Messages in this thread | | | Subject | Re: [PATCH v9 06/12] KVM: x86: Add Intel Processor Trace virtualization mode | From | Paolo Bonzini <> | Date | Mon, 11 Jun 2018 13:39:39 +0200 |
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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
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