6.5-stable review patch. If anyone has any objections, please let me know.
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From: Nick Desaulniers ndesaulniers@google.com
commit c0bb9fb0e52a64601d38b3739b729d9138d4c8a1 upstream.
Marcus and Satya reported an issue where BTF_ID macro generates same symbol in separate objects and that breaks final vmlinux link.
ld.lld: error: ld-temp.o <inline asm>:14577:1: symbol '__BTF_ID__struct__cgroup__624' is already defined
This can be triggered under specific configs when __COUNTER__ happens to be the same for the same symbol in two different translation units, which is already quite unlikely to happen.
Add __LINE__ number suffix to make BTF_ID symbol more unique, which is not a complete fix, but it would help for now and meanwhile we can work on better solution as suggested by Andrii.
Cc: stable@vger.kernel.org Reported-by: Satya Durga Srinivasu Prabhala quic_satyap@quicinc.com Reported-by: Marcus Seyfarth m.seyfarth@gmail.com Closes: https://github.com/ClangBuiltLinux/linux/issues/1913 Debugged-by: Nathan Chancellor nathan@kernel.org Co-developed-by: Jiri Olsa jolsa@kernel.org Link: https://lore.kernel.org/bpf/CAEf4Bzb5KQ2_LmhN769ifMeSJaWfebccUasQOfQKaOd0nQ5... Signed-off-by: Nick Desaulniers ndesaulniers@google.com Link: https://lore.kernel.org/r/20230915-bpf_collision-v3-2-263fc519c21f@google.co... Signed-off-by: Alexei Starovoitov ast@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- tools/include/linux/btf_ids.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/tools/include/linux/btf_ids.h +++ b/tools/include/linux/btf_ids.h @@ -38,7 +38,7 @@ asm( \ ____BTF_ID(symbol)
#define __ID(prefix) \ - __PASTE(prefix, __COUNTER__) + __PASTE(__PASTE(prefix, __COUNTER__), __LINE__)
/* * The BTF_ID defines unique symbol for each ID pointing