WHPX workaround bug in OSVW handling

Adds a workaround to an incorrect value setting CPUID Fn8000_0001_ECX[bit 9 OSVW] = 1. This can cause a guest linux kernel to panic when an issue to rdmsr C001_0140h returns 0. Disabling this feature correctly allows the guest to boot without accessing the osv workarounds. Signed-off-by: Justin Terry (VM) <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
dreddy · Jun 28, 2018 · e1753a7 · e1753a7
1 parent e7d9982
commit e1753a7
Showing 1 changed file with 12 additions and 1 deletion.
diff --git a/target/i386/whpx-all.c b/target/i386/whpx-all.c
@@ -961,6 +961,16 @@ static int whpx_vcpu_run(CPUState *cpu)
                     vcpu->exit_ctx.CpuidAccess.DefaultResultRcx |
                     CPUID_EXT_HYPERVISOR;
 
+                rdx = vcpu->exit_ctx.CpuidAccess.DefaultResultRdx;
+                rbx = vcpu->exit_ctx.CpuidAccess.DefaultResultRbx;
+                break;
+            case 0x80000001:
+                rax = vcpu->exit_ctx.CpuidAccess.DefaultResultRax;
+                /* Remove any support of OSVW */
+                rcx =
+                    vcpu->exit_ctx.CpuidAccess.DefaultResultRcx &
+                    ~CPUID_EXT3_OSVW;
+
                 rdx = vcpu->exit_ctx.CpuidAccess.DefaultResultRdx;
                 rbx = vcpu->exit_ctx.CpuidAccess.DefaultResultRbx;
                 break;
@@ -1382,12 +1392,13 @@ static int whpx_accel_init(MachineState *ms)
         goto error;
     }
 
-    UINT32 cpuidExitList[] = {1};
+    UINT32 cpuidExitList[] = {1, 0x80000001};
     hr = whp_dispatch.WHvSetPartitionProperty(
         whpx->partition,
         WHvPartitionPropertyCodeCpuidExitList,
         cpuidExitList,
         RTL_NUMBER_OF(cpuidExitList) * sizeof(UINT32));
+
     if (FAILED(hr)) {
         error_report("WHPX: Failed to set partition CpuidExitList hr=%08lx",
                      hr);