Messages in this thread | | | Subject | Re: [patch v2 3/8] KVM: x86: add Intel processor trace virtualization mode | From | Paolo Bonzini <> | Date | Mon, 13 Nov 2017 17:32:00 +0100 |
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On 30/10/2017 23:05, Luwei Kang wrote: > + if (!(_cpu_based_2nd_exec_control & SECONDARY_EXEC_PT_USE_GPA) || > + !(_vmexit_control & VM_EXIT_CLEAR_IA32_RTIT_CTL) || > + !(_vmentry_control & VM_ENTRY_LOAD_IA32_RTIT_CTL)) { > + _cpu_based_2nd_exec_control &= ~SECONDARY_EXEC_PT_USE_GPA;
Also, you are not checking anywhere if the SUPPRESS_PIP controls are available. This is probably the best place.
> + _vmexit_control &= ~VM_EXIT_CLEAR_IA32_RTIT_CTL; > + _vmentry_control &= ~VM_ENTRY_LOAD_IA32_RTIT_CTL;
These two are not needed; disabling SECONDARY_EXEC_PT_USE_GPA is enough. The tracing mode will revert to PT_SYSTEM, which does not use the load/clear RTIT_CTL controls.
Paolo
> + } > +
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