On Fri, Aug 20, 2021, Brijesh Singh wrote:

The setup_vmgexit_scratch() function may rely on a long-lived GHCB
mapping if the GHCB shared buffer area was used for the scratch area.
In preparation for eliminating the long-lived GHCB mapping, always
allocate a buffer for the scratch area so it can be accessed without
the GHCB mapping.

Would it make sense to post this patch and the next (Remove the long-lived GHCB
host map) in a separate mini-series?  It's needed for SNP, but AFAICT there's
nothing that depends on SNP.  Getting this merged ahead of time would reduce the
size of the SNP series by a smidge.