Re: [PATCH v3 12/21] x86/virt/tdx: Create TDMRs to cover all system RAM

[Dave Hansen]

On 4/29/22 00:24, Kai Huang wrote:
> On Thu, 2022-04-28 at 09:22 -0700, Dave Hansen wrote:
>> On 4/5/22 21:49, Kai Huang wrote:
>>> implies that one TDMR could cover multiple e820 RAM entries.  If a RAM
>>> entry spans the 1GB boundary and the former part is already covered by
>>> the previous TDMR, just create a new TDMR for the latter part.
>>>
>>> TDX only supports a limited number of TDMRs (currently 64).  Abort the
>>> TDMR construction process when the number of TDMRs exceeds this
>>> limitation.
>>
>> ... and what does this *MEAN*?  Is TDX disabled?  Does it throw away the
>> RAM?  Does it eat puppies?
> 
> How about:
> 
> 	TDX only supports a limited number of TDMRs.  Simply return error when
> 	the number of TDMRs exceeds the limitation.  TDX is disabled in this
> 	case.

Better, but two things there that need to be improved.  This is a cover
letter.  Talking at the function level ("return error") is too
low-level.  It's also slipping into passive mode "is disabled".  Fixing
those, it looks like this:

	TDX only supports a limited number of TDMRs.  Disable TDX if all
	TDMRs are consumed but there is more RAM to cover.