The level4_kernel_pgt is only defined when X86_5LEVEL is enabled.
So declare check_la57_support() as inline to make sure the code
referring to level4_kernel_pgt is optimized out. This is a preparation
for CONFIG_CC_OPTIMIZE_FOR_DEBUGGING.

Signed-off-by: Changbin Du <redacted>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Masahiro Yamada <redacted>
---
 arch/x86/kernel/head64.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index 5dc377dc9d7b..5ae682f2aa83 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c

@@ -98,7 +98,7 @@ static bool __head check_la57_support(unsigned long physaddr)
 	return true;
 }
 #else
-static bool __head check_la57_support(unsigned long physaddr)
+static inline bool __head check_la57_support(unsigned long physaddr)
 {
 	return false;
 }

-- 
2.17.1