Changeset 9720 in vbox

Timestamp:

Jun 16, 2008 1:12:04 PM (17 years ago)

Author:

vboxsync

Message:

Emulate rdmsr & wrmsr.
Note that Intel mentions a (slightly different) REX.W version of RDMSR.

Location:

trunk/src/VBox/VMM

Files:

• VMMAll/EMAll.cpp (modified) (2 diffs)
• VMMR0/HWSVMR0.cpp (modified) (1 diff)
• VMMR0/HWVMXR0.cpp (modified) (1 diff)

trunk/src/VBox/VMM/VMMAll/EMAll.cpp

@@ -2144 +2144 @@
     int      rc;
 
-    /* Note: works the same in 32 and 64 bits modes. */
+    /** @todo According to the Intel manuals, there's a REX version of RDMSR that is slightly different.
+     *  That version clears the high dwords of both RDX & RAX */
     rc = CPUMQueryGuestCtxPtr(pVM, &pCtx);
     AssertRC(rc);
@@ -2228 +2229 @@
 static int emInterpretRdmsr(PVM pVM, PDISCPUSTATE pCpu, PCPUMCTXCORE pRegFrame, RTGCPTR pvFault, uint32_t *pcbSize)
 {
+    Assert(!(pCpu->prefix & PREFIX_REX));
     return EMInterpretRdmsr(pVM, pRegFrame);
 }

trunk/src/VBox/VMM/VMMR0/HWSVMR0.cpp

@@ -1714 +1714 @@
     /* Emulate in ring 3. */
     case SVM_EXIT_MSR:
-        /* Note: If we decide to emulate them here, then we must sync the MSRs that could have been changed (sysenter, fs/gs base)!!! */
-        rc = VERR_EM_INTERPRETER;
+    {
+        uint32_t cbSize;
+
+        /* Note: the intel manual claims there's a REX version of RDMSR that's slightly different, so we play safe by completely disassembling the instruction. */
+        Log(("SVM: %s\n", (pVMCB->ctrl.u64ExitInfo1 == 0) ? "rdmsr" : "wrmsr"));
+        rc = EMInterpretInstruction(pVM, CPUMCTX2CORE(pCtx), 0, &cbSize);
+        if (rc == VINF_SUCCESS)
+        {
+            /* EIP has been updated already. */
+
+            /* Only resume if successful. */
+            STAM_PROFILE_ADV_STOP(&pVM->hwaccm.s.StatExit, x);
+            goto ResumeExecution;
+        }
+        AssertMsg(rc == VERR_EM_INTERPRETER, ("EMU: %s failed with %Vrc\n", (pVMCB->ctrl.u64ExitInfo1 == 0) ? "rdmsr" : "wrmsr", rc));
         break;
+    }
 
     case SVM_EXIT_MONITOR:

trunk/src/VBox/VMM/VMMR0/HWVMXR0.cpp

@@ -1699 +1699 @@
     }
 
+    case VMX_EXIT_RDMSR:                /* 31 RDMSR. Guest software attempted to execute RDMSR. */
+    case VMX_EXIT_WRMSR:                /* 32 WRMSR. Guest software attempted to execute WRMSR. */
+    {
+        uint32_t cbSize;
+
+        /* Note: the intel manual claims there's a REX version of RDMSR that's slightly different, so we play safe by completely disassembling the instruction. */
+        Log2(("VMX: %s\n", (exitReason == VMX_EXIT_RDMSR) ? "rdmsr" : "wrmsr"));
+        rc = EMInterpretInstruction(pVM, CPUMCTX2CORE(pCtx), 0, &cbSize);
+        if (rc == VINF_SUCCESS)
+        {
+            /* EIP has been updated already. */
+
+            /* Only resume if successful. */
+            STAM_PROFILE_ADV_STOP(&pVM->hwaccm.s.StatExit, x);
+            goto ResumeExecution;
+        }
+        AssertMsg(rc == VERR_EM_INTERPRETER, ("EMU: %s failed with %Vrc\n", (exitReason == VMX_EXIT_RDMSR) ? "rdmsr" : "wrmsr", rc));
+        break;
+    }
+
     case VMX_EXIT_CRX_MOVE:             /* 28 Control-register accesses. */
     {