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Subject: Re: [Tee-dev] [PATCHv8 1/3] optee: use uuid for sysfs driver entry
From:   James Bottomley <James.Bottomley@HansenPartnership.com>
To:     Sumit Garg <sumit.garg@linaro.org>
Cc:     Jerome Forissier <jerome@forissier.org>,
        Maxim Uvarov <maxim.uvarov@linaro.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
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        Jason Gunthorpe <jgg@ziepe.ca>,
        linux-integrity@vger.kernel.org, peterhuewe@gmx.de
Date:   Wed, 24 Jun 2020 08:21:09 -0700
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On Wed, 2020-06-24 at 16:17 +0530, Sumit Garg wrote:
> Apologies for delay in my reply as I was busy with some other stuff.
> 
> On Fri, 19 Jun 2020 at 20:30, James Bottomley
> <James.Bottomley@hansenpartnership.com> wrote:
[...]
> > it's about consistency with what the kernel types mean.  When some
> > checker detects your using little endian operations on a big endian
> > structure (like in the prink for instance) they're going to keep
> > emailing you about it.
> 
> As mentioned above, using different terminology is meant to cause
> more confusion than just difference in endianness which is manageable
> inside TEE.
> 
> And I think it's safe to say that the kernel implements UUID in big
> endian format and thus uses %pUb whereas OP-TEE implements UUID in
> little endian format and thus uses %pUl.

So what I think you're saying is that if we still had uuid_be and
uuid_le you'd use uuid_le, because that's exactly the structure
described in the docs.  But because we renamed

uuid_be -> uuid_t
uuid_le -> guid_t

You can't use guid_t as a kernel type because it has the wrong name?

James