With CONFIG_VIRTIO_UML=y, GNU ld < 2.36 fails to link UML vmlinux
(w/wo CONFIG_LD_SCRIPT_STATIC).

  `.exit.text' referenced in section `.uml.exitcall.exit' of arch/um/drivers/virtio_uml.o: defined in discarded section `.exit.text' of arch/um/drivers/virtio_uml.o
  collect2: error: ld returned 1 exit status

This fix is similar to the following commits:

- 4b9880dbf3bd ("powerpc/vmlinux.lds: Define RUNTIME_DISCARD_EXIT")
- a494398bde27 ("s390: define RUNTIME_DISCARD_EXIT to fix link error
  with GNU ld < 2.36")
- c1c551bebf92 ("sh: define RUNTIME_DISCARD_EXIT")

Fixes: 99cb0d917ffa ("arch: fix broken BuildID for arm64 and riscv")
Reported-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---

 arch/um/kernel/vmlinux.lds.S | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/um/kernel/vmlinux.lds.S b/arch/um/kernel/vmlinux.lds.S
index 16e49bfa2b42..53d719c04ba9 100644
--- a/arch/um/kernel/vmlinux.lds.S
+++ b/arch/um/kernel/vmlinux.lds.S
@@ -1,4 +1,4 @@
-
+#define RUNTIME_DISCARD_EXIT
 KERNEL_STACK_SIZE = 4096 * (1 << CONFIG_KERNEL_STACK_ORDER);
 
 #ifdef CONFIG_LD_SCRIPT_STATIC
-- 
2.34.1

Hi Masahiro,

On Wed, 8 Feb 2023 01:41:56 +0900 Masahiro Yamada <masahiroy@kernel.org> wrote:

> With CONFIG_VIRTIO_UML=y, GNU ld < 2.36 fails to link UML vmlinux
> (w/wo CONFIG_LD_SCRIPT_STATIC).
> 
>   `.exit.text' referenced in section `.uml.exitcall.exit' of arch/um/drivers/virtio_uml.o: defined in discarded section `.exit.text' of arch/um/drivers/virtio_uml.o
>   collect2: error: ld returned 1 exit status
> 
> This fix is similar to the following commits:
> 
> - 4b9880dbf3bd ("powerpc/vmlinux.lds: Define RUNTIME_DISCARD_EXIT")
> - a494398bde27 ("s390: define RUNTIME_DISCARD_EXIT to fix link error
>   with GNU ld < 2.36")
> - c1c551bebf92 ("sh: define RUNTIME_DISCARD_EXIT")
> 
> Fixes: 99cb0d917ffa ("arch: fix broken BuildID for arm64 and riscv")
> Reported-by: SeongJae Park <sj@kernel.org>
> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Tested-by: SeongJae Park <sj@kernel.org>


Thanks.
SJ

> ---
> 
>  arch/um/kernel/vmlinux.lds.S | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/um/kernel/vmlinux.lds.S b/arch/um/kernel/vmlinux.lds.S
> index 16e49bfa2b42..53d719c04ba9 100644
> --- a/arch/um/kernel/vmlinux.lds.S
> +++ b/arch/um/kernel/vmlinux.lds.S
> @@ -1,4 +1,4 @@
> -
> +#define RUNTIME_DISCARD_EXIT
>  KERNEL_STACK_SIZE = 4096 * (1 << CONFIG_KERNEL_STACK_ORDER);
>  
>  #ifdef CONFIG_LD_SCRIPT_STATIC
> -- 
> 2.34.1
>