[Qemu-devel] [RFC v3 01/35] pc_piix: Add missing compat code to pc-0.1[0123]

[Eduardo Habkost <ehabkost@redhat.com>]

pc-0.13 and older were missing some compat code that is present on newer
machine-types:

* x86_cpu_compat_disable_kvm_features(FEAT_1_ECX, CPUID_EXT_X2APIC);
  (pc-i440fx-1.7 and older)
* x86_cpu_compat_set_features("n270", FEAT_1_ECX, 0, CPUID_EXT_MOVBE);
  (pc-i440fx-1.4 and older)
* x86_cpu_compat_set_features("Westmere", FEAT_1_ECX, 0, CPUID_EXT_PCLMULQDQ);
  (pc-i440fx-1.4 and older)

Add those missing bits to pc_init_pci_no_kvmclock(), to make sure
pc-0.13 and older are compatible with the older QEMU versions. While at
it, reorder pc_init_pci_no_kvmclock() and document where each line is
was copied from.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 hw/i386/pc_piix.c | 25 ++++++++++++++++++++-----
 1 file changed, 20 insertions(+), 5 deletions(-)

diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
index 2dccb34..802cd1a 100644
--- a/hw/i386/pc_piix.c
+++ b/hw/i386/pc_piix.c
@@ -389,16 +389,31 @@ static void pc_init_pci_1_2(MachineState *machine)
 /* PC init function for pc-0.10 to pc-0.13, and reused by xenfv */
 static void pc_init_pci_no_kvmclock(MachineState *machine)
 {
-    has_pci_info = false;
-    has_acpi_build = false;
-    smbios_defaults = false;
-    gigabyte_align = false;
+    /* Copy from pc_compat_2_0(): */
     smbios_legacy_mode = true;
     has_reserved_memory = false;
+
+    /* Copy from pc_compat_1_7(): */
+    smbios_defaults = false;
+    gigabyte_align = false;
     option_rom_has_mr = true;
+    x86_cpu_compat_disable_kvm_features(FEAT_1_ECX, CPUID_EXT_X2APIC);
+
+    /* Copy from pc_compat_1_6(): */
+    has_pci_info = false;
     rom_file_has_mr = false;
-    x86_cpu_compat_disable_kvm_features(FEAT_KVM, KVM_FEATURE_PV_EOI);
+    has_acpi_build = false;
+
+    /* Copy from pc_compat_1_4(): */
+    x86_cpu_compat_set_features("n270", FEAT_1_ECX, 0, CPUID_EXT_MOVBE);
+    x86_cpu_compat_set_features("Westmere", FEAT_1_ECX, 0, CPUID_EXT_PCLMULQDQ);
+
+    /* Copy from pc_compat_1_3(): */
     enable_compat_apic_id_mode();
+
+    /* Copy from pc_compat_1_2(): */
+    x86_cpu_compat_disable_kvm_features(FEAT_KVM, KVM_FEATURE_PV_EOI);
+
     pc_init1(machine, 1, 0);
 }
 
-- 
1.9.3