On Tue, Jul 01, 2025 at 02:10:26PM +0200, Natanael Copa wrote:

Hi!

I bumped into a build regression when building Alpine Linux kernel 6.12.35 on x86_64:

In file included from ../arch/x86/tools/insn_decoder_test.c:13: ../tools/include/linux/kallsyms.h:21:10: fatal error: execinfo.h: No such file or directory 21 | #include <execinfo.h> | ^~~~~~~~~~~~ compilation terminated.

The 6.12.34 kernel built just fine.

I bisected it to:

commit b8abcba6e4aec53868dfe44f97270fc4dee0df2a (HEAD) Author: Sergio Gonz_lez Collado sergio.collado@gmail.com Date: Sun Mar 2 23:15:18 2025 +0100

Kunit to check the longest symbol length

commit c104c16073b7fdb3e4eae18f66f4009f6b073d6f upstream. which has this hunk:

diff --git a/arch/x86/tools/insn_decoder_test.c b/arch/x86/tools/insn_decoder_test.c index 472540aeabc2..6c2986d2ad11 100644 --- a/arch/x86/tools/insn_decoder_test.c +++ b/arch/x86/tools/insn_decoder_test.c @@ -10,6 +10,7 @@ #include <assert.h> #include <unistd.h> #include <stdarg.h> +#include <linux/kallsyms.h> #define unlikely(cond) (cond) @@ -106,7 +107,7 @@ static void parse_args(int argc, char **argv) } } -#define BUFSIZE 256 +#define BUFSIZE (256 + KSYM_NAME_LEN) int main(int argc, char **argv) {

It looks like the linux/kallsyms.h was included to get KSYM_NAME_LEN. Unfortunately it also introduced the include of execinfo.h, which does not exist on musl libc.

This has previously been reported to and tried fixed: https://lore.kernel.org/stable/DB0OSTC6N4TL.2NK75K2CWE9JV@pwned.life/T/#t

Would it be an idea to revert commit b8abcba6e4ae til we have a proper solution for this?

Please get the fix in Linus's tree first and then we can backport it as needed.

thanks,

greg k-h