1 files changed, 27 insertions, 5 deletions

diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
index ed34f5e35999..5c4ee422590e 100644
--- a/arch/x86/mm/pgtable.c
+++ b/arch/x86/mm/pgtable.c
@@ -1,4 +1,5 @@
 #include <linux/mm.h>
+#include <linux/gfp.h>
 #include <asm/pgalloc.h>
 #include <asm/pgtable.h>
 #include <asm/tlb.h>
@@ -6,6 +7,14 @@
 
 #define PGALLOC_GFP GFP_KERNEL | __GFP_NOTRACK | __GFP_REPEAT | __GFP_ZERO
 
+#ifdef CONFIG_HIGHPTE
+#define PGALLOC_USER_GFP __GFP_HIGHMEM
+#else
+#define PGALLOC_USER_GFP 0
+#endif
+
+gfp_t __userpte_alloc_gfp = PGALLOC_GFP | PGALLOC_USER_GFP;
+
 pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
 {
         return (pte_t *)__get_free_page(PGALLOC_GFP);
@@ -15,16 +24,29 @@ pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
 {
         struct page *pte;
 
-#ifdef CONFIG_HIGHPTE
-        pte = alloc_pages(PGALLOC_GFP | __GFP_HIGHMEM, 0);
-#else
-        pte = alloc_pages(PGALLOC_GFP, 0);
-#endif
+        pte = alloc_pages(__userpte_alloc_gfp, 0);
         if (pte)
                 pgtable_page_ctor(pte);
         return pte;
 }
 
+static int __init setup_userpte(char *arg)
+{
+        if (!arg)
+                return -EINVAL;
+
+        /*
+         * "userpte=nohigh" disables allocation of user pagetables in
+         * high memory.
+         */
+        if (strcmp(arg, "nohigh") == 0)
+                __userpte_alloc_gfp &= ~__GFP_HIGHMEM;
+        else
+                return -EINVAL;
+        return 0;
+}
+early_param("userpte", setup_userpte);
+
 void ___pte_free_tlb(struct mmu_gather *tlb, struct page *pte)
 {
         pgtable_page_dtor(pte);