Re: [PATCH v2 1/4] exec: Allow loading x86_64 executables on x86_64

[Samuel Thibault]

Applied, thanks!

Sergey Bugaev, le lun. 15 mai 2023 10:35:57 +0300, a ecrit:
> Since we don't support mixing i386 and x86_64 binaries on the same
> system (as running them requires different build-time gnumach
> configurations), the exec server can simply require the binary being
> loaded to have been built for the same architecture as the exec server
> itself.
> ---
>  exec/exec.c     | 8 +++++++-
>  exec/hostarch.c | 9 +++++++++
>  2 files changed, 16 insertions(+), 1 deletion(-)
> 
> diff --git a/exec/exec.c b/exec/exec.c
> index 8944167d..2e5fbfcd 100644
> --- a/exec/exec.c
> +++ b/exec/exec.c
> @@ -518,6 +518,12 @@ prepare (file_t file, struct execdata *e)
>  #define host_ELFDATA ELFDATA2LSB
>  #endif
>  
> +#ifdef __LP64__
> +#define host_ELFCLASS ELFCLASS64
> +#else
> +#define host_ELFCLASS ELFCLASS32
> +#endif
> +
>  static void
>  check_elf (struct execdata *e)
>  {
> @@ -539,7 +545,7 @@ check_elf (struct execdata *e)
>        return;
>      }
>  
> -  if (ehdr->e_ident[EI_CLASS] != ELFCLASS32 ||
> +  if (ehdr->e_ident[EI_CLASS] != host_ELFCLASS ||
>        ehdr->e_ident[EI_DATA] != host_ELFDATA ||
>        ehdr->e_ident[EI_VERSION] != EV_CURRENT ||
>        ehdr->e_version != EV_CURRENT ||
> diff --git a/exec/hostarch.c b/exec/hostarch.c
> index 363fda69..ed50e0a8 100644
> --- a/exec/hostarch.c
> +++ b/exec/hostarch.c
> @@ -72,6 +72,15 @@ elf_machine_matches_host (ElfW(Half) e_machine)
>      case CPU_TYPE_PENTIUMPRO:
>        CACHE (e_machine == EM_386);
>  
> +    /* When building for x86_64, CPU_TYPE_X86_64 must be defined; otherwise
> +       it's OK if we don't compile this branch -- none of the branches other
> +       than the actual architecture the code is built for are going to be
> +       taken anyway.  */
> +#if defined (CPU_TYPE_X86_64) || defined (__x86_64__)
> +    case CPU_TYPE_X86_64:
> +      CACHE (e_machine == EM_X86_64);
> +#endif
> +
>      case CPU_TYPE_POWERPC:
>        CACHE (e_machine == EM_PPC);
>  
> -- 
> 2.40.1
> 
> 

-- 
Samuel
---
Pour une évaluation indépendante, transparente et rigoureuse !
Je soutiens la Commission d'Évaluation de l'Inria.