On 13/06/2016 09:55, Haozhong Zhang wrote: > Currently, only VMX bits (bit 1 & 2), LMCE bit (bit 20) as well as > lock bit (bit 0) in MSR_IA32_FEATURE_CONTROL are used for guest. The > availability of features indicated by those bits (except the lock bit) > can be discovered from cpuid and other MSR, so it looks not necessary > to publish them via fw_cfg. Or do you have other concerns? I would prefer to avoid having to change the firmware (SeaBIOS and OVMF) every time a new bit is added. Using fw_cfg makes it possible to develop the feature in the firmware once and for all. Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html