From 687644209a6e95576ea453977b26dbd6248cadda Mon Sep 17 00:00:00 2001
From: Will Deacon <will.deacon@arm.com>
Date: Mon, 12 Jun 2017 14:43:25 +0100
Subject: [PATCH] arm64: ftrace: fix building without CONFIG_MODULES
When CONFIG_MODULES is disabled, we cannot dereference a module pointer:
arch/arm64/kernel/ftrace.c: In function 'ftrace_make_call':
arch/arm64/kernel/ftrace.c:107:36: error: dereferencing pointer to incomplete type 'struct module'
trampoline = (unsigned long *)mod->arch.ftrace_trampoline;
Also, the within_module() function is not defined:
arch/arm64/kernel/ftrace.c: In function 'ftrace_make_nop':
arch/arm64/kernel/ftrace.c:171:8: error: implicit declaration of function 'within_module'; did you mean 'init_module'? [-Werror=implicit-function-declaration]
This addresses both by adding replacing the IS_ENABLED(CONFIG_ARM64_MODULE_PLTS)
checks with #ifdef versions.
Fixes: e71a4e1bebaf ("arm64: ftrace: add support for far branches to dynamic ftrace")
Reported-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
---
arch/arm64/kernel/ftrace.c | 16 ++++++++++------
1 file changed, 10 insertions(+), 6 deletions(-)
diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c
index 8a42be0693c99..401aa27808a47 100644
--- a/arch/arm64/kernel/ftrace.c
+++ b/arch/arm64/kernel/ftrace.c
@@ -71,11 +71,12 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
{
unsigned long pc = rec->ip;
- long offset = (long)pc - (long)addr;
u32 old, new;
- if (IS_ENABLED(CONFIG_ARM64_MODULE_PLTS) &&
- (offset < -SZ_128M || offset >= SZ_128M)) {
+#ifdef CONFIG_ARM64_MODULE_PLTS
+ long offset = (long)pc - (long)addr;
+
+ if (offset < -SZ_128M || offset >= SZ_128M) {
unsigned long *trampoline;
struct module *mod;
@@ -121,6 +122,7 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
}
addr = (unsigned long)&trampoline[1];
}
+#endif /* CONFIG_ARM64_MODULE_PLTS */
old = aarch64_insn_gen_nop();
new = aarch64_insn_gen_branch_imm(pc, addr, AARCH64_INSN_BRANCH_LINK);
@@ -135,12 +137,13 @@ int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec,
unsigned long addr)
{
unsigned long pc = rec->ip;
- long offset = (long)pc - (long)addr;
bool validate = true;
u32 old = 0, new;
- if (IS_ENABLED(CONFIG_ARM64_MODULE_PLTS) &&
- (offset < -SZ_128M || offset >= SZ_128M)) {
+#ifdef CONFIG_ARM64_MODULE_PLTS
+ long offset = (long)pc - (long)addr;
+
+ if (offset < -SZ_128M || offset >= SZ_128M) {
u32 replaced;
/*
@@ -177,6 +180,7 @@ int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec,
old = aarch64_insn_gen_branch_imm(pc, addr,
AARCH64_INSN_BRANCH_LINK);
}
+#endif /* CONFIG_ARM64_MODULE_PLTS */
new = aarch64_insn_gen_nop();
--
2.30.2