On 07/06/2018 15:26, Alexander Shishkin wrote: >> Intel PT virtualization can be work in one of 2 possible modes: >> a. system-wide: trace both host and guest and output to host buffer; >> b. host-guest: trace host/guest simultaneous and output to their >> respective buffer. > > I think we discussed this before. That's not the choice that the user > needs to make. The only choice that I see is what happens if the guest > wants to use PT while it's already in use by the host. Otherwise, each > of them gets to use PT as they would. That is a superset of this choice: a. hide PT from guests completely (the "a" above) b. host-guest with guest preference: same as "b" above c. host-guest with host preference: trace host/guest simultaneously, but drop guest events if the host has tracing enabled. so I don't think this choice is an issue. Paolo
