Re: [PATCH v11 00/26] Drivers for gunyah hypervisor

[Alex Elder]

On 3/3/23 7:06 PM, Elliot Berman wrote:
> Gunyah is a Type-1 hypervisor independent of any
> high-level OS kernel, and runs in a higher CPU privilege level. It does
> not depend on any lower-privileged OS kernel/code for its core
> functionality. This increases its security and can support a much smaller
> trusted computing base than a Type-2 hypervisor.
>
> Gunyah is an open source hypervisor. The source repo is available at
> https://github.com/quic/gunyah-hypervisor.

I've done a pretty detailed review again, and got further along
than I did last time.  Things are definitely looking better, but
I have found some bugs that need to be addressed.

I also make a lot of comments about grouping certain sets of
definitions into enumerated types.  Also I tend to notice when
things aren't done consistently, and I mention that a lot.

There are silly suggestions all over about alignment of
things--these are mainly to make the code look prettier,
though that's a matter of opinion.

I still prefer having lines generally closer to 80 columns
wide, but I've already mentioned that...

I really focused on the code, and not the documentation.
In fact I didn't even pay much attention to your patch
headers either.  I did not review the SCM calls yet.

So in summary I have not reviewed patches 1, 2, 16, 17,
and 26.  I try to look at everything in my next review,
which I hope will be final (or very close).

					-Alex

> The diagram below shows the architecture.
>
> ::
>
>           VM A                    VM B
>       +-----+ +-----+  | +-----+ +-----+ +-----+
>       |     | |     |  | |     | |     | |     |
>   EL0 | APP | | APP |  | | APP | | APP | | APP |
>       |     | |     |  | |     | |     | |     |
>       +-----+ +-----+  | +-----+ +-----+ +-----+
>   ---------------------|-------------------------
>       +--------------+ | +----------------------+
>       |              | | |                      |
>   EL1 | Linux Kernel | | |Linux kernel/Other OS |   ...
>       |              | | |                      |
>       +--------------+ | +----------------------+
>   --------hvc/smc------|------hvc/smc------------
>       +----------------------------------------+
>       |                                        |
>   EL2 |            Gunyah Hypervisor           |
>       |                                        |
>       +----------------------------------------+
>
> Gunyah provides these following features.

. . .