1 files changed, 8 insertions, 0 deletions

diff --git a/arch/x86/include/asm/smpboot_hooks.h b/arch/x86/include/asm/smpboot_hooks.h
index 725b77831993..49adfd7bb4a4 100644
--- a/arch/x86/include/asm/smpboot_hooks.h
+++ b/arch/x86/include/asm/smpboot_hooks.h
@@ -10,7 +10,11 @@ static inline void smpboot_clear_io_apic_irqs(void)
 
 static inline void smpboot_setup_warm_reset_vector(unsigned long start_eip)
 {
+        unsigned long flags;
+
+        spin_lock_irqsave(&rtc_lock, flags);
         CMOS_WRITE(0xa, 0xf);
+        spin_unlock_irqrestore(&rtc_lock, flags);
         local_flush_tlb();
         pr_debug("1.\n");
         *((volatile unsigned short *)phys_to_virt(apic->trampoline_phys_high)) =
@@ -23,6 +27,8 @@ static inline void smpboot_setup_warm_reset_vector(unsigned long start_eip)
 
 static inline void smpboot_restore_warm_reset_vector(void)
 {
+        unsigned long flags;
+
         /*
          * Install writable page 0 entry to set BIOS data area.
          */
@@ -32,7 +38,9 @@ static inline void smpboot_restore_warm_reset_vector(void)
          * Paranoid:  Set warm reset code and vector here back
          * to default values.
          */
+        spin_lock_irqsave(&rtc_lock, flags);
         CMOS_WRITE(0, 0xf);
+        spin_unlock_irqrestore(&rtc_lock, flags);
 
         *((volatile u32 *)phys_to_virt(apic->trampoline_phys_low)) = 0;
 }