2 files changed, 13 insertions, 4 deletions

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index e82488d3f0ba..a4c9cf0bf70b 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -249,7 +249,7 @@ static void native_apic_write_dummy(u32 reg, u32 v)
 
 static u32 native_apic_read_dummy(u32 reg)
 {
-        WARN_ON_ONCE((cpu_has_apic || !disable_apic));
+        WARN_ON_ONCE((cpu_has_apic && !disable_apic));
         return 0;
 }
 
@@ -1609,6 +1609,13 @@ void __init init_apic_mappings(void)
         new_apicid = read_apic_id();
         if (boot_cpu_physical_apicid != new_apicid) {
                 boot_cpu_physical_apicid = new_apicid;
+                /*
+                 * yeah -- we lie about apic_version
+                 * in case if apic was disabled via boot option
+                 * but it's not a problem for SMP compiled kernel
+                 * since smp_sanity_check is prepared for such a case
+                 * and disable smp mode
+                 */
                 apic_version[new_apicid] =
                          GET_APIC_VERSION(apic_read(APIC_LVR));
         }
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index d2e8de958156..7c80007ea5f7 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -992,10 +992,12 @@ static int __init smp_sanity_check(unsigned max_cpus)
          */
         if (APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid]) &&
             !cpu_has_apic) {
-                printk(KERN_ERR "BIOS bug, local APIC #%d not detected!...\n",
-                        boot_cpu_physical_apicid);
-                printk(KERN_ERR "... forcing use of dummy APIC emulation."
+                if (!disable_apic) {
+                        pr_err("BIOS bug, local APIC #%d not detected!...\n",
+                                boot_cpu_physical_apicid);
+                        pr_err("... forcing use of dummy APIC emulation."
                                 "(tell your hw vendor)\n");
+                }
                 smpboot_clear_io_apic();
                 arch_disable_smp_support();
                 return -1;