Re: [PATCH] xen/acpi: Don't fail if SPCR table is absent

[Jan Beulich <jbeulich@xxxxxxxx>]

On 22.10.2020 00:12, Elliott Mitchell wrote:
> --- a/xen/arch/arm/acpi/domain_build.c
> +++ b/xen/arch/arm/acpi/domain_build.c
> @@ -42,17 +42,18 @@ static int __init acpi_iomem_deny_access(struct domain *d)
>      status = acpi_get_table(ACPI_SIG_SPCR, 0,
>                              (struct acpi_table_header **)&spcr);
>  
> -    if ( ACPI_FAILURE(status) )
> +    if ( ACPI_SUCCESS(status) )
>      {
> -        printk("Failed to get SPCR table\n");
> -        return -EINVAL;
> +        mfn = spcr->serial_port.address >> PAGE_SHIFT;
> +        /* Deny MMIO access for UART */
> +        rc = iomem_deny_access(d, mfn, mfn + 1);
> +        if ( rc )
> +            return rc;
> +    }
> +    else
> +    {
> +        printk("Failed to get SPCR table, Xen console may be unavailable\n");
>      }

Nit: While I see you've got Stefano's R-b already, I Xen we typically
omit the braces here.

Jan