x86: Support PAT bit in pagetable dump for lower levels

Dumping page table protection bits is not correct for entries on levels
2 and 3 regarding the PAT bit, which is at a different position as on
level 4.

Based-on-patch-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stefan.bader@canonical.com
Cc: xen-devel@lists.xensource.com
Cc: konrad.wilk@oracle.com
Cc: ville.syrjala@linux.intel.com
Cc: david.vrabel@citrix.com
Cc: jbeulich@suse.com
Cc: toshi.kani@hp.com
Cc: plagnioj@jcrosoft.com
Cc: tomi.valkeinen@ti.com
Cc: bhelgaas@google.com
Link: http://lkml.kernel.org/r/1415019724-4317-16-git-send-email-jgross@suse.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/x86/mm/dump_pagetables.c

@@ -126,7 +126,7 @@ static void printk_prot(struct seq_file *m, pgprot_t prot, int level, bool dmsg)
 
 	if (!pgprot_val(prot)) {
 		/* Not present */
-		pt_dump_cont_printf(m, dmsg, "                          ");
+		pt_dump_cont_printf(m, dmsg, "                              ");
 	} else {
 		if (pr & _PAGE_USER)
 			pt_dump_cont_printf(m, dmsg, "USR ");
@@ -145,18 +145,16 @@ static void printk_prot(struct seq_file *m, pgprot_t prot, int level, bool dmsg)
 		else
 			pt_dump_cont_printf(m, dmsg, "    ");
 
-		/* Bit 9 has a different meaning on level 3 vs 4 */
-		if (level <= 3) {
-			if (pr & _PAGE_PSE)
-				pt_dump_cont_printf(m, dmsg, "PSE ");
-			else
-				pt_dump_cont_printf(m, dmsg, "    ");
-		} else {
-			if (pr & _PAGE_PAT)
-				pt_dump_cont_printf(m, dmsg, "pat ");
-			else
-				pt_dump_cont_printf(m, dmsg, "    ");
-		}
+		/* Bit 7 has a different meaning on level 3 vs 4 */
+		if (level <= 3 && pr & _PAGE_PSE)
+			pt_dump_cont_printf(m, dmsg, "PSE ");
+		else
+			pt_dump_cont_printf(m, dmsg, "    ");
+		if ((level == 4 && pr & _PAGE_PAT) ||
+		    ((level == 3 || level == 2) && pr & _PAGE_PAT_LARGE))
+			pt_dump_cont_printf(m, dmsg, "pat ");
+		else
+			pt_dump_cont_printf(m, dmsg, "    ");
 		if (pr & _PAGE_GLOBAL)
 			pt_dump_cont_printf(m, dmsg, "GLB ");
 		else