Re: [REGRESSION] v6.12.35: (build) kallsyms.h:21:10: fatal error: execinfo.h: No such file or directory

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

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