On 13/05/22 17:46, Andi Kleen wrote: > Adrian Hunter <adrian.hunter@xxxxxxxxx> writes: > >> A common case for KVM test programs is that the guest object code can be >> found in the hypervisor process (i.e. the test program running on the >> host). To support that, a new option "--guest-code" has been added in >> previous patches. >> >> In this patch, add support also to Intel PT. >> >> In particular, ensure guest_code thread is set up before attempting to >> walk object code or synthesize samples. > > Can you make it clear in the documentation what parts runs on the host > and what parts on the guest? That is up to the test program. All the host thread maps are copied, so perf tools doesn't have to know. > > I'm still not fully sure how it exactly finds the code on the host, > how is the code transferred? I don't know. From a quick look at the code in tools/testing/selftests/kvm/lib/kvm_util.c it seems to be using KVM_SET_USER_MEMORY_REGION IOCTL. > > Other than that more support for this use case is very useful. > > -Andi
