Revert "x86: fix pmd_bad and pud_bad to support huge pages"

This reverts commit cded932.

Arjan bisected down a boot-time hang to this, saying:
  ".. it prevents the kernel to finish booting on my (Penryn based)
   laptop.  The boot stops right after freeing the init memory."

and while it's not clear exactly what triggers it, at this stage we're
better off just reverting it while Ingo tries to figure out what went
wrong.

Requested-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Hans Rosenfeld <hans.rosenfeld@amd.com>
Cc: Nish Aravamudan <nish.aravamudan@gmail.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/asm-x86/pgtable_32.h

@@ -91,9 +91,7 @@ extern unsigned long pg0[];
 /* To avoid harmful races, pmd_none(x) should check only the lower when PAE */
 #define pmd_none(x)	(!(unsigned long)pmd_val(x))
 #define pmd_present(x)	(pmd_val(x) & _PAGE_PRESENT)
-#define	pmd_bad(x)	((pmd_val(x) \
-			  & ~(PAGE_MASK | _PAGE_USER | _PAGE_PSE | _PAGE_NX)) \
-			 != _KERNPG_TABLE)
+#define	pmd_bad(x)	((pmd_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE)
 
 
 #define pages_to_mb(x) ((x) >> (20-PAGE_SHIFT))

include/asm-x86/pgtable_64.h

@@ -153,14 +153,12 @@ static inline unsigned long pgd_bad(pgd_t pgd)
 
 static inline unsigned long pud_bad(pud_t pud)
 {
-	return pud_val(pud) &
-		~(PTE_MASK | _KERNPG_TABLE | _PAGE_USER | _PAGE_PSE | _PAGE_NX);
+	return pud_val(pud) & ~(PTE_MASK | _KERNPG_TABLE | _PAGE_USER);
 }
 
 static inline unsigned long pmd_bad(pmd_t pmd)
 {
-	return pmd_val(pmd) &
-		~(PTE_MASK | _KERNPG_TABLE | _PAGE_USER | _PAGE_PSE | _PAGE_NX);
+	return pmd_val(pmd) & ~(PTE_MASK | _KERNPG_TABLE | _PAGE_USER);
 }
 
 #define pte_none(x)	(!pte_val(x))