1 files changed, 14 insertions, 7 deletions

diff --git a/mm/nommu.c b/mm/nommu.c
index ef8c62cec697..4462b6a3fcb9 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -39,7 +39,7 @@ struct page *mem_map;
 unsigned long max_mapnr;
 unsigned long num_physpages;
 unsigned long askedalloc, realalloc;
-atomic_t vm_committed_space = ATOMIC_INIT(0);
+atomic_long_t vm_committed_space = ATOMIC_LONG_INIT(0);
 int sysctl_overcommit_memory = OVERCOMMIT_GUESS; /* heuristic overcommit */
 int sysctl_overcommit_ratio = 50; /* default is 50% */
 int sysctl_max_map_count = DEFAULT_MAX_MAP_COUNT;
@@ -109,16 +109,23 @@ unsigned int kobjsize(const void *objp)
          * If the object we have should not have ksize performed on it,
          * return size of 0
          */
-        if (!objp || (unsigned long)objp >= memory_end || !((page = virt_to_page(objp))))
+        if (!objp || !virt_addr_valid(objp))
                 return 0;
 
+        page = virt_to_head_page(objp);
+
+        /*
+         * If the allocator sets PageSlab, we know the pointer came from
+         * kmalloc().
+         */
         if (PageSlab(page))
                 return ksize(objp);
 
-        BUG_ON(page->index < 0);
-        BUG_ON(page->index >= MAX_ORDER);
-
-        return (PAGE_SIZE << page->index);
+        /*
+         * The ksize() function is only guaranteed to work for pointers
+         * returned by kmalloc(). So handle arbitrary pointers here.
+         */
+        return PAGE_SIZE << compound_order(page);
 }
 
 /*
@@ -1410,7 +1417,7 @@ int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin)
          * cast `allowed' as a signed long because vm_committed_space
          * sometimes has a negative value
          */
-        if (atomic_read(&vm_committed_space) < (long)allowed)
+        if (atomic_long_read(&vm_committed_space) < (long)allowed)
                 return 0;
 error:
         vm_unacct_memory(pages);