[Qemu-devel] [PATCH v4 11/17] target-i386: Use Hypervisor vendor in -machine pc, accel=tcg.

[Don Slutz]

Also known as Paravirtualization vendor.

This change is based on:

Microsoft Hypervisor CPUID Leaves:
  
http://msdn.microsoft.com/en-us/library/windows/hardware/ff542428%28v=vs.85%29.aspx

Linux kernel change starts with:
  http://fixunix.com/kernel/538707-use-cpuid-communicate-hypervisor.html
Also:
  http://lkml.indiana.edu/hypermail/linux/kernel/1205.0/00100.html
This is where the 0 is the same as 0x40000001 is defined.

VMware documention on CPUIDs (Mechanisms to determine if software is
running in a VMware virtual machine):
  
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1009458

Signed-off-by: Don Slutz <address@hidden>
---
 target-i386/cpu.c |   20 ++++++++++++++------
 target-i386/cpu.h |    2 ++
 2 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/target-i386/cpu.c b/target-i386/cpu.c
index d8f7e22..5cf7146 100644
--- a/target-i386/cpu.c
+++ b/target-i386/cpu.c
@@ -1693,10 +1693,18 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, 
uint32_t count,
             }
         }
     } else if (index & 0x40000000) {
-        if (env->cpuid_hv_level > 0) {
+        if (env->cpuid_hv_level != 0 ||
+            env->cpuid_hv_vendor1 != 0 ||
+            env->cpuid_hv_vendor2 != 0 ||
+            env->cpuid_hv_vendor3 != 0) {
+            uint32_t real_level = env->cpuid_hv_level;
+
+            /* Handle KVM's old level. */
+            if (real_level == 0)
+                real_level = CPUID_HV_LEVEL_KVM;
             /* Handle Hypervisor CPUIDs */
-            if (index > env->cpuid_hv_level) {
-                index = env->cpuid_hv_level;
+            if (index > real_level) {
+                index = real_level;
             }
         } else {
             if (index > env->cpuid_level)
@@ -1842,9 +1850,9 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, 
uint32_t count,
         break;
     case 0x40000000:
         *eax = env->cpuid_hv_level;
-        *ebx = 0;
-        *ecx = 0;
-        *edx = 0;
+        *ebx = env->cpuid_hv_vendor1;
+        *ecx = env->cpuid_hv_vendor2;
+        *edx = env->cpuid_hv_vendor3;
         break;
     case 0x40000001:
         *eax = env->cpuid_kvm_features;
diff --git a/target-i386/cpu.h b/target-i386/cpu.h
index 91ddf76..e3e176b 100644
--- a/target-i386/cpu.h
+++ b/target-i386/cpu.h
@@ -492,6 +492,8 @@
 
 #define CPUID_HV_LEVEL_HYPERV  0x40000005
 
+#define CPUID_HV_LEVEL_KVM  0x40000001
+
 #define CPUID_MWAIT_IBE     (1 << 1) /* Interrupts can exit capability */
 #define CPUID_MWAIT_EMX     (1 << 0) /* enumeration supported */
 
-- 
1.7.1