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Date:   Wed, 11 Oct 2023 16:32:34 -0700
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Subject: Re: [PATCH v4 14/15] asm-generic: hyperv: Use new Hyper-V headers
 conditionally.
To:     Alex Ionescu <aionescu@gmail.com>
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From:   Nuno Das Neves <nunodasneves@linux.microsoft.com>
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On 10/5/2023 12:52 PM, Alex Ionescu wrote:
>>> 3) Truly making hypertv-tlfs the "documented" header, and then > removing any duplication from HDK so that it remains the
>>> "undocumented" header file. In this manner, one would include
>>> hyperv-tlfs to use the stable ABI, and they would include HDK (which
>>> would include hyperv-tlfs) to use the unstable+stable ABI.
>>
>> hyperv-tlfs.h is remaining the "documented" header.
>>
>> But, we can't make the HDK header depend on hyperv-tlfs.h, for 2 primary
>> reasons:
>> 1. We need to put the new HDK headers in uapi so that we can use them in
>> our IOCTL interface. As a result, we can't include hyperv-tlfs.h (unless
>> we put it in uapi as well).
>> 2. The HDK headers not only duplicate, but also MODIFY some structures
>> in hyperv-tlfs.h. e.g., The struct is in hyperv-tlfs.h, but a particular
>> field or bitfield is not.
> 
> #2 was something I was worried about. Do you know if the
> standards/docs team is planning on updating the TLFS at some point
> with updates on their end? At which point I'd assume you'd be OK with
> patches to add them to hyperv-tlfs.h
> 

I don't know the current plans for updating the TLFS. But yes, assuming
a new TLFS doc has something that is needed in the kernel, hyperv-tlfs.h
would be updated to support that.

Thanks,
Nuno