Re: [Qemu-devel] [PATCH v3 1/2] target-i386: KVM: add basic Intel LMCE support

[Haozhong Zhang]

On 06/13/16 10:33, Paolo Bonzini wrote:
> 
> 
> 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.
> 

Thanks for the explanation! Is it proper to add a key in fw_cfg for
this purpose, e.g FW_CFG_MSR_FEATURE_CONTROL to pass bits that are
supposed to be set by firmware?

Thanks,
Haozhong