Changeset 54650 in vbox for trunk/src/VBox/VMM/VMMR0

Timestamp:

Mar 5, 2015 1:42:10 PM (10 years ago)

Author:

vboxsync

Message:

SUPDrv/VMMR0: properly handle the CR4 shadow register on Linux >= 4.0

File:

• trunk/src/VBox/VMM/VMMR0/HMVMXR0.cpp (modified) (5 diffs)

trunk/src/VBox/VMM/VMMR0/HMVMXR0.cpp

@@ -773 +773 @@
 
     /* Enable the VMX bit in CR4 if necessary. */
-    RTCCUINTREG uCr4 = ASMGetCR4();
-    if (!(uCr4 & X86_CR4_VMXE))
-        ASMSetCR4(uCr4 | X86_CR4_VMXE);
+    RTCCUINTREG uOldCr4 = SUPR0ChangeCR4(X86_CR4_VMXE, ~0);
 
     /* Enter VMX root mode. */
     int rc = VMXEnable(HCPhysCpuPage);
-    if (RT_FAILURE(rc))
-        ASMSetCR4(uCr4);
+    if (   RT_FAILURE(rc)
+        && !(uOldCr4 & X86_CR4_VMXE))
+        SUPR0ChangeCR4(0, ~X86_CR4_VMXE);
 
     /* Restore interrupts. */
@@ -808 +807 @@
         /* Exit VMX root mode and clear the VMX bit in CR4. */
         VMXDisable();
-        ASMSetCR4(uHostCR4 & ~X86_CR4_VMXE);
+        SUPR0ChangeCR4(0, ~X86_CR4_VMXE);
         rc = VINF_SUCCESS;
     }
@@ -5216 +5215 @@
     VMXDisable();
 
-    ASMSetCR4(ASMGetCR4() & ~X86_CR4_VMXE);
+    SUPR0ChangeCR4(0, ~X86_CR4_VMXE);
 
     CPUMSetHyperESP(pVCpu, VMMGetStackRC(pVCpu));
@@ -5231 +5230 @@
     /** @todo replace with hmR0VmxEnterRootMode() and hmR0VmxLeaveRootMode(). */
     /* Make sure the VMX instructions don't cause #UD faults. */
-    ASMSetCR4(ASMGetCR4() | X86_CR4_VMXE);
+    SUPR0ChangeCR4(X86_CR4_VMXE, ~0);
 
     /* Re-enter VMX Root Mode */
@@ -5237 +5236 @@
     if (RT_FAILURE(rc2))
     {
-        ASMSetCR4(ASMGetCR4() & ~X86_CR4_VMXE);
+        SUPR0ChangeCR4(0, ~X86_CR4_VMXE);
         ASMSetFlags(uOldEflags);
         return rc2;