Re: [kvm-unit-tests PATCH 1/3] x86: Add define for MSR_IA32_PRED_CMD's PRED_CMD_IBPB (bit 0)

[Sean Christopherson <seanjc@google.com>]

On Thu, Mar 30, 2023, Xiaoyao Li wrote:
> On 3/30/2023 12:36 AM, Sean Christopherson wrote:
> > On Wed, Mar 29, 2023, Xiaoyao Li wrote:
> > > On 3/28/2023 11:07 PM, Sean Christopherson wrote:
> > > > On Tue, Mar 28, 2023, Xiaoyao Li wrote:
> > > > > On 3/28/2023 1:02 PM, Sean Christopherson wrote:
> > > > > > Add a define for PRED_CMD_IBPB and use it to replace the open coded '1' in
> > > > > > the nVMX library.
> > > > > What does nVMX mean here?
> > > > Nested VMX.  From KUT's perspective, the testing exists to validate KVM's nested
> > > > VMX implementation.  If it's at all confusing, I'll drop the 'n'  And we've already
> > > > established that KUT can be used on bare metal, even if that's not the primary use
> > > > case.
> > > So vmexit.flat is supposed to be ran in L1 VM?
> > Not all of the tests can be run on bare metal, e.g. I can't imagine the VMware
> > backdoor test works either.
> > 
> 
> Sorry, I think neither I ask clearly nor you got my point.
> 
> You said "the testing exists to validate KVM's nested VMX implementation".
> So I want to know what's the expected usage to run vmexit.flat.
> 
> If for nested, we need to first boot a VM and then inside the VM we run the
> vmexit.flat with QEMU, right?
> 
> That's what confuses me. Isn't vmexit.flat supposed to be directly used on
> the host with QEMU? In this case, nothing to do with nested.

Oof, my bad, I had a literacy problem.  I somehow read "vmx.c" instead of "vmexit.c",
and never picked up on what you were saying.  I'll fix the changelog.