2 files changed, 24 insertions, 0 deletions

diff --git a/arch/x86/kernel/signal_32.c b/arch/x86/kernel/signal_32.c
index 0ff8d8750a7d..d9909881ac66 100644
--- a/arch/x86/kernel/signal_32.c
+++ b/arch/x86/kernel/signal_32.c
@@ -125,6 +125,7 @@ sys_sigaction(int sig, const struct old_sigaction __user *act,
         return ret;
 }
 
+#ifdef CONFIG_X86_32
 asmlinkage int sys_sigaltstack(unsigned long bx)
 {
         /*
@@ -137,6 +138,14 @@ asmlinkage int sys_sigaltstack(unsigned long bx)
 
         return do_sigaltstack(uss, uoss, regs->sp);
 }
+#else /* !CONFIG_X86_32 */
+asmlinkage long
+sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
+                struct pt_regs *regs)
+{
+        return do_sigaltstack(uss, uoss, regs->sp);
+}
+#endif /* CONFIG_X86_32 */
 
 #define COPY(x)                 {               \
         err |= __get_user(regs->x, &sc->x);     \
diff --git a/arch/x86/kernel/signal_64.c b/arch/x86/kernel/signal_64.c
index c52244ac19fc..b6e4fe03a36b 100644
--- a/arch/x86/kernel/signal_64.c
+++ b/arch/x86/kernel/signal_64.c
@@ -50,12 +50,27 @@
 # define FIX_EFLAGS     __FIX_EFLAGS
 #endif
 
+#ifdef CONFIG_X86_32
+asmlinkage int sys_sigaltstack(unsigned long bx)
+{
+        /*
+         * This is needed to make gcc realize it doesn't own the
+         * "struct pt_regs"
+         */
+        struct pt_regs *regs = (struct pt_regs *)&bx;
+        const stack_t __user *uss = (const stack_t __user *)bx;
+        stack_t __user *uoss = (stack_t __user *)regs->cx;
+
+        return do_sigaltstack(uss, uoss, regs->sp);
+}
+#else /* !CONFIG_X86_32 */
 asmlinkage long
 sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
                 struct pt_regs *regs)
 {
         return do_sigaltstack(uss, uoss, regs->sp);
 }
+#endif /* CONFIG_X86_32 */
 
 #define COPY(x)                 {               \
         err |= __get_user(regs->x, &sc->x);     \