr = (resource_size_t)pfn << PAGE_SHIFT;
+        if (!paddr && !size) {
+                if (follow_phys(vma, vma->vm_start, 0, &prot, &paddr)) {
+                        WARN_ON_ONCE(1);
+                        return;
+                }
+
+                size = vma->vm_end - vma->vm_start;
         }
+        free_pfn_range(paddr, size);
 }
 
 pgprot_t pgprot_writecombine(pgprot_t prot)