With CONFIG_LTO_CLANG, the compiler/linker adds .llvm.<hash> suffix to local symbols to avoid duplications. Existing scripts/kallsyms sorts symbols without .llvm.<hash> suffix. However, this causes quite some issues later on. Some users of kallsyms, such as livepatch, have to match symbols exactly; while other users, such as kprobe, would match symbols without the suffix. Address this by sorting full symbols at build time, and split kallsyms APIs to explicitly match full symbols or without suffix. Specifically, exiting APIs will match symbols exactly. Two new APIs are added to match symbols with suffix. Use the new APIs in tracing/kprobes. Changes v1 => v2: 1. Update the APIs to remove all .XXX suffixes (v1 only removes .llvm.*). 2. Rename the APIs as *_without_suffix. (Masami Hiramatsu) 3. Fix another user from kprobe. (Masami Hiramatsu) 4. Add tests for the new APIs in kallsyms_selftests. v1: https://lore.kernel.org/live-patching/20240730005433.3559731-1-song@xxxxxxxxxx/T/#u Song Liu (3): kallsyms: Do not cleanup .llvm.<hash> suffix before sorting symbols kallsyms: Add APIs to match symbol without .XXXX suffix. tracing/kprobes: Use APIs that matches symbols without .XXX suffix include/linux/kallsyms.h | 14 ++++++ kernel/kallsyms.c | 88 +++++++++++++++++++++++++------------ kernel/kallsyms_selftest.c | 75 ++++++++++++++++++++++--------- kernel/kprobes.c | 6 ++- kernel/trace/trace_kprobe.c | 11 ++++- scripts/kallsyms.c | 31 +------------ scripts/link-vmlinux.sh | 4 -- 7 files changed, 145 insertions(+), 84 deletions(-) -- 2.43.0
