Changeset 48267 in vbox for trunk/src/VBox/HostDrivers/Support

Timestamp:

Sep 4, 2013 2:06:50 PM (12 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

88682

Message:

VMM: Allow VT-x to be used in SMX mode, more granular error checking.

File:

• trunk/src/VBox/HostDrivers/Support/SUPDrv.c (modified) (4 diffs)

trunk/src/VBox/HostDrivers/Support/SUPDrv.c

@@ -3394 +3394 @@
         uint32_t fFeaturesECX, fFeaturesEDX, uDummy;
         uint32_t uMaxId, uVendorEBX, uVendorECX, uVendorEDX;
-        uint64_t u64Value;
+        uint64_t u64FeatMsr;
 
         ASMCpuId(0, &uMaxId, &uVendorEBX, &uVendorECX, &uVendorEDX);
@@ -3409 +3409 @@
                )
             {
+                bool fInSmxMode;
+                bool fMsrLocked;
+                bool fSmxVmxAllowed;
+                bool fVmxAllowed;
+
                 /*
-                 * Both the LOCK and VMXON bit must be set; otherwise VMXON will generate a #GP.
-                 * Once the lock bit is set, this MSR can no longer be modified.
+                 * We require the lock bit and the appropriate VMXON bit to be set otherwise VMXON will generate a #GP
+                 * This is a simplified check (assumes BIOS does it job and properly locks the control bit). For the more
+                 * extensive procedure see hmR0InitIntelCpu().
                  */
-                u64Value = ASMRdMsr(MSR_IA32_FEATURE_CONTROL);
-                if (      (u64Value & (MSR_IA32_FEATURE_CONTROL_VMXON | MSR_IA32_FEATURE_CONTROL_LOCK))
-                       ==             (MSR_IA32_FEATURE_CONTROL_VMXON | MSR_IA32_FEATURE_CONTROL_LOCK) /* enabled and locked */
-                    || !(u64Value & MSR_IA32_FEATURE_CONTROL_LOCK) /* not enabled, but not locked either */
-                   )
+                u64FeatMsr     = ASMRdMsr(MSR_IA32_FEATURE_CONTROL);
+                fInSmxMode     = !!(ASMGetCR4() & X86_CR4_SMXE);
+                fMsrLocked     = !!(u64FeatMsr & MSR_IA32_FEATURE_CONTROL_LOCK);
+                fSmxVmxAllowed = fMsrLocked && !!(u64FeatMsr & MSR_IA32_FEATURE_CONTROL_SMX_VMXON);
+                fVmxAllowed    = fMsrLocked && !!(u64FeatMsr & MSR_IA32_FEATURE_CONTROL_VMXON);
+                if (   (fInSmxMode && fSmxVmxAllowed)
+                    || fVmxAllowed)
                 {
                     VMX_CAPABILITY vtCaps;
@@ -3432 +3440 @@
                     return VINF_SUCCESS;
                 }
-                return VERR_VMX_MSR_LOCKED_OR_DISABLED;
+                return fInSmxMode ? VERR_VMX_MSR_SMX_VMXON_DISABLED : VERR_VMX_MSR_VMXON_DISABLED;
             }
             return VERR_VMX_NO_VMX;
@@ -3451 +3459 @@
             {
                 /* Check if SVM is disabled */
-                u64Value = ASMRdMsr(MSR_K8_VM_CR);
-                if (!(u64Value & MSR_K8_VM_CR_SVM_DISABLE))
+                u64FeatMsr = ASMRdMsr(MSR_K8_VM_CR);
+                if (!(u64FeatMsr & MSR_K8_VM_CR_SVM_DISABLE))
                 {
                     uint32_t fSvmFeatures;