Changeset 4970 in vbox

Timestamp:

Sep 21, 2007 6:27:48 PM (17 years ago)

Author:

vboxsync

Message:

r=bird

Location:

trunk

Files:

• include/VBox/vmm.h (modified) (1 diff)
• src/VBox/VMM/VMMR0/VMMR0.cpp (modified) (5 diffs)

trunk/include/VBox/vmm.h

@@ -421 +421 @@
  * @param   pVM             The VM to operate on.
  * @param   enmOperation    Which operation to execute.
- * @remarks Assume called with interrupts disabled.
+ * @remarks Assume called with interrupts _enabled_.
  */
 VMMR0DECL(int) VMMR0EntryFast(PVM pVM, VMMR0OPERATION enmOperation);

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

@@ -558 +558 @@
         /*
          * Switch to GC and run guest raw mode code.
+         * Disable interrupts before doing the world switch.
          */
         case VMMR0_DO_RAW_RUN:
         {
-            /* We must disable interrupts here */
-            RTCCUINTREG uFlags = ASMIntDisableFlags();
-
             /* Safety precaution as hwaccm disables the switcher. */
             if (RT_LIKELY(!pVM->vmm.s.fSwitcherDisabled))
             {
+                RTCCUINTREG uFlags = ASMIntDisableFlags();
+
                 int rc = pVM->vmm.s.pfnR0HostToGuest(pVM);
                 pVM->vmm.s.iLastGCRc = rc;
@@ -574 +574 @@
                     TRPMR0DispatchHostInterrupt(pVM);
 
+                ASMSetFlags(uFlags);
+
 #ifdef VBOX_WITH_STATISTICS
                 STAM_COUNTER_INC(&pVM->vmm.s.StatRunGC);
                 vmmR0RecordRC(pVM, rc);
 #endif
-                ASMSetFlags(uFlags);
                 return rc;
             }
-            ASMSetFlags(uFlags);
 
             Assert(!pVM->vmm.s.fSwitcherDisabled);
@@ -589 +589 @@
         /*
          * Run guest code using the available hardware acceleration technology.
+         *
+         * Disable interrupts before we do anything interesting. On Windows we avoid
+         * this by having the support driver raise the IRQL before calling us, this way
+         * we hope to get away we page faults and later calling into the kernel.
          */
         case VMMR0_DO_HWACC_RUN:
@@ -594 +598 @@
             STAM_COUNTER_INC(&pVM->vmm.s.StatRunGC);
 
-#ifndef RT_OS_WINDOWS /* @todo check other hosts */
-            /* We must disable interrupts here */
+#ifndef RT_OS_WINDOWS /** @todo check other hosts */
             RTCCUINTREG uFlags = ASMIntDisableFlags();
 #endif
@@ -612 +615 @@
             }
             pVM->vmm.s.iLastGCRc = rc;
-#ifndef RT_OS_WINDOWS /* @todo check other hosts */
+#ifndef RT_OS_WINDOWS /** @todo check other hosts */
             ASMSetFlags(uFlags);
 #endif