Re: [PATCH 4/7] kvm: vmx: Set IBPB when running a different VCPU

From: Paolo Bonzini
Date: Tue Jan 09 2018 - 03:34:01 EST


On 08/01/2018 20:36, Jim Mattson wrote:
> Shouldn't there be an IBPB on *any* context switch away from a VCPU
> thread, even if it is to a non-VCPU thread?

Yes, but that's the task of patches to the generic Linux context
switching code. As mentioned in the cover letter, this isn't yet a full
solution---just the KVM bits, which is what Radim and I have full
control on. Hence the hacks with cpuid in local bools.

Paolo