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>
diff --git a/arch/mips/Kconfig.debug b/arch/mips/Kconfig.debug
index 43dc279..f437cd1 100644
--- a/arch/mips/Kconfig.debug
+++ b/arch/mips/Kconfig.debug
@@ -67,6 +67,15 @@
Normally, you will choose 'N' here.
+config DEBUG_STACKOVERFLOW
+ bool "Check for stack overflows"
+ depends on DEBUG_KERNEL
+ help
+ This option will cause messages to be printed if free stack space
+ drops below a certain limit(2GB on MIPS). The debugging option
+ provides another way to check stack overflow happened on kernel mode
+ stack usually caused by nested interruption.
+
config DEBUG_STACK_USAGE
bool "Enable stack utilization instrumentation"
depends on DEBUG_KERNEL
diff --git a/arch/mips/include/asm/thread_info.h b/arch/mips/include/asm/thread_info.h
index 70df9c0..d309556 100644
--- a/arch/mips/include/asm/thread_info.h
+++ b/arch/mips/include/asm/thread_info.h
@@ -83,6 +83,8 @@
#define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
#define THREAD_MASK (THREAD_SIZE - 1UL)
+#define STACK_WARN (THREAD_SIZE / 8)
+
#define __HAVE_ARCH_THREAD_INFO_ALLOCATOR
#ifdef CONFIG_DEBUG_STACK_USAGE
diff --git a/arch/mips/kernel/irq.c b/arch/mips/kernel/irq.c
index c6345f5..4f93db5 100644
--- a/arch/mips/kernel/irq.c
+++ b/arch/mips/kernel/irq.c
@@ -151,6 +151,29 @@
#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 __irq_entry do_IRQ(unsigned int irq)
{
irq_enter();
+ check_stack_overflow();
__DO_IRQ_SMTC_HOOK(irq);
generic_handle_irq(irq);
irq_exit();