From: Andrew Morton <akpm@linux-foundation.org>

In file included from arch/i386/mach-default/setup.c:5:
include/linux/smp.h: In function 'smp_call_function_single':
include/linux/smp.h:104: error: 'EBUSY' undeclared (first use in this function)
include/linux/smp.h:104: error: (Each undeclared identifier is reported only once
include/linux/smp.h:104: error: for each function it appears in.)

Cc: Andi Kleen <ak@suse.de>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/smp.h |    3 +++
 1 file changed, 3 insertions(+)

diff -puN include/linux/smp.h~let-smp_call_function_single-return-ebusy-on-up-fix include/linux/smp.h
--- a/include/linux/smp.h~let-smp_call_function_single-return-ebusy-on-up-fix
+++ a/include/linux/smp.h
@@ -9,12 +9,15 @@
 
 extern void cpu_idle(void);
 
+#include <linux/errno.h>
+
 #ifdef CONFIG_SMP
 
 #include <linux/preempt.h>
 #include <linux/kernel.h>
 #include <linux/compiler.h>
 #include <linux/thread_info.h>
+
 #include <asm/smp.h>
 
 /*
_