Re: [Qemu-devel] [PATCH v2] i386: Add new Hygon 'Dhyana' CPU model

[Pu Wen]

On 2019/4/15 17:25, Daniel P. Berrangé wrote:
> On Sat, Apr 13, 2019 at 10:54:40AM +0800, Pu Wen wrote:
...
> > diff --git a/hw/i386/pc.c b/hw/i386/pc.c
> > index f2c15bf..551bec9 100644
> > --- a/hw/i386/pc.c
> > +++ b/hw/i386/pc.c
> > @@ -128,6 +128,8 @@ GlobalProperty pc_compat_3_1[] = {
> >       { "EPYC" "-" TYPE_X86_CPU, "nrip-save", "off" },
> >       { "EPYC-IBPB" "-" TYPE_X86_CPU, "npt", "off" },
> >       { "EPYC-IBPB" "-" TYPE_X86_CPU, "nrip-save", "off" },
> > +    { "Dhyana" "-" TYPE_X86_CPU, "npt", "off" },
> > +    { "Dhyana" "-" TYPE_X86_CPU, "nrip-save", "off" },
> >       { "Skylake-Client" "-" TYPE_X86_CPU,      "mpx", "on" },
> >       { "Skylake-Client-IBRS" "-" TYPE_X86_CPU, "mpx", "on" },
> >       { "Skylake-Server" "-" TYPE_X86_CPU,      "mpx", "on" },
> > @@ -152,6 +154,7 @@ GlobalProperty pc_compat_2_12[] = {
> >       { TYPE_X86_CPU, "topoext", "off" },
> >       { "EPYC-" TYPE_X86_CPU, "xlevel", "0x8000000a" },
> >       { "EPYC-IBPB-" TYPE_X86_CPU, "xlevel", "0x8000000a" },
> > +    { "Dhyana-" TYPE_X86_CPU, "xlevel", "0x8000000a" },
> >   };
> >   const size_t pc_compat_2_12_len = G_N_ELEMENTS(pc_compat_2_12);
>
> You can drop the changes in this file. This CPU model didn't exist
> in any older QEMU releases, so there's no machine type backcompat
> required, at least from upstream QEMU POV.

Then how about running QEMU with the parameter like "-M pc-i440fx-2.12"? 
Although the default machine is newer than that.

--
Regards,
Pu Wen