x86: move stack_start to smp.h

voyager would conflict with it, but the types are ultimately
compatible. So remove the extern definition from voyager_smp.c
in favour of the common one

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

3 files changed, 7 insertions, 13 deletions

diff --git a/arch/x86/kernel/smpboot_32.c b/arch/x86/kernel/smpboot_32.c
index 1eb7b73b45a3..ae25927f08c1 100644
--- a/arch/x86/kernel/smpboot_32.c
+++ b/arch/x86/kernel/smpboot_32.c
@@ -257,12 +257,6 @@ void __devinit initialize_secondary(void)
                 :"m" (current->thread.sp),"m" (current->thread.ip));
 }
 
-/* Static state in head.S used to set up a CPU */
-extern struct {
-        void * sp;
-        unsigned short ss;
-} stack_start;
-
 static inline void __inquire_remote_apic(int apicid)
 {
         unsigned i, regs[] = { APIC_ID >> 4, APIC_LVR >> 4, APIC_SPIV >> 4 };
diff --git a/arch/x86/mach-voyager/voyager_smp.c b/arch/x86/mach-voyager/voyager_smp.c
index 11b806c7ed94..4397235c2e30 100644
--- a/arch/x86/mach-voyager/voyager_smp.c
+++ b/arch/x86/mach-voyager/voyager_smp.c
@@ -520,13 +520,6 @@ static void __init do_boot_cpu(__u8 cpu)
             & ~(voyager_extended_vic_processors
                 & voyager_allowed_boot_processors);
 
-        /* This is an area in head.S which was used to set up the
-         * initial kernel stack.  We need to alter this to give the
-         * booting CPU a new stack (taken from its idle process) */
-        extern struct {
-                __u8 *sp;
-                unsigned short ss;
-        } stack_start;
         /* This is the format of the CPI IDT gate (in real mode) which
          * we're hijacking to boot the CPU */
         union IDTFormat {
diff --git a/include/asm-x86/smp.h b/include/asm-x86/smp.h
index d02e6eacee39..78ef16dd194b 100644
--- a/include/asm-x86/smp.h
+++ b/include/asm-x86/smp.h
@@ -28,6 +28,13 @@ extern const unsigned char trampoline_data [];
 extern const unsigned char trampoline_end  [];
 extern unsigned char *trampoline_base;
 
+/* Static state in head.S used to set up a CPU */
+extern struct {
+        void *sp;
+        unsigned short ss;
+} stack_start;
+
+
 struct smp_ops {
         void (*smp_prepare_boot_cpu)(void);
         void (*smp_prepare_cpus)(unsigned max_cpus);