Changeset 41908 in vbox

Timestamp:

Jun 25, 2012 1:19:18 AM (13 years ago)

Author:

vboxsync

Message:

Check loaded selector register the GDT changes.

Location:

trunk

Files:

• include/VBox/vmm/cpumctx.h (modified) (2 diffs)
• src/VBox/VMM/VMMRC/SELMRC.cpp (modified) (2 diffs)

trunk/include/VBox/vmm/cpumctx.h

@@ -236 +236 @@
     /** @name General Register.
      * @note  These follow the encoding order (X86_GREG_XXX) and can be accessed as
-     *        an array starting a rax.
+     *        an array starting at rax.
      * @{ */
     union
@@ -304 +304 @@
     /** @name Segment registers.
      * @note These follow the encoding order (X86_SREG_XXX) and can be accessed as
-     *       an array starting a es.
+     *       an array starting at es.
      * @{  */
     CPUMSELREG          es;

trunk/src/VBox/VMM/VMMRC/SELMRC.cpp

@@ -132 +132 @@
     *pShadowDescr = Desc;
 
-    /* Check if we change the LDT selector */
+    /*
+     * Detect and mark stale registers.
+     */
+    PCPUMCTX    pCtx      = CPUMQueryGuestCtxPtr(pVCpu);
+    PCPUMSELREG paSRegCtx = &pCtx->es;
+    PCPUMSELREG paSRegFrm = &pRegFrame->es;
+    for (unsigned i = 0; i <= X86_SREG_GS; i++)
+        if (Sel == (paSRegFrm[i].Sel & X86_SEL_MASK))
+        {
+            /** @todo we clear the valid flag here, maybe we shouldn't... but that would
+             *        require implementing handling of stale registers in raw-mode.
+             *        Tricky, at least for SS and CS. */
+            paSRegFrm[i].fFlags = CPUMSELREG_FLAGS_STALE;
+            paSRegCtx[i].fFlags = CPUMSELREG_FLAGS_STALE;
+        }
+
+    /*
+     * Check if we change the LDT selector.
+     */
     if (Sel == CPUMGetGuestLDTR(pVCpu)) /** @todo this isn't correct in two(+) ways! 1. It shouldn't be done until the LDTR is reloaded. 2. It caused the next instruction to be emulated.  */
     {
@@ -153 +171 @@
         Log(("GDT write to selector in SS register %04X\n", pRegFrame->ss.Sel));
 #endif
+
     return VINF_SUCCESS;
 }