Re: MSRs load/store
On 12/07/2009 05:32 PM, Jiaqing Du wrote: Hi Avi, I did not get your point. But if we want to multiplex some of the MSRs across the VMM and the guest(s), it would be handy if the hardware provides this feature: save host's version and load guest's version. Of course, we can do this manually. I'm just wondering why this feature is missing. Well, you'll have to ask the designers of the feature. If it can be done manually, why add a feature in hardware? -- error compiling committee.c: too many arguments to function -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: MSRs load/store
Hi Avi, I did not get your point. But if we want to multiplex some of the MSRs across the VMM and the guest(s), it would be handy if the hardware provides this feature: save host's version and load guest's version. Of course, we can do this manually. I'm just wondering why this feature is missing. Thanks, Jiaqing 2009/12/7 Avi Kivity : > On 12/07/2009 05:07 PM, Jiaqing Du wrote: >> >> Hi List, >> >> My question is about VM-Exit& VM-Entry controls for MSRs on Intel's >> processors. >> >> For VM-Exit, a VMM can specify lists of MSRs to be stored and loaded >> on VM exits. But for VM-Entry, a VMM can only specify a list of MSRs >> to be loaded on VM entries. Why does not the processor have the >> feature that stores MSRs before loading new ones for VM entries? >> > > Presumably the host knows what values are in those MSRs, so it doesn't need > to store them. > > -- > error compiling committee.c: too many arguments to function > > -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: MSRs load/store
On 12/07/2009 05:07 PM, Jiaqing Du wrote: Hi List, My question is about VM-Exit& VM-Entry controls for MSRs on Intel's processors. For VM-Exit, a VMM can specify lists of MSRs to be stored and loaded on VM exits. But for VM-Entry, a VMM can only specify a list of MSRs to be loaded on VM entries. Why does not the processor have the feature that stores MSRs before loading new ones for VM entries? Presumably the host knows what values are in those MSRs, so it doesn't need to store them. -- error compiling committee.c: too many arguments to function -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
MSRs load/store
Hi List, My question is about VM-Exit & VM-Entry controls for MSRs on Intel's processors. For VM-Exit, a VMM can specify lists of MSRs to be stored and loaded on VM exits. But for VM-Entry, a VMM can only specify a list of MSRs to be loaded on VM entries. Why does not the processor have the feature that stores MSRs before loading new ones for VM entries? Thanks, Jiaqing -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html