x86: remove double-checking empty zero pages debug

[sfrench/cifs-2.6.git] / arch / x86 / mm / init_64.c

diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index a4a9cccdd4f2d5c012119e60489eedbb05c0af39..6dbb0035c57aa7c4059f0b157ed7ec1bfbe6f659 100644 (file)
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -171,6 +171,33 @@ set_pte_phys(unsigned long vaddr, unsigned long phys, pgprot_t prot)
        __flush_tlb_one(vaddr);
 }
 
+/*
+ * The head.S code sets up the kernel high mapping from:
+ * __START_KERNEL_map to __START_KERNEL_map + KERNEL_TEXT_SIZE
+ *
+ * phys_addr holds the negative offset to the kernel, which is added
+ * to the compile time generated pmds. This results in invalid pmds up
+ * to the point where we hit the physaddr 0 mapping.
+ *
+ * We limit the mappings to the region from _text to _end.  _end is
+ * rounded up to the 2MB boundary. This catches the invalid pmds as
+ * well, as they are located before _text:
+ */
+void __init cleanup_highmap(void)
+{
+       unsigned long vaddr = __START_KERNEL_map;
+       unsigned long end = round_up((unsigned long)_end, PMD_SIZE) - 1;
+       pmd_t *pmd = level2_kernel_pgt;
+       pmd_t *last_pmd = pmd + PTRS_PER_PMD;
+
+       for (; pmd < last_pmd; pmd++, vaddr += PMD_SIZE) {
+               if (!pmd_present(*pmd))
+                       continue;
+               if (vaddr < (unsigned long) _text || vaddr > end)
+                       set_pmd(pmd, __pmd(0));
+       }
+}
+
 /* NOTE: this is meant to be run only at boot */
 void __init
 __set_fixmap(enum fixed_addresses idx, unsigned long phys, pgprot_t prot)
@@ -488,14 +515,6 @@ void __init mem_init(void)
 
        /* clear_bss() already clear the empty_zero_page */
 
-       /* temporary debugging - double check it's true: */
-       {
-               int i;
-
-               for (i = 0; i < 1024; i++)
-                       WARN_ON_ONCE(empty_zero_page[i]);
-       }
-
        reservedpages = 0;
 
        /* this will put all low memory onto the freelists */