sparc64: Run NMIs on the hardirq stack.

Otherwise we can overflow the main stack with the function tracer
enabled.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 19 insertions, 0 deletions

diff --git a/arch/sparc/kernel/kstack.h b/arch/sparc/kernel/kstack.h
index 5247283d1c03..53dfb92e09fb 100644
--- a/arch/sparc/kernel/kstack.h
+++ b/arch/sparc/kernel/kstack.h
@@ -61,4 +61,23 @@ check_magic:
 
 }
 
+static inline __attribute__((always_inline)) void *set_hardirq_stack(void)
+{
+        void *orig_sp, *sp = hardirq_stack[smp_processor_id()];
+
+        __asm__ __volatile__("mov %%sp, %0" : "=r" (orig_sp));
+        if (orig_sp < sp ||
+            orig_sp > (sp + THREAD_SIZE)) {
+                sp += THREAD_SIZE - 192 - STACK_BIAS;
+                __asm__ __volatile__("mov %0, %%sp" : : "r" (sp));
+        }
+
+        return orig_sp;
+}
+
+static inline __attribute__((always_inline)) void restore_hardirq_stack(void *orig_sp)
+{
+        __asm__ __volatile__("mov %0, %%sp" : : "r" (orig_sp));
+}
+
 #endif /* _KSTACK_H */