Re: [Qemu-devel] [PATCH] multiboot: Prevent loading of x86_64 images

[Avi Kivity]

 On 08/19/2010 02:24 PM, Adam Lackorzynski wrote:
> A via -kernel supplied x86_64 ELF image is being started in 32bit mode.
> Detect and exit if a 64bit image has been supplied.
>
>
>
> diff --git a/hw/multiboot.c b/hw/multiboot.c
> index dc980e6..e9dcbc9 100644
> --- a/hw/multiboot.c
> +++ b/hw/multiboot.c
> @@ -171,6 +171,12 @@ int load_multiboot(void *fw_cfg,
>           uint64_t elf_low, elf_high;
>           int kernel_size;
>           fclose(f);
> +
> +        if (((struct elf64_hdr*)header)->e_machine == EM_X86_64) {
> +            fprintf(stderr, "Cannot load x86-64 image, give a 32bit one.\n");
> +            exit(1);
> +        }
> +
>           kernel_size = load_elf(kernel_filename, NULL, NULL,&elf_entry,
>                                  &elf_low,&elf_high, 0, ELF_MACHINE, 0);
>           if (kernel_size<  0) {

We rely on the existing behaviour in kvm-unit-tests.git.  Tests (.flat 
files) are 64-bit elf binaries that are loaded in 32-bit more and switch 
immediately to 64-bit.

We can easily wrap them in a 32-bit elf, but that's a needless complication.

--
error compiling committee.c: too many arguments to function