3 files changed, 13 insertions, 5 deletions

diff --git a/arch/sh/Kconfig.debug b/arch/sh/Kconfig.debug
index b507b501f0cf..ab2f9f3c354c 100644
--- a/arch/sh/Kconfig.debug
+++ b/arch/sh/Kconfig.debug
@@ -86,6 +86,14 @@ config 4KSTACKS
           on the VM subsystem for higher order allocations. This option
           will also use IRQ stacks to compensate for the reduced stackspace.
 
+config IRQSTACKS
+        bool "Use separate kernel stacks when processing interrupts"
+        depends on DEBUG_KERNEL
+        help
+          If you say Y here the kernel will use separate kernel stacks
+          for handling hard and soft interrupts.  This can help avoid
+          overflowing the process kernel stacks.
+
 config SH_KGDB
         bool "Include KGDB kernel debugger"
         select FRAME_POINTER
diff --git a/arch/sh/kernel/irq.c b/arch/sh/kernel/irq.c
index 4b49d03ffbd2..348da194ec99 100644
--- a/arch/sh/kernel/irq.c
+++ b/arch/sh/kernel/irq.c
@@ -69,7 +69,7 @@ unlock:
 }
 #endif
 
-#ifdef CONFIG_4KSTACKS
+#ifdef CONFIG_IRQSTACKS
 /*
  * per-CPU IRQ handling contexts (thread information and stack)
  */
@@ -85,7 +85,7 @@ static union irq_ctx *softirq_ctx[NR_CPUS] __read_mostly;
 asmlinkage int do_IRQ(unsigned int irq, struct pt_regs *regs)
 {
         struct pt_regs *old_regs = set_irq_regs(regs);
-#ifdef CONFIG_4KSTACKS
+#ifdef CONFIG_IRQSTACKS
         union irq_ctx *curctx, *irqctx;
 #endif
 
@@ -109,7 +109,7 @@ asmlinkage int do_IRQ(unsigned int irq, struct pt_regs *regs)
 
         irq = irq_demux(evt2irq(irq));
 
-#ifdef CONFIG_4KSTACKS
+#ifdef CONFIG_IRQSTACKS
         curctx = (union irq_ctx *)current_thread_info();
         irqctx = hardirq_ctx[smp_processor_id()];
 
@@ -157,7 +157,7 @@ asmlinkage int do_IRQ(unsigned int irq, struct pt_regs *regs)
         return 1;
 }
 
-#ifdef CONFIG_4KSTACKS
+#ifdef CONFIG_IRQSTACKS
 static char softirq_stack[NR_CPUS * THREAD_SIZE]
                 __attribute__((__section__(".bss.page_aligned")));
 
diff --git a/include/asm-sh/irq.h b/include/asm-sh/irq.h
index c61d902b8bff..11850f65c922 100644
--- a/include/asm-sh/irq.h
+++ b/include/asm-sh/irq.h
@@ -41,7 +41,7 @@ static inline int generic_irq_demux(int irq)
 #define irq_canonicalize(irq)   (irq)
 #define irq_demux(irq)          sh_mv.mv_irq_demux(irq)
 
-#ifdef CONFIG_4KSTACKS
+#ifdef CONFIG_IRQSTACKS
 extern void irq_ctx_init(int cpu);
 extern void irq_ctx_exit(int cpu);
 # define __ARCH_HAS_DO_SOFTIRQ