x86: smpboot - check if we have ESR register in wakeup_secondary_cpu

We should check if we have ESR register before reading from it.

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: "Maciej W. Rozycki" <macro@linux-mips.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/kernel/smpboot.c

@@ -599,10 +599,12 @@ wakeup_secondary_cpu(int logical_apicid, unsigned long start_eip)
 	 * Give the other CPU some time to accept the IPI.
 	 */
 	udelay(200);
-	maxlvt = lapic_get_maxlvt();
+	if (APIC_INTEGRATED(apic_version[phys_apicid])) {
-	if (maxlvt > 3)			/* Due to the Pentium erratum 3AP.  */
+		maxlvt = lapic_get_maxlvt();
-		apic_write(APIC_ESR, 0);
+		if (maxlvt > 3)			/* Due to the Pentium erratum 3AP.  */
-	accept_status = (apic_read(APIC_ESR) & 0xEF);
+			apic_write(APIC_ESR, 0);
+		accept_status = (apic_read(APIC_ESR) & 0xEF);
+	}
 	pr_debug("NMI sent.\n");
 
 	if (send_status)