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