diff --git a/arch/i386/kernel/irq.c b/arch/i386/kernel/irq.c
index f3a9c78..248e922 100644
--- a/arch/i386/kernel/irq.c
+++ b/arch/i386/kernel/irq.c
@@ -42,8 +42,8 @@
 	u32                     stack[THREAD_SIZE/sizeof(u32)];
 };
 
-static union irq_ctx *hardirq_ctx[NR_CPUS];
-static union irq_ctx *softirq_ctx[NR_CPUS];
+static union irq_ctx *hardirq_ctx[NR_CPUS] __read_mostly;
+static union irq_ctx *softirq_ctx[NR_CPUS] __read_mostly;
 #endif
 
 /*
diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
index bfcec4c..40d4c14 100644
--- a/arch/powerpc/kernel/irq.c
+++ b/arch/powerpc/kernel/irq.c
@@ -380,8 +380,8 @@
 #endif /* CONFIG_PPC64 */
 
 #ifdef CONFIG_IRQSTACKS
-struct thread_info *softirq_ctx[NR_CPUS];
-struct thread_info *hardirq_ctx[NR_CPUS];
+struct thread_info *softirq_ctx[NR_CPUS] __read_mostly;
+struct thread_info *hardirq_ctx[NR_CPUS] __read_mostly;
 
 void irq_ctx_init(void)
 {