On 15/01/2018 08:19, Kang, Luwei wrote: >> If you are forwarding host info directly to the guest, the feature >> is not migration-safe. The new feature needs to be added to >> feature_word_info[FEAT_7_0_EBX].unmigratable_flags. >> > Hi, Thanks for you review. I want to support Intel PT live migration > and patch [2/2] to do this. I don't understand why need to add this > feature in feature_word_info[FEAT_7_0_EBX].unmigratable_flags first > to disable live migration. Hi Luwei, the issue is that different hosts can have different CPUID flags. You don't have a way to set the CPUID flags from the "-cpu" command line, and it's not clear what values will be there in the various Ice Lake SKUs. I am not sure if there is a mechanism to allow live migration only for "-cpu host", but it cannot be supported for any other "-cpu" model. Paolo
