x86,objtool: Move the ASM_REACHABLE annotation to objtool.h

Because we need a variant for .S files too.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/Yi9gOW9f1GGwwUD6@hirez.programming.kicks-ass.net

arch/x86/include/asm/bug.h

@@ -4,6 +4,7 @@
 
 #include <linux/stringify.h>
 #include <linux/instrumentation.h>
+#include <linux/objtool.h>
 
 /*
  * Despite that some emulators terminate on UD2, we use it for WARN().

arch/x86/include/asm/irq_stack.h

@@ -3,6 +3,7 @@
 #define _ASM_X86_IRQ_STACK_H
 
 #include <linux/ptrace.h>
+#include <linux/objtool.h>
 
 #include <asm/processor.h>
 

include/linux/compiler.h

@@ -125,18 +125,11 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val,
 })
 #define annotate_unreachable() __annotate_unreachable(__COUNTER__)
 
-#define ASM_REACHABLE							\
-	"998:\n\t"							\
-	".pushsection .discard.reachable\n\t"				\
-	".long 998b - .\n\t"						\
-	".popsection\n\t"
-
 /* Annotate a C jump table to allow objtool to follow the code flow */
 #define __annotate_jump_table __section(".rodata..c_jump_table")
 
 #else
 #define annotate_unreachable()
-# define ASM_REACHABLE
 #define __annotate_jump_table
 #endif
 

include/linux/objtool.h

@@ -83,6 +83,12 @@ struct unwind_hint {
 	_ASM_PTR " 986b\n\t"					\
 	".popsection\n\t"
 
+#define ASM_REACHABLE							\
+	"998:\n\t"							\
+	".pushsection .discard.reachable\n\t"				\
+	".long 998b - .\n\t"						\
+	".popsection\n\t"
+
 #else /* __ASSEMBLY__ */
 
 /*
@@ -142,6 +148,13 @@ struct unwind_hint {
 	.popsection
 .endm
 
+.macro REACHABLE
+.Lhere_\@:
+	.pushsection .discard.reachable
+	.long	.Lhere_\@ - .
+	.popsection
+.endm
+
 #endif /* __ASSEMBLY__ */
 
 #else /* !CONFIG_STACK_VALIDATION */
@@ -153,6 +166,7 @@ struct unwind_hint {
 #define STACK_FRAME_NON_STANDARD(func)
 #define STACK_FRAME_NON_STANDARD_FP(func)
 #define ANNOTATE_NOENDBR
+#define ASM_REACHABLE
 #else
 #define ANNOTATE_INTRA_FUNCTION_CALL
 .macro UNWIND_HINT sp_reg:req sp_offset=0 type:req end=0
@@ -161,6 +175,8 @@ struct unwind_hint {
 .endm
 .macro ANNOTATE_NOENDBR
 .endm
+.macro REACHABLE
+.endm
 #endif
 
 #endif /* CONFIG_STACK_VALIDATION */

tools/include/linux/objtool.h

@@ -83,6 +83,12 @@ struct unwind_hint {
 	_ASM_PTR " 986b\n\t"					\
 	".popsection\n\t"
 
+#define ASM_REACHABLE							\
+	"998:\n\t"							\
+	".pushsection .discard.reachable\n\t"				\
+	".long 998b - .\n\t"						\
+	".popsection\n\t"
+
 #else /* __ASSEMBLY__ */
 
 /*
@@ -142,6 +148,13 @@ struct unwind_hint {
 	.popsection
 .endm
 
+.macro REACHABLE
+.Lhere_\@:
+	.pushsection .discard.reachable
+	.long	.Lhere_\@ - .
+	.popsection
+.endm
+
 #endif /* __ASSEMBLY__ */
 
 #else /* !CONFIG_STACK_VALIDATION */
@@ -153,6 +166,7 @@ struct unwind_hint {
 #define STACK_FRAME_NON_STANDARD(func)
 #define STACK_FRAME_NON_STANDARD_FP(func)
 #define ANNOTATE_NOENDBR
+#define ASM_REACHABLE
 #else
 #define ANNOTATE_INTRA_FUNCTION_CALL
 .macro UNWIND_HINT sp_reg:req sp_offset=0 type:req end=0
@@ -161,6 +175,8 @@ struct unwind_hint {
 .endm
 .macro ANNOTATE_NOENDBR
 .endm
+.macro REACHABLE
+.endm
 #endif
 
 #endif /* CONFIG_STACK_VALIDATION */