Changeset 4598 in vbox

Timestamp:

Sep 7, 2007 9:23:11 AM (17 years ago)

Author:

vboxsync

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

24236

Message:

Only check for vmx root mode for 64 bits hosts.

File:

• trunk/src/VBox/VMM/VMMR0/HWACCMR0.cpp (modified) (3 diffs)

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

@@ -136 +136 @@
                         *(uint32_t *)pVM->hwaccm.s.vmx.pVMXON = MSR_IA32_VMX_BASIC_INFO_VMCS_ID(pVM->hwaccm.s.vmx.msr.vmx_basic_info);
 
+#if HC_ARCH_BITS == 64
                         /* Enter VMX Root Mode */
                         int rc = VMXEnable(pVM->hwaccm.s.vmx.pVMXONPhys);
@@ -141 +142 @@
                         {
                             /* 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
-                             * (b) turning off paging causes a #GP
+                             * (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.
@@ -149 +150 @@
                         }
                         VMXDisable();
+#endif
                     }
                 }