diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index afe1d54f980c..673e968df3cf 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -59,6 +59,7 @@
 #include <asm/page.h>
 #include <asm/init.h>
 #include <asm/pat.h>
+#include <asm/smp.h>
 
 #include <asm/xen/hypercall.h>
 #include <asm/xen/hypervisor.h>
@@ -1231,7 +1232,7 @@ static void xen_flush_tlb_others(const struct cpumask *cpus,
 {
 	struct {
 		struct mmuext_op op;
-		DECLARE_BITMAP(mask, NR_CPUS);
+		DECLARE_BITMAP(mask, num_processors);
 	} *args;
 	struct multicall_space mcs;
 
diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c
index 41038c01de40..b4533a86d7e4 100644
--- a/arch/x86/xen/smp.c
+++ b/arch/x86/xen/smp.c
@@ -205,11 +205,18 @@ static void __init xen_smp_prepare_boot_cpu(void)
 static void __init xen_smp_prepare_cpus(unsigned int max_cpus)
 {
 	unsigned cpu;
+	unsigned int i;
 
 	xen_init_lock_cpu(0);
 
 	smp_store_cpu_info(0);
 	cpu_data(0).x86_max_cores = 1;
+
+	for_each_possible_cpu(i) {
+		zalloc_cpumask_var(&per_cpu(cpu_sibling_map, i), GFP_KERNEL);
+		zalloc_cpumask_var(&per_cpu(cpu_core_map, i), GFP_KERNEL);
+		zalloc_cpumask_var(&per_cpu(cpu_llc_shared_map, i), GFP_KERNEL);
+	}
 	set_cpu_sibling_map(0);
 
 	if (xen_smp_intr_init(0))