x86/entry/vsyscall: Fix undefined symbol warning

Commit:

  3dc33bd30f3e1 ("x86/entry/vsyscall: Add CONFIG to control default")

did the ifdef/elif thing but GCC doesn't like that:

  arch/x86/entry/vsyscall/vsyscall_64.c:44:7: warning: "CONFIG_LEGACY_VSYSCALL_NONE" is not defined [-Wundef]
   #elif CONFIG_LEGACY_VSYSCALL_NONE
         ^

Use defined() instead.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20150921074829.GA3550@pd.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/entry/vsyscall/vsyscall_64.c b/arch/x86/entry/vsyscall/vsyscall_64.c
index 76e0fd3ea1fbe94ffd567140b850e4c4b30ac959..174c2549939d6d184b3c0e01e9d08e23356dacbe 100644 (file)
--- a/arch/x86/entry/vsyscall/vsyscall_64.c
+++ b/arch/x86/entry/vsyscall/vsyscall_64.c
@@ -39,9 +39,9 @@
 #include "vsyscall_trace.h"
 
 static enum { EMULATE, NATIVE, NONE } vsyscall_mode =
-#ifdef CONFIG_LEGACY_VSYSCALL_NATIVE
+#if defined(CONFIG_LEGACY_VSYSCALL_NATIVE)
        NATIVE;
-#elif CONFIG_LEGACY_VSYSCALL_NONE
+#elif defined(CONFIG_LEGACY_VSYSCALL_NONE)
        NONE;
 #else
        EMULATE;