Changeset 70782 in vbox for trunk/src/VBox/VMM/VMMAll

Timestamp:

Jan 29, 2018 7:46:15 AM (7 years ago)

Author:

vboxsync

Message:

VMM: Nested Hw.virt: Pick up the TSC offset from the original VMCB while applying the nested-guest TSC offset, rather
than the potentially modified VMCB.

Location:

trunk/src/VBox/VMM/VMMAll

Files:

• CPUMAllRegs.cpp (modified) (1 diff)
• HMSVMAll.cpp (modified) (1 diff)

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

@@ -2715 +2715 @@
 /**
  * Applies the TSC offset of a nested-guest if any and returns the new TSC
- * value for the guest.
+ * value for the guest (or nested-guest).
  *
  * @returns The TSC offset after applying any nested-guest TSC offset.
  * @param   pVCpu       The cross context virtual CPU structure of the calling EMT.
  * @param   uTicks      The guest TSC.
+ *
+ * @sa      HMSvmNstGstApplyTscOffset.
  */
 VMM_INT_DECL(uint64_t) CPUMApplyNestedGuestTscOffset(PVMCPU pVCpu, uint64_t uTicks)
 {
 #ifndef IN_RC
-    PCCPUMCTX pCtx  = &pVCpu->cpum.s.Guest;
+    PCCPUMCTX pCtx = &pVCpu->cpum.s.Guest;
     if (CPUMIsGuestInSvmNestedHwVirtMode(pCtx))
     {
-        PCSVMVMCB pVmcb = pCtx->hwvirt.svm.CTX_SUFF(pVmcb);
-        return uTicks + pVmcb->ctrl.u64TSCOffset;
+        if (!pCtx->hwvirt.svm.fHMCachedVmcb)
+        {
+            PCSVMVMCB pVmcb = pCtx->hwvirt.svm.CTX_SUFF(pVmcb);
+            return uTicks + pVmcb->ctrl.u64TSCOffset;
+        }
+        return HMSvmNstGstApplyTscOffset(pVCpu, uTicks);
     }
 

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

@@ -202 +202 @@
     return HMIsEnabled(pVM) && fVGif && fUseVGif;
 }
+
+
+/**
+ * Applies the TSC offset of an SVM nested-guest if any and returns the new TSC
+ * value for the nested-guest.
+ *
+ * @returns The TSC offset after applying any nested-guest TSC offset.
+ * @param   pVCpu       The cross context virtual CPU structure of the calling EMT.
+ * @param   uTicks      The guest TSC.
+ *
+ * @remarks This function looks at the VMCB cache rather than directly at the
+ *          nested-guest VMCB. The latter may have been modified for executing
+ *          using hardware-assisted SVM.
+ *
+ * @sa      CPUMApplyNestedGuestTscOffset.
+ */
+VMM_INT_DECL(uint64_t) HMSvmNstGstApplyTscOffset(PVMCPU pVCpu, uint64_t uTicks)
+{
+    PCCPUMCTX pCtx = &pVCpu->cpum.GstCtx;
+    Assert(CPUMIsGuestInSvmNestedHwVirtMode(pCtx));
+    Assert(pCtx->hwvirt.svm.fHMCachedVmcb);
+    NOREF(pCtx);
+    PCSVMNESTEDVMCBCACHE pVmcbNstGstCache = &pVCpu->hm.s.svm.NstGstVmcbCache;
+    return uTicks + pVmcbNstGstCache->u64TSCOffset;
+}
 #endif /* !IN_RC */