Stephen reported following linker warnings on powerpc build: ld: warning: orphan section `.BTF_ids' from `kernel/trace/bpf_trace.o' being placed in section `.BTF_ids' ld: warning: orphan section `.BTF_ids' from `kernel/bpf/btf.o' being placed in section `.BTF_ids' ld: warning: orphan section `.BTF_ids' from `kernel/bpf/stackmap.o' being placed in section `.BTF_ids' ld: warning: orphan section `.BTF_ids' from `net/core/filter.o' being placed in section `.BTF_ids' ld: warning: orphan section `.BTF_ids' from `kernel/trace/bpf_trace.o' being placed in section `.BTF_ids'
It's because we generated .BTF_ids section even when CONFIG_DEBUG_INFO_BTF is not enabled. Fixing this by generating empty btf_id arrays for this case. Reported-by: Stephen Rothwell <s...@canb.auug.org.au> Tested-by: Geert Uytterhoeven <geert+rene...@glider.be> Signed-off-by: Jiri Olsa <jo...@kernel.org> --- include/linux/btf_ids.h | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/include/linux/btf_ids.h b/include/linux/btf_ids.h index fe019774f8a7..b3c73db9587c 100644 --- a/include/linux/btf_ids.h +++ b/include/linux/btf_ids.h @@ -3,6 +3,8 @@ #ifndef _LINUX_BTF_IDS_H #define _LINUX_BTF_IDS_H +#ifdef CONFIG_DEBUG_INFO_BTF + #include <linux/compiler.h> /* for __PASTE */ /* @@ -83,5 +85,12 @@ asm( \ ".zero 4 \n" \ ".popsection; \n"); +#else + +#define BTF_ID_LIST(name) static u32 name[5]; +#define BTF_ID(prefix, name) +#define BTF_ID_UNUSED + +#endif /* CONFIG_DEBUG_INFO_BTF */ #endif -- 2.25.4
