x86/asm/entry/64: Move stub_x32_execvecloser() to stub_execveat()

This is a preparatory patch for moving stub32_execve[at]() to this
file. It makes sense to have all execve stubs in one place, so
that they can reuse code.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1428439424-7258-2-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/kernel/entry_64.S

@@ -521,6 +521,23 @@ ENTRY(stub_execveat)
 	CFI_ENDPROC
 END(stub_execveat)
 
+#ifdef CONFIG_X86_X32_ABI
+ENTRY(stub_x32_execve)
+	CFI_STARTPROC
+	DEFAULT_FRAME 0, 8
+	call	compat_sys_execve
+	jmp	return_from_execve
+	CFI_ENDPROC
+END(stub_x32_execve)
+ENTRY(stub_x32_execveat)
+	CFI_STARTPROC
+	DEFAULT_FRAME 0, 8
+	call	compat_sys_execveat
+	jmp	return_from_execve
+	CFI_ENDPROC
+END(stub_x32_execveat)
+#endif
+
 /*
  * sigreturn is special because it needs to restore all registers on return.
  * This cannot be done with SYSRET, so use the IRET return path instead.
@@ -555,23 +572,6 @@ ENTRY(stub_x32_rt_sigreturn)
 	jmp  return_from_stub
 	CFI_ENDPROC
 END(stub_x32_rt_sigreturn)
-
-ENTRY(stub_x32_execve)
-	CFI_STARTPROC
-	DEFAULT_FRAME 0, 8
-	call	compat_sys_execve
-	jmp	return_from_execve
-	CFI_ENDPROC
-END(stub_x32_execve)
-
-ENTRY(stub_x32_execveat)
-	CFI_STARTPROC
-	DEFAULT_FRAME 0, 8
-	call	compat_sys_execveat
-	jmp	return_from_execve
-	CFI_ENDPROC
-END(stub_x32_execveat)
-
 #endif
 
 /*