Re: [Qemu-devel] [PATCH] compile x86_64 on i386

[Anthony Liguori]

Glauber Costa wrote:
> This patch allows qemu-system-x86_64 to be compiled on a i386 host.
>   

For this to properly work, you need to fix the FIXMEs in 
target-i386/kvm.c that are around lm_capable_check.  Basically, if 
you're on a 32-bit kernel, but a 64-bit capable processor, you need to 
mask long mode from the guest or it may try to use it.

Regards,

Anthony Liguori

> ---
>  configure |   17 ++++++++++-------
>  1 files changed, 10 insertions(+), 7 deletions(-)
>
> diff --git a/configure b/configure
> index 067c3c5..65f0c74 100755
> --- a/configure
> +++ b/configure
> @@ -1447,13 +1447,16 @@ interp_prefix1=`echo "$interp_prefix" | sed 
> "s/%M/$target_cpu/g"`
>  echo "#define CONFIG_QEMU_PREFIX \"$interp_prefix1\"" >> $config_h
>  gdb_xml_files=""
>  
> -# FIXME allow i386 to build on x86_64 and vice versa
> -if test "$kvm" = "yes" -a "$target_cpu" != "$cpu" ; then
> -  kvm="no"
> -fi
> -# Disable KVM for linux-user
> -if test "$kvm" = "yes" -a "$target_softmmu" = "no" ; then
> -  kvm="no"
> +if test "$kvm" = "yes";
> +then
> +  # Disable KVM for linux-user
> +  if test "$target_softmmu" = "no";
> +  then
> +     kvm="no"
> +  elif test "$target_cpu" != "$cpu" && test ! "$cpu" = "i386" -a  "$target_cpu" = 
> "x86_64" ;
> +  then
> +        kvm="no"
> +  fi
>  fi
>  
>  case "$target_cpu" in
>