From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matt_Domsch@Dell.com Date: Tue, 11 Dec 2001 15:40:41 +0000 Subject: [Linux-ia64] RE: new GPT and uuid patches Message-Id: List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org OK, I'll look at it some more. > The *only* thing that needs to be endian aware is the > parsing/printing routines. Those will be EFI GUID specific and will > have to make up for the mistake Intel made when defining the external > representation in the weird mixed byteorder (well, I'm assuming it was > a mistake; I don't assume someone would willfully do such a thing ;-). It's these two conflicting things that I think can now be reconciled: EFI Spec references Wired for Management Baseline Spec 2.0: Page A-7 - section describing UUIDs and GUIDs (based on proposed RFC): In the absence of explicit application or presentation protocol specification to the contrary, a UUID is encoded as a 128-bit object, as follows: the fields are encoded as 16 octets, with the sizes and order of the fields defined in Section 3.1, and with each field encoded with the Most Significant Byte first (also known as network byte order). [big endian] Intel EFI Spec also has, in section 1.8.1: All implementations designed to conform to this specification will use "little endian" operation. If I read this right, I'd say that GUIDs are in fact big endian, even though the processor is in little-endian mode. Would Intel be willing to state this explicity in the EFI Spec, appendix A? Elsewhere in the spec, particularly in the PXE section, they do this already. > The other benefit is that this will make GUIDs identical to UUIDs > (which they ought be), except for the external representation. Hopefully now even the external representation can be identical. I'll work up a patch. Thanks, Matt -- Matt Domsch Sr. Software Engineer Dell Linux Solutions www.dell.com/linux #1 US Linux Server provider with 24% (IDC Sept 2001) #2 Worldwide Linux Server provider with 17% (IDC Sept 2001) #3 Unix provider with 18% in the US (Dataquest)!