On Thu, Dec 16, 2021 at 10:28:45AM -0600, Brijesh Singh wrote:

A good question; the GHCB page is needed only at the time of #VC.  If the
second stage VC handler is not called after the sev_enable() during the
decompression stage, setting up the GHC page in sev_enable() is a waste.

It would be a waste if no #VC would fire. But we set up a #VC handler so
we might just as well set up the GHCB for it too.

But in practice, the second stage VC handler will be called during
decompression. It also brings a similar question for the kernel
proper, should we do the same over there?

I'd think so, yes.
 

Jorge did the initial ES support and may have other reasons he chose to set
up GHCB page in the handler. I was trying to avoid the flow change. We can
do this as a pre or post-SNP patch; let me know your thoughts?

You can do a separate patch only with that change and if it causes
trouble, we can always debug/delay it.

Thx.

-- 
Regards/Gruss,
    Boris.

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