[PATCH v3 2/2] arm64: Unconditionally override SYM_FUNC macros

[Mark Brown]

Currently we only override the SYM_FUNC macros when we need to insert
BTI C into them.  Since we now unconditionally provide the BTI_C macro
used to do that let's always override them, that way any issues with our
overrides it'll show up more consistently.

Since this means that we now have an unconditional definition of BTI_C
update the other users to remove the ifdefs around usage, making them
look a bit neater.

Suggested-by: Mark Rutland <mark.rutland at arm.com>
Signed-off-by: Mark Brown <broonie at kernel.org>
---
 arch/arm64/include/asm/linkage.h | 16 +++++++++++-----
 arch/arm64/kernel/entry-ftrace.S |  4 ----
 arch/arm64/lib/kasan_sw_tags.S   |  2 --
 3 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/arch/arm64/include/asm/linkage.h b/arch/arm64/include/asm/linkage.h
index c5d0c11d7709..1cfa8bb33edd 100644
--- a/arch/arm64/include/asm/linkage.h
+++ b/arch/arm64/include/asm/linkage.h
@@ -8,10 +8,18 @@
 
 #define BTI_C bti c ;
 
+#else
+
+#define BTI_C
+
+#endif
+
 /*
- * When using in-kernel BTI we need to ensure that PCS-conformant assembly
- * functions have suitable annotations.  Override SYM_FUNC_START to insert
- * a BTI landing pad at the start of everything.
+ * When using in-kernel BTI we need to ensure that PCS-conformant
+ * assembly functions have suitable annotations.  Override
+ * SYM_FUNC_START to insert a BTI landing pad at the start of
+ * everything, the override is done unconditionally so we're more
+ * likely to notice any drift from the overridden definitions.
  */
 #define SYM_FUNC_START(name)				\
 	SYM_START(name, SYM_L_GLOBAL, SYM_A_ALIGN)	\
@@ -37,8 +45,6 @@
 	SYM_START(name, SYM_L_WEAK, SYM_A_NONE)		\
 	BTI_C
 
-#endif
-
 /*
  * Annotate a function as position independent, i.e., safe to be called before
  * the kernel virtual mapping is activated.
diff --git a/arch/arm64/kernel/entry-ftrace.S b/arch/arm64/kernel/entry-ftrace.S
index 8cf970d219f5..46a2de864794 100644
--- a/arch/arm64/kernel/entry-ftrace.S
+++ b/arch/arm64/kernel/entry-ftrace.S
@@ -77,17 +77,13 @@
 	.endm
 
 SYM_CODE_START(ftrace_regs_caller)
-#ifdef BTI_C
 	BTI_C
-#endif
 	ftrace_regs_entry	1
 	b	ftrace_common
 SYM_CODE_END(ftrace_regs_caller)
 
 SYM_CODE_START(ftrace_caller)
-#ifdef BTI_C
 	BTI_C
-#endif
 	ftrace_regs_entry	0
 	b	ftrace_common
 SYM_CODE_END(ftrace_caller)
diff --git a/arch/arm64/lib/kasan_sw_tags.S b/arch/arm64/lib/kasan_sw_tags.S
index 5b04464c045e..a6d6fa2f761e 100644
--- a/arch/arm64/lib/kasan_sw_tags.S
+++ b/arch/arm64/lib/kasan_sw_tags.S
@@ -38,9 +38,7 @@
  * incremented by 256 prior to return).
  */
 SYM_CODE_START(__hwasan_tag_mismatch)
-#ifdef BTI_C
 	BTI_C
-#endif
 	add	x29, sp, #232
 	stp	x2, x3, [sp, #8 * 2]
 	stp	x4, x5, [sp, #8 * 4]
-- 
2.30.2