Use the new kallsyms APIs that matches symbols name with .XXX
suffix. This allows userspace tools to get kprobes on the expected
function name, while the actual symbol has a .llvm.<hash> suffix.
This only effects kernel compile with CONFIG_LTO_CLANG.
Signed-off-by: Song Liu <song@xxxxxxxxxx>
---
kernel/kprobes.c | 6 +++++-
kernel/trace/trace_kprobe.c | 11 ++++++++++-
2 files changed, 15 insertions(+), 2 deletions(-)
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index e85de37d9e1e..99102283b076 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -70,7 +70,11 @@ static DEFINE_PER_CPU(struct kprobe *, kprobe_instance);
kprobe_opcode_t * __weak kprobe_lookup_name(const char *name,
unsigned int __unused)
{
- return ((kprobe_opcode_t *)(kallsyms_lookup_name(name)));
+ unsigned long addr = kallsyms_lookup_name(name);
+
+ if (IS_ENABLED(CONFIG_LTO_CLANG) && !addr)
+ addr = kallsyms_lookup_name_without_suffix(name);
+ return ((kprobe_opcode_t *)(addr));
}
/*
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 61a6da808203..d2ad0c561c83 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -203,6 +203,10 @@ unsigned long trace_kprobe_address(struct trace_kprobe *tk)
if (tk->symbol) {
addr = (unsigned long)
kallsyms_lookup_name(trace_kprobe_symbol(tk));
+
+ if (IS_ENABLED(CONFIG_LTO_CLANG) && !addr)
+ addr = kallsyms_lookup_name_without_suffix(trace_kprobe_symbol(tk));
+
if (addr)
addr += tk->rp.kp.offset;
} else {
@@ -766,8 +770,13 @@ static unsigned int number_of_same_symbols(const char *mod, const char *func_nam
{
struct sym_count_ctx ctx = { .count = 0, .name = func_name };
- if (!mod)
+ if (!mod) {
kallsyms_on_each_match_symbol(count_symbols, func_name, &ctx.count);
+ if (IS_ENABLED(CONFIG_LTO_CLANG) && !ctx.count) {
+ kallsyms_on_each_match_symbol_without_suffix(
+ count_symbols, func_name, &ctx.count);
+ }
+ }
module_kallsyms_on_each_symbol(mod, count_mod_symbols, &ctx);
--
2.43.0
