Re: [PATCH v5 3/3] x86/tdx: Add Quote generation support

From: Kai Huang
Date: Tue May 03 2022 - 18:13:16 EST


On Mon, 2022-05-02 at 19:39 -0700, Sathyanarayanan Kuppuswamy wrote:
> >
> > Using vmap() we can still (almost) avoid private/shared conversion at IOCTL
> > time
> > by allocating a default size buffer (which is large enough to cover 99%
> > cases,
> > etc) at driver initialization time:
>
> Allocating fixed size buffer pool will work for dma buffer allocation
> as well.
>
> So the comparison is between platform driver boilerplate code vs vmap
> and shared/unshared code addition. It is arguable which is better. I
> think it is about preference.

Not really. DMA buffer is guaranteed to be shared for now, but it's not
guaranteed in the future generations of TDX.

--
Thanks,
-Kai