x86/apic: remove read/write test in verify_local_apic()

index ad3639a..d54601e 100644
@@ -1105,13 +1105,13 @@ int __init verify_local_APIC(void)
 	/*
 	 * The two version reads above should print the same
 	 * numbers.  If the second one is different, then we
-	 * poke at a non-APIC.
+	 * are poking at a non-APIC region.
 	 */
 	if (reg1 != reg0)
 		return 0;
 
 	/*
-	 * Check if the version looks reasonably.
+	 * Check if the version looks reasonable.
 	 */
 	reg1 = GET_APIC_VERSION(reg0);
 	if (reg1 == 0x00 || reg1 == 0xff)

@@ -1121,21 +1121,17 @@ int __init verify_local_APIC(void)
 		return 0;
 
 	/*
-	 * The ID register is read/write in a real APIC.
+	 * Just print the APIC ID
+	 * Writing to it is not a reliable test - older processors
+	 * support it, while newer processors don't
 	 */
 	reg0 = apic_read(APIC_ID);
-	apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg0);
-	apic_write(APIC_ID, reg0 ^ apic->apic_id_mask);
-	reg1 = apic_read(APIC_ID);
-	apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg1);
-	apic_write(APIC_ID, reg0);
-	if (reg1 != (reg0 ^ apic->apic_id_mask))
-		return 0;
+	apic_printk(APIC_DEBUG, "Getting Local APIC ID: %x\n", reg0);
 
 	/*
 	 * The next two are just to see if we have sane values.
 	 * They're only really relevant if we're in Virtual Wire
-	 * compatibility mode, but most boxes are anymore.
+	 * compatibility mode, but most boxes aren't anymore.
 	 */
 	reg0 = apic_read(APIC_LVT0);
 	apic_printk(APIC_DEBUG, "Getting LVT0: %x\n", reg0);