RE: [PATCH v3 11/13] x86/smpboot: Add a helper get the address of the wakeup mailbox

[Michael Kelley]

From: Ricardo Neri <ricardo.neri-calderon@xxxxxxxxxxxxxxx> Sent: Saturday, May 3, 2025 12:15 PM
> 
> A Hyper-V VTL level 2 guest on a TDX environment needs to map the
> physical page of the ACPI Multiprocessor Wakeup Structure as private
> (encrypted). It needs to know the physical address of this structure.
> Add a helper function.
> 
> Suggested-by: Michael Kelley <mhklinux@xxxxxxxxxxx>
> Signed-off-by: Ricardo Neri <ricardo.neri-calderon@xxxxxxxxxxxxxxx>
> ---
> Changes since v2:
>  - Introduced this patch
> 
> Changes since v1:
>  - N/A
> ---
>  arch/x86/include/asm/smp.h | 1 +
>  arch/x86/kernel/smpboot.c  | 5 +++++
>  2 files changed, 6 insertions(+)
> 
> diff --git a/arch/x86/include/asm/smp.h b/arch/x86/include/asm/smp.h
> index 97bfbd0d24d4..18003453569a 100644
> --- a/arch/x86/include/asm/smp.h
> +++ b/arch/x86/include/asm/smp.h
> @@ -149,6 +149,7 @@ static inline struct cpumask *cpu_l2c_shared_mask(int cpu)
>  #ifdef CONFIG_X86_64
>  void setup_mp_wakeup_mailbox(u64 addr);
>  struct acpi_madt_multiproc_wakeup_mailbox *get_mp_wakeup_mailbox(void);
> +u64 get_mp_wakeup_mailbox_paddr(void);
>  #endif
> 
>  #else /* !CONFIG_SMP */
> diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
> index 6f39ebe4d192..1e211c78c1d3 100644
> --- a/arch/x86/kernel/smpboot.c
> +++ b/arch/x86/kernel/smpboot.c
> @@ -1431,4 +1431,9 @@ struct acpi_madt_multiproc_wakeup_mailbox
> *get_mp_wakeup_mailbox(void)
>  {
>  	return acpi_mp_wake_mailbox;
>  }
> +
> +u64 get_mp_wakeup_mailbox_paddr(void)
> +{
> +	return acpi_mp_wake_mailbox_paddr;
> +}
>  #endif
> --
> 2.43.0

Reviewed-by: Michael Kelley <mhklinux@xxxxxxxxxxx>