1 files changed, 42 insertions, 8 deletions

diff --git a/target/i386/kvm/kvm-cpu.c b/target/i386/kvm/kvm-cpu.c
index 9c791b7b05..f76972e47e 100644
--- a/target/i386/kvm/kvm-cpu.c
+++ b/target/i386/kvm/kvm-cpu.c
@@ -18,10 +18,32 @@
 #include "kvm_i386.h"
 #include "hw/core/accel-cpu.h"
 
+static void kvm_set_guest_phys_bits(CPUState *cs)
+{
+    X86CPU *cpu = X86_CPU(cs);
+    uint32_t eax, guest_phys_bits;
+
+    eax = kvm_arch_get_supported_cpuid(cs->kvm_state, 0x80000008, 0, R_EAX);
+    guest_phys_bits = (eax >> 16) & 0xff;
+    if (!guest_phys_bits) {
+        return;
+    }
+    cpu->guest_phys_bits = guest_phys_bits;
+    if (cpu->guest_phys_bits > cpu->phys_bits) {
+        cpu->guest_phys_bits = cpu->phys_bits;
+    }
+
+    if (cpu->host_phys_bits && cpu->host_phys_bits_limit &&
+        cpu->guest_phys_bits > cpu->host_phys_bits_limit) {
+        cpu->guest_phys_bits = cpu->host_phys_bits_limit;
+    }
+}
+
 static bool kvm_cpu_realizefn(CPUState *cs, Error **errp)
 {
     X86CPU *cpu = X86_CPU(cs);
     CPUX86State *env = &cpu->env;
+    bool ret;
 
     /*
      * The realize order is important, since x86_cpu_realize() checks if
@@ -32,13 +54,15 @@ static bool kvm_cpu_realizefn(CPUState *cs, Error **errp)
      *
      * realize order:
      *
-     * x86_cpu_realize():
-     *  -> x86_cpu_expand_features()
-     *  -> cpu_exec_realizefn():
-     *            -> accel_cpu_common_realize()
-     *               kvm_cpu_realizefn() -> host_cpu_realizefn()
-     *  -> cpu_common_realizefn()
-     *  -> check/update ucode_rev, phys_bits, mwait
+     * x86_cpu_realizefn():
+     *   x86_cpu_expand_features()
+     *   cpu_exec_realizefn():
+     *      accel_cpu_common_realize()
+     *        kvm_cpu_realizefn()
+     *          host_cpu_realizefn()
+     *          kvm_set_guest_phys_bits()
+     *   check/update ucode_rev, phys_bits, guest_phys_bits, mwait
+     *   cpu_common_realizefn() (via xcc->parent_realize)
      */
     if (cpu->max_features) {
         if (enable_cpu_pm && kvm_has_waitpkg()) {
@@ -50,7 +74,17 @@ static bool kvm_cpu_realizefn(CPUState *cs, Error **errp)
                                                    MSR_IA32_UCODE_REV);
         }
     }
-    return host_cpu_realizefn(cs, errp);
+    ret = host_cpu_realizefn(cs, errp);
+    if (!ret) {
+        return ret;
+    }
+
+    if ((env->features[FEAT_8000_0001_EDX] & CPUID_EXT2_LM) &&
+        cpu->guest_phys_bits == -1) {
+        kvm_set_guest_phys_bits(cs);
+    }
+
+    return true;
 }
 
 static bool lmce_supported(void)