x86/cpu: Export native_write_cr4() only when CONFIG_LKTDM=m

Modules have no business poking into this but fixing this is for later.

 [ bp: Carve out from an earlier patch. ]

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200421092558.939985695@linutronix.de

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 82042f40fc45a722379813544b0784df05746a22..eab3ebd22927e0518e4317538d57ced15387aedd 100644 (file)
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -387,7 +387,9 @@ set_register:
                          bits_missing);
        }
 }
+#if IS_MODULE(CONFIG_LKDTM)
 EXPORT_SYMBOL_GPL(native_write_cr4);
+#endif
 
 void cr4_update_irqsoff(unsigned long set, unsigned long clear)
 {