From e332938e6fc8117fb9bb1374339cea879b3972d9 Mon Sep 17 00:00:00 2001
From: "GONG, Ruiqi" <gongruiqi1@huawei.com>
Date: Sun, 20 Aug 2023 19:15:09 +0800
Subject: [PATCH] samples: ftrace: Replace bti assembly with hint for older
 compiler

When cross-building the arm64 kernel with allmodconfig using GCC 9.4,
the following error occurs on multiple files under samples/ftrace/:

/tmp/ccPC1ODs.s: Assembler messages:
/tmp/ccPC1ODs.s:8: Error: selected processor does not support `bti c'

Fix this issue by replacing `bti c` with `hint 34`, which is compatible
for the older compiler.

Link: https://lore.kernel.org/linux-trace-kernel/20230820111509.1470826-1-gongruiqi@huaweicloud.com

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Florent Revest <revest@chromium.org>
Fixes: 8c3526fb86060cb5 ("arm64: ftrace: Add direct call trampoline samples support")
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: GONG, Ruiqi <gongruiqi1@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
---
 samples/ftrace/ftrace-direct-modify.c       | 4 ++--
 samples/ftrace/ftrace-direct-multi-modify.c | 4 ++--
 samples/ftrace/ftrace-direct-multi.c        | 2 +-
 samples/ftrace/ftrace-direct-too.c          | 2 +-
 samples/ftrace/ftrace-direct.c              | 2 +-
 5 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/samples/ftrace/ftrace-direct-modify.c b/samples/ftrace/ftrace-direct-modify.c
index e5ed08098ff31..e2a6a69352dfb 100644
--- a/samples/ftrace/ftrace-direct-modify.c
+++ b/samples/ftrace/ftrace-direct-modify.c
@@ -105,7 +105,7 @@ asm (
 "	.type		my_tramp1, @function\n"
 "	.globl		my_tramp1\n"
 "   my_tramp1:"
-"	bti	c\n"
+"	hint	34\n" // bti	c
 "	sub	sp, sp, #16\n"
 "	stp	x9, x30, [sp]\n"
 "	bl	my_direct_func1\n"
@@ -117,7 +117,7 @@ asm (
 "	.type		my_tramp2, @function\n"
 "	.globl		my_tramp2\n"
 "   my_tramp2:"
-"	bti	c\n"
+"	hint	34\n" // bti	c
 "	sub	sp, sp, #16\n"
 "	stp	x9, x30, [sp]\n"
 "	bl	my_direct_func2\n"
diff --git a/samples/ftrace/ftrace-direct-multi-modify.c b/samples/ftrace/ftrace-direct-multi-modify.c
index 292cff2b3f5d7..2e349834d63c3 100644
--- a/samples/ftrace/ftrace-direct-multi-modify.c
+++ b/samples/ftrace/ftrace-direct-multi-modify.c
@@ -112,7 +112,7 @@ asm (
 "	.type		my_tramp1, @function\n"
 "	.globl		my_tramp1\n"
 "   my_tramp1:"
-"	bti	c\n"
+"	hint	34\n" // bti	c
 "	sub	sp, sp, #32\n"
 "	stp	x9, x30, [sp]\n"
 "	str	x0, [sp, #16]\n"
@@ -127,7 +127,7 @@ asm (
 "	.type		my_tramp2, @function\n"
 "	.globl		my_tramp2\n"
 "   my_tramp2:"
-"	bti	c\n"
+"	hint	34\n" // bti	c
 "	sub	sp, sp, #32\n"
 "	stp	x9, x30, [sp]\n"
 "	str	x0, [sp, #16]\n"
diff --git a/samples/ftrace/ftrace-direct-multi.c b/samples/ftrace/ftrace-direct-multi.c
index b4391e08c913e..9243dbfe4d0c1 100644
--- a/samples/ftrace/ftrace-direct-multi.c
+++ b/samples/ftrace/ftrace-direct-multi.c
@@ -75,7 +75,7 @@ asm (
 "	.type		my_tramp, @function\n"
 "	.globl		my_tramp\n"
 "   my_tramp:"
-"	bti	c\n"
+"	hint	34\n" // bti	c
 "	sub	sp, sp, #32\n"
 "	stp	x9, x30, [sp]\n"
 "	str	x0, [sp, #16]\n"
diff --git a/samples/ftrace/ftrace-direct-too.c b/samples/ftrace/ftrace-direct-too.c
index e9804c5307c0c..e39c3563ae4e4 100644
--- a/samples/ftrace/ftrace-direct-too.c
+++ b/samples/ftrace/ftrace-direct-too.c
@@ -81,7 +81,7 @@ asm (
 "	.type		my_tramp, @function\n"
 "	.globl		my_tramp\n"
 "   my_tramp:"
-"	bti	c\n"
+"	hint	34\n" // bti	c
 "	sub	sp, sp, #48\n"
 "	stp	x9, x30, [sp]\n"
 "	stp	x0, x1, [sp, #16]\n"
diff --git a/samples/ftrace/ftrace-direct.c b/samples/ftrace/ftrace-direct.c
index 20f4a7caa810e..32c477da1e9aa 100644
--- a/samples/ftrace/ftrace-direct.c
+++ b/samples/ftrace/ftrace-direct.c
@@ -72,7 +72,7 @@ asm (
 "	.type		my_tramp, @function\n"
 "	.globl		my_tramp\n"
 "   my_tramp:"
-"	bti	c\n"
+"	hint	34\n" // bti	c
 "	sub	sp, sp, #32\n"
 "	stp	x9, x30, [sp]\n"
 "	str	x0, [sp, #16]\n"
-- 
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