On Thu, Oct 20, 2022, Xiaoyao Li wrote: > vcpu->arch.mcg_cap represents the value of MSR_IA32_MCG_CAP. It's > set via ioctl(KVM_X86_SETUP_MCE) from userspace when exposing and > configuring MCE to guest. > > It's wrong to leave the default value as KVM_MAX_MCE_BANKS. Why? I agree it's an odd default, but the whole MCE API is odd. Functionally, I don't see anything that's broken by allowing the guest to access the MCx_CTL MSRs by default.
