On 20/01/2016 18:31, 'Roman Kagan' wrote: > On Wed, Jan 20, 2016 at 06:02:25PM +0100, Paolo Bonzini wrote: >> >> >> On 20/01/2016 16:20, 'Roman Kagan' wrote: >>>>> So we should not add a new exit >>> Why? VCPU exit codes are not a scarse resource. >> >> Indeed, but grouping makes things easier to understand. >> >>> So far we've envisaged two reasons for VCPU exit related to hyper-v: one >>> for hyper-v MSRs and the other for hypercalls. Since there was a >>> discussion on implementing generic MSR access by Peter we thought it >>> wiser to introduce a new VCPU exit for hyper-v hypercalls to avoid >>> interfering with the MSR implementation. >> >> That's a good idea. However, I think I'm not going to accept the MSR >> exit feature, and then the current Hyper-V exit API makes some sense >> indeed (it's just 3 values, transferring them all at once is not >> expensive at all). > > OK can we please sum up (as I'm now a bit confused) what we do now: > > 1) use a single vcpu exit for both Hyper-V cases (which implies we need > to fix this patchset to add the subcode for hypercalls) This. Paolo > or > > 2) use individual vcpu exits for Hyper-V MSRs and for Hyper-V hypercalls > (which implies we need to submit an incremental patch dropping the > subcode from Hyper-V MSR exit and renaming it to better describe the > reality)? > > Thanks, > Roman. > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html