On 20/06/19 08:46, Xiaoyao Li wrote: >> >> It depends on whether or not processors support the 1-setting instead >> of “enable XSAVES/XRSTORS” is 1 in VM-exection control field. Anyway, > > Yes, whether this field exist or not depends on whether processors > support the 1-setting. > > But if "enable XSAVES/XRSTORS" is clear to 0, XSS_EXIT_BITMAP doesn't > work. I think in this case, there is no need to set this vmcs field? vmx->secondary_exec_control can change; you are making the code more complex by relying on the value of the field at the point of vmx_vcpu_setup. I do _think_ your version is incorrect, because at this point CPUID has not been initialized yet and therefore vmx_compute_secondary_exec_control has not set SECONDARY_EXEC_XSAVES. However I may be wrong because I didn't review the code very closely: the old code is obvious and so there is no point in changing it. Paolo
