Re: [kvm-unit-tests PATCH v3 04/11] lib: x86: Import insn decoder from Linux

[Sean Christopherson <seanjc@google.com>]

On Thu, Aug 25, 2022, Vasant Karasulli wrote:
>      There is at least one test that I know uses string IO i.e. x86/amd_sev.c.

That one should be easy to convert to directly do #VMGEXIT when SEV-ES is enabled.
Or maybe delete it an enlighten emulator.c's version?

>      I will check if there are more.

Tests that explicitly validate string I/O aren't all that interesting, we really
only need one string I/O test for SEV-ES.  I supposed one could make the argument
that it'd be useful to ensure that string I/O generates #VC as expected, but that
can be done without actually decoding the I/O.

Hmm, or cheat.  E.g. write up a dedicated #VC handler in x86/amd_sev.c for the
string I/O test to forward the #VMGEXIT, but rely on the existing checks in
test_stringio() to ensure it was done correctly.  That way there's no need to do
fancy decoding, but the "spirit" of the test is kept intact.