Re: [PATCH v3 1/4] Align relevant sections to 4KB

[Marek Marczykowski-Górecki <marmarek@xxxxxxxxxxxxxxxxxxxxxx>]

On Tue, Jun 16, 2026 at 11:13:33AM +0100, Frediano Ziglio wrote:
> From: Frediano Ziglio <frediano.ziglio@xxxxxxxxx>
> 
> Required by UEFI CA memory mitigation.
> 
> It is a requirement for NX_COMPAT so the PE can be loaded with W^X perms
> in the pagetables.
> 
> NX_COMPAT is a requirement from shim-review,
> https://github.com/rhboot/shim-review#do-you-have-the-nx-bit-set-in-your-shim-if-so-is-your-entire-boot-stack-nx-compatible-and-what-testing-have-you-done-to-ensure-such-compatibility
> 
> Sections with different permissions must be in separate pages.
> In the case of debug sections they are contiguous and have the same
> permissions so it's not an issue if they are not aligned to the page.
> 
> Signed-off-by: Frediano Ziglio <frediano.ziglio@xxxxxxxxxx>

Acked-by: Marek Marczykowski-Górecki <marmarek@xxxxxxxxxxxxxxxxxxxxxx>

> --
> Changes since v1:
> - Change subject.
> 
> Changes since v2:
> - Improved commit message and subject.
> ---
>  xen/arch/x86/xen.lds.S | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/xen/arch/x86/xen.lds.S b/xen/arch/x86/xen.lds.S
> index b9e888e596..f758940674 100644
> --- a/xen/arch/x86/xen.lds.S
> +++ b/xen/arch/x86/xen.lds.S
> @@ -162,8 +162,8 @@ SECTIONS
>         __note_gnu_build_id_end = .;
>    } PHDR(note) PHDR(text)
>  #elif defined(BUILD_ID_EFI)
> -  /* Workaround bug in binutils < 2.36 */
> -  . = ALIGN(32);
> +  /* Align to satisfy UEFI CA memory mitigation. */
> +  . = ALIGN(PAGE_SIZE);
>    DECL_SECTION(.buildid) {
>         __note_gnu_build_id_start = .;
>         *(.buildid)
> @@ -330,6 +330,7 @@ SECTIONS
>    __2M_rwdata_end = ALIGN(SECTION_ALIGN);
>  
>  #ifdef EFI
> +  . = ALIGN(PAGE_SIZE);
>    .reloc ALIGN(4) : {
>      __base_relocs_start = .;
>      *(.reloc)
> -- 
> 2.43.0
> 

-- 
Best Regards,
Marek Marczykowski-Górecki
Invisible Things Lab

Attachment: signature.asc
Description: PGP signature