3 files changed, 45 insertions, 6 deletions

diff --git a/arch/x86_64/kernel/io_apic.c b/arch/x86_64/kernel/io_apic.c
index 0e89ae7e7b22..fe429e5d6b29 100644
--- a/arch/x86_64/kernel/io_apic.c
+++ b/arch/x86_64/kernel/io_apic.c
@@ -63,7 +63,7 @@ int timer_over_8254 __initdata = 1;
 static struct { int pin, apic; } ioapic_i8259 = { -1, -1 };
 
 static DEFINE_SPINLOCK(ioapic_lock);
-static DEFINE_SPINLOCK(vector_lock);
+DEFINE_SPINLOCK(vector_lock);
 
 /*
  * # of IRQ routing registers
@@ -618,6 +618,9 @@ static int __assign_irq_vector(int irq, cpumask_t mask, cpumask_t *result)
 
         BUG_ON((unsigned)irq >= NR_IRQ_VECTORS);
 
+        /* Only try and allocate irqs on cpus that are present */
+        cpus_and(mask, mask, cpu_online_map);
+
         if (irq_vector[irq] > 0)
                 old_vector = irq_vector[irq];
         if (old_vector > 0) {
@@ -627,11 +630,12 @@ static int __assign_irq_vector(int irq, cpumask_t mask, cpumask_t *result)
         }
 
         for_each_cpu_mask(cpu, mask) {
-                cpumask_t domain;
+                cpumask_t domain, new_mask;
                 int new_cpu;
                 int vector, offset;
 
                 domain = vector_allocation_domain(cpu);
+                cpus_and(new_mask, domain, cpu_online_map);
 
                 vector = current_vector;
                 offset = current_offset;
@@ -646,18 +650,20 @@ next:
                         continue;
                 if (vector == IA32_SYSCALL_VECTOR)
                         goto next;
-                for_each_cpu_mask(new_cpu, domain)
+                for_each_cpu_mask(new_cpu, new_mask)
                         if (per_cpu(vector_irq, new_cpu)[vector] != -1)
                                 goto next;
                 /* Found one! */
                 current_vector = vector;
                 current_offset = offset;
                 if (old_vector >= 0) {
+                        cpumask_t old_mask;
                         int old_cpu;
-                        for_each_cpu_mask(old_cpu, irq_domain[irq])
+                        cpus_and(old_mask, irq_domain[irq], cpu_online_map);
+                        for_each_cpu_mask(old_cpu, old_mask)
                                 per_cpu(vector_irq, old_cpu)[old_vector] = -1;
                 }
-                for_each_cpu_mask(new_cpu, domain)
+                for_each_cpu_mask(new_cpu, new_mask)
                         per_cpu(vector_irq, new_cpu)[vector] = irq;
                 irq_vector[irq] = vector;
                 irq_domain[irq] = domain;
@@ -678,6 +684,32 @@ static int assign_irq_vector(int irq, cpumask_t mask, cpumask_t *result)
         return vector;
 }
 
+void __setup_vector_irq(int cpu)
+{
+        /* Initialize vector_irq on a new cpu */
+        /* This function must be called with vector_lock held */
+        unsigned long flags;
+        int irq, vector;
+
+
+        /* Mark the inuse vectors */
+        for (irq = 0; irq < NR_IRQ_VECTORS; ++irq) {
+                if (!cpu_isset(cpu, irq_domain[irq]))
+                        continue;
+                vector = irq_vector[irq];
+                per_cpu(vector_irq, cpu)[vector] = irq;
+        }
+        /* Mark the free vectors */
+        for (vector = 0; vector < NR_VECTORS; ++vector) {
+                irq = per_cpu(vector_irq, cpu)[vector];
+                if (irq < 0)
+                        continue;
+                if (!cpu_isset(cpu, irq_domain[irq]))
+                        per_cpu(vector_irq, cpu)[vector] = -1;
+        }
+}
+
+
 extern void (*interrupt[NR_IRQS])(void);
 
 static struct irq_chip ioapic_chip;
diff --git a/arch/x86_64/kernel/smpboot.c b/arch/x86_64/kernel/smpboot.c
index 7b7a6870288a..62c2e747af58 100644
--- a/arch/x86_64/kernel/smpboot.c
+++ b/arch/x86_64/kernel/smpboot.c
@@ -581,12 +581,16 @@ void __cpuinit start_secondary(void)
          * smp_call_function().
          */
         lock_ipi_call_lock();
+        spin_lock(&vector_lock);
 
+        /* Setup the per cpu irq handling data structures */
+        __setup_vector_irq(smp_processor_id());
         /*
          * Allow the master to continue.
          */
         cpu_set(smp_processor_id(), cpu_online_map);
         per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE;
+        spin_unlock(&vector_lock);
         unlock_ipi_call_lock();
 
         cpu_idle();
@@ -799,7 +803,6 @@ static int __cpuinit do_boot_cpu(int cpu, int apicid)
                                 cpu, node);
         }
 
-
         alternatives_smp_switch(1);
 
         c_idle.idle = get_idle_for_cpu(cpu);
@@ -1246,8 +1249,10 @@ int __cpu_disable(void)
         local_irq_disable();
         remove_siblinginfo(cpu);
 
+        spin_lock(&vector_lock);
         /* It's now safe to remove this processor from the online map */
         cpu_clear(cpu, cpu_online_map);
+        spin_unlock(&vector_lock);
         remove_cpu_from_maps();
         fixup_irqs(cpu_online_map);
         return 0;
diff --git a/include/asm-x86_64/hw_irq.h b/include/asm-x86_64/hw_irq.h
index 792dd52fcd70..179cce755aa7 100644
--- a/include/asm-x86_64/hw_irq.h
+++ b/include/asm-x86_64/hw_irq.h
@@ -76,6 +76,8 @@
 #ifndef __ASSEMBLY__
 typedef int vector_irq_t[NR_VECTORS];
 DECLARE_PER_CPU(vector_irq_t, vector_irq);
+extern void __setup_vector_irq(int cpu);
+extern spinlock_t vector_lock;
 
 /*
  * Various low-level irq details needed by irq.c, process.c,