1 files changed, 18 insertions, 1 deletions

diff --git a/arch/x86_64/kernel/smpboot.c b/arch/x86_64/kernel/smpboot.c
index 571a55462fa0..b969ee128728 100644
--- a/arch/x86_64/kernel/smpboot.c
+++ b/arch/x86_64/kernel/smpboot.c
@@ -508,9 +508,22 @@ void __cpuinit start_secondary(void)
         set_cpu_sibling_map(smp_processor_id());
 
         /*
+         * We need to hold call_lock, so there is no inconsistency
+         * between the time smp_call_function() determines number of
+         * IPI receipients, and the time when the determination is made
+         * for which cpus receive the IPI in genapic_flat.c. Holding this
+         * lock helps us to not include this cpu in a currently in progress
+         * smp_call_function().
+         */
+        lock_ipi_call_lock();
+
+        /*
          * Allow the master to continue.
          */
         cpu_set(smp_processor_id(), cpu_online_map);
+        per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE;
+        unlock_ipi_call_lock();
+
         mb();
 
         /* Wait for TSC sync to not schedule things before.
@@ -1038,6 +1051,7 @@ void __init smp_prepare_boot_cpu(void)
         cpu_set(me, cpu_callout_map);
         cpu_set(0, cpu_sibling_map[0]);
         cpu_set(0, cpu_core_map[0]);
+        per_cpu(cpu_state, me) = CPU_ONLINE;
 }
 
 /*
@@ -1066,6 +1080,7 @@ int __cpuinit __cpu_up(unsigned int cpu)
                 return -ENOSYS;
         }
 
+        per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
         /* Boot it! */
         err = do_boot_cpu(cpu, apicid);
         if (err < 0) {
@@ -1170,8 +1185,10 @@ void __cpu_die(unsigned int cpu)
 
         for (i = 0; i < 10; i++) {
                 /* They ack this in play_dead by setting CPU_DEAD */
-                if (per_cpu(cpu_state, cpu) == CPU_DEAD)
+                if (per_cpu(cpu_state, cpu) == CPU_DEAD) {
+                        printk ("CPU %d is now offline\n", cpu);
                         return;
+                }
                 current->state = TASK_UNINTERRUPTIBLE;
                 schedule_timeout(HZ/10);
         }