Re: [PATCH v10 05/16] x86/virt/tdx: Add skeleton to enable TDX on demand

[Huang, Kai]

On Thu, 2023-03-23 at 15:12 -0700, Hansen, Dave wrote:
> On 3/23/23 15:09, Huang, Kai wrote:
> > 1) In TDH.SYS.INIT, ask TDX module team to return TDX_RND_NO_ENTROPY instead of
> > TDX_SYS_BUSY when running out of entropy.
> > 
> > 2) In TDH.SYS.KEY.CONFIG, ask TDX module to return TDX_RND_NO_ENTROPY instead of
> > TDX_KEY_GENERATION_FAILED when running out of entropy.  Whether
> > TDX_KEY_GENERATION_FAILED should be still kept is  up to TDX module team
> > (because it looks running concurrent PCONFIGs is also related).
> > 
> > 3) Ask TDX module to always return TDX_RND_NO_ENTROPY in _ALL_ SEAMCALLs and
> > keep this behaviour for future TDX modules too.
> 
> Yes, that's all fine.
> 
> > 4) In the common seamcall(), retry on TDX_RND_NO_ENTROPY.
> > 
> > In terms of how many times to retry, I will use a fixed value for now, similar
> > to the kernel code below:
> > 
> > #define RDRAND_RETRY_LOOPS      10
> 
> Heck, you could even just use RDRAND_RETRY_LOOPS directly.  It's
> hard(er) to bikeshed your choice of a random number that you didn't even
> pick.

Yes I'll just include the header and use it.  Thanks.