Re: [RFC PATCH v3 2/3] x86/acpi: Integrate BGRT preservation with status reporting

[Andrew Cooper <andrew.cooper3@xxxxxxxxxx>]

On 12/03/2026 11:14 am, Soumyajyotii Ssarkar wrote:
> diff --git a/xen/arch/x86/acpi/boot.c b/xen/arch/x86/acpi/boot.c
> index 1ca2360e00..20afe79db9 100644
> --- a/xen/arch/x86/acpi/boot.c
> +++ b/xen/arch/x86/acpi/boot.c
>  static int __init cf_check acpi_invalidate_bgrt(struct acpi_table_header 
> *table)
>  {
>       struct acpi_table_bgrt *bgrt_tbl =
> @@ -754,5 +760,7 @@ int __init acpi_boot_init(void)
>
>       acpi_table_parse(ACPI_SIG_BGRT, acpi_invalidate_bgrt);
>
> +     efi_bgrt_status_info();

To help with your build failure, given this call from outside EFI code,
you need...

> +
>       return 0;
>  }
> diff --git a/xen/common/efi/boot.c b/xen/common/efi/boot.c
> index e6451130ce..68e06d707c 100644
> --- a/xen/common/efi/boot.c
> +++ b/xen/common/efi/boot.c
> @@ -1911,6 +1911,22 @@ static bool __init cf_check rt_range_valid(unsigned 
> long smfn, unsigned long emf
>      return true;
>  }
>
> +void __init efi_bgrt_status_info(void)
> +{
> +    if ( !efi_enabled(EFI_BOOT) )
> +        return;
> +
> +    if ( bgrt_info.preserved )
> +    {
> +        printk(XENLOG_INFO "EFI: BGRT image preserved: %lu KB\n",
> +               bgrt_info.size / 1024);
> +        printk(XENLOG_INFO "EFI: BGRT relocated from %p to %p\n",
> +               bgrt_info.old_addr, bgrt_info.new_addr);
> +    }
> +    else if ( bgrt_info.failure_reason[0] )
> +        printk(XENLOG_WARNING "EFI: BGRT preservation failed: %s\n",
> +               bgrt_info.failure_reason);
> +}

... a matching stub function in xen/common/efi/common-stub.c

xen.efi is constructed by taking non-efi Xen and linking in a few more
object files.  It is not a full rebuild with different toolchain settings.

~Andrew