On Thu, Jun 16, 2022 at 04:46:40AM -0400, Yang Weijiang wrote: > Set the feature bits so that CET capabilities can be seen in guest via > CPUID enumeration. Add CR4.CET bit support in order to allow guest set CET > master control bit(CR4.CET). > > Disable KVM CET feature if unrestricted_guest is unsupported/disabled as > KVM does not support emulating CET. > > Don't expose CET feature if dependent CET bits are cleared in host XSS, > or if XSAVES isn't supported. Updating the CET features in common x86 is > a little ugly, but there is no clean solution without risking breakage of > SVM if SVM hardware ever gains support for CET, e.g. moving everything to > common x86 would prematurely expose CET on SVM. The alternative is to > put all the logic in VMX, but that means rereading host_xss in VMX and > duplicating the XSAVES check across VMX and SVM. Doesn't Zen3 already have SHSTK ?
