Re: [RFC PATCH v2 00/24] KVM: combined patchset for MBEC/GMET support

[Jon Kohler]

> On Mar 26, 2026, at 2:16 PM, Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote:
> 
> This series introduces support for two related features that Hyper-V uses
> in its implementation of Virtual Secure Mode; these are Intel Mode-Based
> Execute Control and AMD Guest Mode Execution Trap.
> 
> It's still RFC because it can definitely use more testing and review,
> but I'm pretty confident with the overall shape and design.

I've tested this on both Intel and AMD in our 6.18.y based tree and
everything works as expected, and we're very happy with performance
thus far. 

I've also ran the kvm-unit-tests series on both Intel/AMD and thats
also working as expected. I proposed a few more SVM tests off-list, so
we'll see if that helps increase coverage a pinch more.

Guest:
Windows 11 25H2 OS Build 26200.8037

AMD proc:
AMD EPYC 9745 (Turin/Zen5)

Intel proc:
Intel(R) Xeon(R) Gold 6426Y (SPR)

For this RFCv2 series:
Tested-By: Jon Kohler <jon@xxxxxxxxxxx>

On the ecosystem enablement side, qemu has both mbec [1] and gmet [2];
however, they are not exposed via any model definitions (yet), so users
would need to manually enable them in the short term. I'll work up 
a patch to expose these via model definitions and propose that to the
list this week.

[1] https://github.com/qemu/qemu/commit/bfff4b2ae5452463ab8c14b4a8a020288b5ff5d8
[2] https://github.com/qemu/qemu/commit/746a823a17f25393cc8c0cd1257f6dcef757bc09