MIPS: IRQ: Add stackoverflow detection

Add stackoverflow detection to mips arch

Signed-off-by: Adam Jiang <jiang.adam@gmail.com>
Cc: dmitri.vorobiev@movial.com
Cc: wuzhangjin@gmail.com
Cc: ddaney@caviumnetworks.com
Cc: peterz@infradead.org
Cc: fweisbec@gmail.com
Cc: tj@kernel.org
Cc: tglx@linutronix.de
Cc: mingo@elte.hu
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/1559/
Patchwork: https://patchwork.linux-mips.org/patch/1651/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 24 insertions, 0 deletions

diff --git a/arch/mips/kernel/irq.c b/arch/mips/kernel/irq.c
index c6345f579a8a..4f93db58a79e 100644
--- a/arch/mips/kernel/irq.c
+++ b/arch/mips/kernel/irq.c
@@ -151,6 +151,29 @@ void __init init_IRQ(void)
 #endif
 }
 
+#ifdef DEBUG_STACKOVERFLOW
+static inline void check_stack_overflow(void)
+{
+        unsigned long sp;
+
+        __asm__ __volatile__("move %0, $sp" : "=r" (sp));
+        sp &= THREAD_MASK;
+
+        /*
+         * Check for stack overflow: is there less than STACK_WARN free?
+         * STACK_WARN is defined as 1/8 of THREAD_SIZE by default.
+         */
+        if (unlikely(sp < (sizeof(struct thread_info) + STACK_WARN))) {
+                printk("do_IRQ: stack overflow: %ld\n",
+                       sp - sizeof(struct thread_info));
+                dump_stack();
+        }
+}
+#else
+static inline void check_stack_overflow(void) {}
+#endif
+
+
 /*
  * do_IRQ handles all normal device IRQ's (the special
  * SMP cross-CPU interrupts have their own specific
@@ -159,6 +182,7 @@ void __init init_IRQ(void)
 void __irq_entry do_IRQ(unsigned int irq)
 {
         irq_enter();
+        check_stack_overflow();
         __DO_IRQ_SMTC_HOOK(irq);
         generic_handle_irq(irq);
         irq_exit();