Changeset 8553 in vbox for trunk/src

Timestamp:

May 5, 2008 8:01:48 AM (17 years ago)

Author:

vboxsync

Message:

Moved VMX root mode check around.

File:

• trunk/src/VBox/VMM/VMMR0/HWACCMR0.cpp (modified) (2 diffs)

trunk/src/VBox/VMM/VMMR0/HWACCMR0.cpp

@@ -165 +165 @@
 
                 HWACCMR0Globals.vmx.msr.feature_ctrl = ASMRdMsr(MSR_IA32_FEATURE_CONTROL);
-                HWACCMR0Globals.vmx.hostCR4          = ASMGetCR4();
-
-#if HC_ARCH_BITS == 64
-                RTR0MEMOBJ pScatchMemObj;
-                void      *pvScatchPage;
-                RTHCPHYS   pScatchPagePhys;
-
-                rc = RTR0MemObjAllocCont(&pScatchMemObj, 1 << PAGE_SHIFT, true /* executable R0 mapping */);
-                if (RT_FAILURE(rc))
-                    return rc;
-
-                pvScatchPage    = RTR0MemObjAddress(pScatchMemObj);
-                pScatchPagePhys = RTR0MemObjGetPagePhysAddr(pScatchMemObj, 0);
-                memset(pvScatchPage, 0, PAGE_SIZE);
-
-                /* Set revision dword at the beginning of the structure. */
-                *(uint32_t *)pvScatchPage = MSR_IA32_VMX_BASIC_INFO_VMCS_ID(HWACCMR0Globals.vmx.msr.vmx_basic_info);
-
-                /* Make sure we don't get rescheduled to another cpu during this probe. */
-                RTCCUINTREG fFlags = ASMIntDisableFlags();
-
-                /*
-                 * Check CR4.VMXE
-                 */
-                if (!(HWACCMR0Globals.vmx.hostCR4 & X86_CR4_VMXE))
-                {
-                    /* In theory this bit could be cleared behind our back. Which would cause #UD faults when we
-                     * try to execute the VMX instructions...
-                     */
-                    ASMSetCR4(HWACCMR0Globals.vmx.hostCR4 | X86_CR4_VMXE);
-                }
-
-                /* Enter VMX Root Mode */
-                rc = VMXEnable(pScatchPagePhys);
-                if (VBOX_FAILURE(rc))
-                {
-                    /* KVM leaves the CPU in VMX root mode. Not only is this not allowed, it will crash the host when we enter raw mode, because
-                     * (a) clearing X86_CR4_VMXE in CR4 causes a #GP    (we no longer modify this bit)
-                     * (b) turning off paging causes a #GP              (unavoidable when switching from long to 32 bits mode)
-                     *
-                     * They should fix their code, but until they do we simply refuse to run.
-                     */
-                    HWACCMR0Globals.lLastError = VERR_VMX_IN_VMX_ROOT_MODE;
-                    HWACCMR0Globals.vmx.fSupported = false;
-                }
-                else
-                    VMXDisable();
-
-                /* Restore CR4 again; don't leave the X86_CR4_VMXE flag set if it wasn't so before (some software could incorrectly think it's in VMX mode) */
-                ASMSetCR4(HWACCMR0Globals.vmx.hostCR4);
-                ASMSetFlags(fFlags);
-
-                RTR0MemObjFree(pScatchMemObj, false);
-                if (VBOX_FAILURE(HWACCMR0Globals.lLastError))
-                    return HWACCMR0Globals.lLastError ;
-#endif
 
                 /* We need to check if VT-x has been properly initialized on all CPUs. Some BIOSes do a lousy job. */
@@ -250 +194 @@
                         HWACCMR0Globals.vmx.msr.vmx_cr4_fixed1  = ASMRdMsr(MSR_IA32_VMX_CR4_FIXED1);
                         HWACCMR0Globals.vmx.msr.vmx_vmcs_enum   = ASMRdMsr(MSR_IA32_VMX_VMCS_ENUM);
+                        HWACCMR0Globals.vmx.hostCR4             = ASMGetCR4();
+
+#if HC_ARCH_BITS == 64
+                        RTR0MEMOBJ pScatchMemObj;
+                        void      *pvScatchPage;
+                        RTHCPHYS   pScatchPagePhys;
+
+                        rc = RTR0MemObjAllocCont(&pScatchMemObj, 1 << PAGE_SHIFT, true /* executable R0 mapping */);
+                        if (RT_FAILURE(rc))
+                            return rc;
+
+                        pvScatchPage    = RTR0MemObjAddress(pScatchMemObj);
+                        pScatchPagePhys = RTR0MemObjGetPagePhysAddr(pScatchMemObj, 0);
+                        memset(pvScatchPage, 0, PAGE_SIZE);
+
+                        /* Set revision dword at the beginning of the structure. */
+                        *(uint32_t *)pvScatchPage = MSR_IA32_VMX_BASIC_INFO_VMCS_ID(HWACCMR0Globals.vmx.msr.vmx_basic_info);
+
+                        /* Make sure we don't get rescheduled to another cpu during this probe. */
+                        RTCCUINTREG fFlags = ASMIntDisableFlags();
+
+                        /*
+                         * Check CR4.VMXE
+                         */
+                        if (!(HWACCMR0Globals.vmx.hostCR4 & X86_CR4_VMXE))
+                        {
+                            /* In theory this bit could be cleared behind our back. Which would cause #UD faults when we
+                             * try to execute the VMX instructions...
+                             */
+                            ASMSetCR4(HWACCMR0Globals.vmx.hostCR4 | X86_CR4_VMXE);
+                        }
+
+                        /* Enter VMX Root Mode */
+                        rc = VMXEnable(pScatchPagePhys);
+                        if (VBOX_FAILURE(rc))
+                        {
+                            /* KVM leaves the CPU in VMX root mode. Not only is this not allowed, it will crash the host when we enter raw mode, because
+                             * (a) clearing X86_CR4_VMXE in CR4 causes a #GP    (we no longer modify this bit)
+                             * (b) turning off paging causes a #GP              (unavoidable when switching from long to 32 bits mode)
+                             *
+                             * They should fix their code, but until they do we simply refuse to run.
+                             */
+                            HWACCMR0Globals.lLastError = VERR_VMX_IN_VMX_ROOT_MODE;
+                            HWACCMR0Globals.vmx.fSupported = false;
+                        }
+                        else
+                            VMXDisable();
+
+                        /* Restore CR4 again; don't leave the X86_CR4_VMXE flag set if it wasn't so before (some software could incorrectly think it's in VMX mode) */
+                        ASMSetCR4(HWACCMR0Globals.vmx.hostCR4);
+                        ASMSetFlags(fFlags);
+
+                        RTR0MemObjFree(pScatchMemObj, false);
+                        if (VBOX_FAILURE(HWACCMR0Globals.lLastError))
+                            return HWACCMR0Globals.lLastError ;
+#endif
                     }
                     else