Re: [PATCH v5 0/8] KVM: x86: Add CMCI and UCNA emulation

Jue Wang
2022-06-30T14:23:05Z

On Thu, Jun 30, 2022 at 6:48 AM Xiaoyao Li <xiaoyao.li@intel.com> wrote:
>
> On 6/11/2022 1:11 AM, Jue Wang wrote:
> > This patch series implement emulation for Corrected Machine Check
> > Interrupt (CMCI) signaling and UnCorrectable No Action required (UCNA)
> > error injection.
> >
>
> It seems the main purpose of this series is to allow UCNA error
> injection and notify it to guest via CMCI.
>
> But it doesn't emulate CMCI fully. E.g., guest's error threshold of
> MCi_CTL2 doesn't work. It's still controlled by host's value.
>
Both of the above points are correct.

In fact, this series does not enable injecting corrected errors into a
KVM guest at all, for:

1. It is not necessary since corrected errors are transparent to
software executions (host / guest).
2. Corrected errors can be fully managed on the host side (monitor, re-act).
3. Prevent guest initiated row-hammer attack based on the injected
corrected errors feedback loop.

Thanks,
-Jue