[PATCH v8 2/3] ARM: Add warn suppress parameter to arm_gen_branch_link()

From: Alexander A Sverdlin
Date: Tue Mar 30 2021 - 07:41:23 EST


From: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxx>

Will be used in the following patch. No functional change.

Signed-off-by: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxx>
---
arch/arm/include/asm/insn.h | 8 ++++----
arch/arm/kernel/ftrace.c | 2 +-
arch/arm/kernel/insn.c | 19 ++++++++++---------
3 files changed, 15 insertions(+), 14 deletions(-)

diff --git a/arch/arm/include/asm/insn.h b/arch/arm/include/asm/insn.h
index f20e08a..5475cbf 100644
--- a/arch/arm/include/asm/insn.h
+++ b/arch/arm/include/asm/insn.h
@@ -13,18 +13,18 @@ arm_gen_nop(void)
}

unsigned long
-__arm_gen_branch(unsigned long pc, unsigned long addr, bool link);
+__arm_gen_branch(unsigned long pc, unsigned long addr, bool link, bool warn);

static inline unsigned long
arm_gen_branch(unsigned long pc, unsigned long addr)
{
- return __arm_gen_branch(pc, addr, false);
+ return __arm_gen_branch(pc, addr, false, true);
}

static inline unsigned long
-arm_gen_branch_link(unsigned long pc, unsigned long addr)
+arm_gen_branch_link(unsigned long pc, unsigned long addr, bool warn)
{
- return __arm_gen_branch(pc, addr, true);
+ return __arm_gen_branch(pc, addr, true, warn);
}

#endif
diff --git a/arch/arm/kernel/ftrace.c b/arch/arm/kernel/ftrace.c
index 9a79ef6..61de817 100644
--- a/arch/arm/kernel/ftrace.c
+++ b/arch/arm/kernel/ftrace.c
@@ -70,7 +70,7 @@ int ftrace_arch_code_modify_post_process(void)

static unsigned long ftrace_call_replace(unsigned long pc, unsigned long addr)
{
- return arm_gen_branch_link(pc, addr);
+ return arm_gen_branch_link(pc, addr, true);
}

static int ftrace_modify_code(unsigned long pc, unsigned long old,
diff --git a/arch/arm/kernel/insn.c b/arch/arm/kernel/insn.c
index 2e844b7..db0acbb 100644
--- a/arch/arm/kernel/insn.c
+++ b/arch/arm/kernel/insn.c
@@ -3,8 +3,9 @@
#include <linux/kernel.h>
#include <asm/opcodes.h>

-static unsigned long
-__arm_gen_branch_thumb2(unsigned long pc, unsigned long addr, bool link)
+static unsigned long __arm_gen_branch_thumb2(unsigned long pc,
+ unsigned long addr, bool link,
+ bool warn)
{
unsigned long s, j1, j2, i1, i2, imm10, imm11;
unsigned long first, second;
@@ -12,7 +13,7 @@ __arm_gen_branch_thumb2(unsigned long pc, unsigned long addr, bool link)

offset = (long)addr - (long)(pc + 4);
if (offset < -16777216 || offset > 16777214) {
- WARN_ON_ONCE(1);
+ WARN_ON_ONCE(warn);
return 0;
}

@@ -33,8 +34,8 @@ __arm_gen_branch_thumb2(unsigned long pc, unsigned long addr, bool link)
return __opcode_thumb32_compose(first, second);
}

-static unsigned long
-__arm_gen_branch_arm(unsigned long pc, unsigned long addr, bool link)
+static unsigned long __arm_gen_branch_arm(unsigned long pc, unsigned long addr,
+ bool link, bool warn)
{
unsigned long opcode = 0xea000000;
long offset;
@@ -44,7 +45,7 @@ __arm_gen_branch_arm(unsigned long pc, unsigned long addr, bool link)

offset = (long)addr - (long)(pc + 8);
if (unlikely(offset < -33554432 || offset > 33554428)) {
- WARN_ON_ONCE(1);
+ WARN_ON_ONCE(warn);
return 0;
}

@@ -54,10 +55,10 @@ __arm_gen_branch_arm(unsigned long pc, unsigned long addr, bool link)
}

unsigned long
-__arm_gen_branch(unsigned long pc, unsigned long addr, bool link)
+__arm_gen_branch(unsigned long pc, unsigned long addr, bool link, bool warn)
{
if (IS_ENABLED(CONFIG_THUMB2_KERNEL))
- return __arm_gen_branch_thumb2(pc, addr, link);
+ return __arm_gen_branch_thumb2(pc, addr, link, warn);
else
- return __arm_gen_branch_arm(pc, addr, link);
+ return __arm_gen_branch_arm(pc, addr, link, warn);
}
--
2.10.2