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>

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index b700c9a106442f72fe408f8423b7c1eb477b9c08..a778e221ccfb13d9d9f7e9a76ffc42613dcb57e2 100644 (file)
--- a/arch/x86/kernel/smpboot.c
+++ b/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 (maxlvt > 3)                 /* Due to the Pentium erratum 3AP.  */
-               apic_write(APIC_ESR, 0);
-       accept_status = (apic_read(APIC_ESR) & 0xEF);
+       if (APIC_INTEGRATED(apic_version[phys_apicid])) {
+               maxlvt = lapic_get_maxlvt();
+               if (maxlvt > 3)                 /* Due to the Pentium erratum 3AP.  */
+                       apic_write(APIC_ESR, 0);
+               accept_status = (apic_read(APIC_ESR) & 0xEF);
+       }
        pr_debug("NMI sent.\n");
 
        if (send_status)