Re: [PATCH] Use medany instead of large model for RISCV

[Jason Montleon via Grub-devel]

On Friday, March 20th, 2026 at 10:44 AM, Trevor Gamblin <tgamb...@baylibre.com> 
wrote:

> From: Jason Montleon <ja...@montleon.com>
> 
> Upstream-Status: Submitted [https://savannah.gnu.org/bugs/?65909]
> 
> Signed-off-by: Jason Montleon <ja...@montleon.com>
> Signed-off-by: Trevor Gamblin <tgamb...@baylibre.com>
> ---
> We have recently added this to the openembedded-core layer to help with RISC-V
> builds on certain platforms (e.g. the VisionFive 2). I have left the patch as 
> it
> is there, including the link to the original bug submission and the author's
> attribution. Jason, if you would like to change the attribution or anything
> about the patch, let me know and I can re-submit.

Hi Trevor,
Fedora is still using this patch and it is working for us.
https://src.fedoraproject.org/rpms/grub2/blob/rawhide/f/0283-Use-medany-instead-of-large-model-for-RISCV.patch

I did want to share that we revisited building with large model and managed to 
get it to build. This resulted in a smaller binary with far fewer relocations. 
That work is at 
http://fedora.riscv.rocks:3000/rpms/grub2/commits/branch/main-riscv64-large-code

I am not sure if one approach would be preferred over the other.

>  configure.ac | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/configure.ac b/configure.ac
> index d19fb625d..2a070c577 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -1675,7 +1675,7 @@ fi]
> 
>  CFLAGS="$TARGET_CFLAGS"
> 
> -if test "$target_cpu" = x86_64 || test "$target_cpu" = sparc64 || test 
> "$target_cpu" = riscv64 ; then
> +if test "$target_cpu" = x86_64 || test "$target_cpu" = sparc64 ; then
>    # Use large model to support 4G memory
>    AC_CACHE_CHECK([whether option -mcmodel=large works], grub_cv_cc_mcmodel, [
>      CFLAGS="$TARGET_CFLAGS -mcmodel=large"
> @@ -1685,9 +1685,11 @@ if test "$target_cpu" = x86_64 || test "$target_cpu" = 
> sparc64 || test "$target_
>    ])
>    if test "x$grub_cv_cc_mcmodel" = xyes; then
>      TARGET_CFLAGS="$TARGET_CFLAGS -mcmodel=large"
> -  elif test "$target_cpu" = sparc64 || test "$target_cpu" = riscv64; then
> +  elif test "$target_cpu" = sparc64; then
>      TARGET_CFLAGS="$TARGET_CFLAGS -mcmodel=medany"
>    fi
> +elif test "$target_cpu" = riscv64 ; then
> +    TARGET_CFLAGS="$TARGET_CFLAGS -mcmodel=medany"
>  fi
> 
>  # Stack smashing protector.
> --
> 2.53.0
> 
> 

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