ACK: [PATCH] fwts/madt: Remove TODO for x2apic > 255 check

Colin Ian King colin.king at canonical.com
Thu Jul 21 15:35:51 UTC 2016


On 21/07/16 16:34, Prarit Bhargava wrote:
> The x2apic ID can be a 32-bit value starting from 0.  The TODO was likely
> introduced by this comment in section 5.2.12.12, of the ACPI6.0
> specification:
> 
> "Note: [Compatibility note] On some legacy OSes, Logical processors with APIC
> ID values less than 255 (whether in XAPIC or X2 APIC mode) must use the
> Processor Local APIC structure to convey their APIC information to OSPM, and
> those processors must be declared in the DSDT using the Processor() keyword.
> Logical processors with APIC ID values 255 and greater must use the Processor
> Local x2APIC structure and be declared using the Device() keyword. See Section
> 19.6.102 "Processor (Declare Processor)" for more information."
> 
> This does not mean that the lower bound of the x2apic ID is 255, rather
> that there are older OSes that will only interpret the lapic struct for
> x[2]apic IDs 0-255, and will interpret the x2apic struct for x2apic IDs
> greater than 255.
> 
> Signed-off-by: Prarit Bhargava <prarit at redhat.com>
> ---
>  src/acpi/madt/madt.c |    2 --
>  1 file changed, 2 deletions(-)
> 
> diff --git a/src/acpi/madt/madt.c b/src/acpi/madt/madt.c
> index e260222a8b75..b2d636c1d9d3 100644
> --- a/src/acpi/madt/madt.c
> +++ b/src/acpi/madt/madt.c
> @@ -802,8 +802,6 @@ static int madt_local_x2apic(fwts_framework *fw,
>  			    "reserved and properly set to zero.",
>  			    madt_sub_names[hdr->type]);
>  
> -	/* TODO: do we need to verify that the x2APIC ID is > 255? */
> -
>  	if (lx2apic->flags & 0xfffffffe)
>  		fwts_failed(fw, LOG_LEVEL_MEDIUM,
>  			    "MADTX2APICFlagsNonZero",
> 
Acked-by: Colin Ian King <colin.king at canonical.com>



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