Changeset 87040 in vbox for trunk/src/VBox

Timestamp:

Dec 4, 2020 6:28:01 AM (4 years ago)

Author:

vboxsync

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

141724

Message:

VMM: Better fix for r141682 - Fix delivery of external interrupts when executing nested-guests. Fixes nested-guest SMP hangs described in bugref:9562#c18

Location:

trunk/src/VBox/VMM

Files:

• VMMAll/IEMAllCImplVmxInstr.cpp.h (modified) (2 diffs)
• VMMR0/HMVMXR0.cpp (modified) (2 diffs)
• VMMR3/EM.cpp (modified) (1 diff)
• VMMR3/TRPM.cpp (modified) (1 diff)

trunk/src/VBox/VMM/VMMAll/IEMAllCImplVmxInstr.cpp.h

@@ -3528 +3528 @@
              * If the interrupt is pending and we -do- need to acknowledge the interrupt
              * on VM-exit, postpone VM-exit till after the interrupt controller has been
-             * acknowledged that the interrupt has been consumed.
+             * acknowledged that the interrupt has been consumed. Callers would have to call
+             * us again after getting the vector (and ofc, with fIntPending with false).
              */
             return VINF_VMX_INTERCEPT_NOT_ACTIVE;
@@ -3536 +3537 @@
          * If the interrupt is no longer pending (i.e. it has been acknowledged) and the
          * "External interrupt exiting" and "Acknowledge interrupt on VM-exit" controls are
-         * all set, we cause the VM-exit now. We need to record the external interrupt that
-         * just occurred in the VM-exit interruption information field.
+         * all set, we need to record the vector of the external interrupt in the
+         * VM-exit interruption information field. Otherwise, mark this field as invalid.
          *
          * See Intel spec. 27.2.2 "Information for VM Exits Due to Vectored Events".
          */
+        uint32_t uExitIntInfo;
         if (pVmcs->u32ExitCtls & VMX_EXIT_CTLS_ACK_EXT_INT)
         {
-            bool const     fNmiUnblocking = pVCpu->cpum.GstCtx.hwvirt.vmx.fNmiUnblockingIret;
-            uint32_t const uExitIntInfo   = RT_BF_MAKE(VMX_BF_EXIT_INT_INFO_VECTOR,           uVector)
-                                          | RT_BF_MAKE(VMX_BF_EXIT_INT_INFO_TYPE,             VMX_EXIT_INT_INFO_TYPE_EXT_INT)
-                                          | RT_BF_MAKE(VMX_BF_EXIT_INT_INFO_NMI_UNBLOCK_IRET, fNmiUnblocking)
-                                          | RT_BF_MAKE(VMX_BF_EXIT_INT_INFO_VALID,            1);
-            iemVmxVmcsSetExitIntInfo(pVCpu, uExitIntInfo);
-            return iemVmxVmexit(pVCpu, VMX_EXIT_EXT_INT, 0 /* u64ExitQual */);
-        }
+            bool const fNmiUnblocking = pVCpu->cpum.GstCtx.hwvirt.vmx.fNmiUnblockingIret;
+            uExitIntInfo = RT_BF_MAKE(VMX_BF_EXIT_INT_INFO_VECTOR,           uVector)
+                         | RT_BF_MAKE(VMX_BF_EXIT_INT_INFO_TYPE,             VMX_EXIT_INT_INFO_TYPE_EXT_INT)
+                         | RT_BF_MAKE(VMX_BF_EXIT_INT_INFO_NMI_UNBLOCK_IRET, fNmiUnblocking)
+                         | RT_BF_MAKE(VMX_BF_EXIT_INT_INFO_VALID,            1);
+        }
+        else
+            uExitIntInfo = 0;
+        iemVmxVmcsSetExitIntInfo(pVCpu, uExitIntInfo);
+
+        /*
+         * Cause the VM-exit whether or not the vector has been stored
+         * in the VM-exit interruption-information field.
+         */
+        return iemVmxVmexit(pVCpu, VMX_EXIT_EXT_INT, 0 /* u64ExitQual */);
     }
 

trunk/src/VBox/VMM/VMMR0/HMVMXR0.cpp

@@ -8913 +8913 @@
 
             /*
-             * EFLAGS.IF does not control the blocking of external interrupts when
-             * "External interrupt exiting" set. Fixes nasty SMP hang while executing nested-guest
-             * VCPUs on spinlocks and aren't rescued by other VM-exits (like a preemption timer),
-             * see @bugref{9562#c18}.
+             * We must not check EFLAGS directly when executing a nested-guest, use
+             * CPUMIsGuestPhysIntrEnabled() instead as EFLAGS.IF does not control the blocking of
+             * external interrupts when "External interrupt exiting" is set. This fixes a nasty
+             * SMP hang while executing nested-guest VCPUs on spinlocks which aren't rescued by
+             * other VM-exits (like a preemption timer), see @bugref{9562#c18}.
              *
-             * See Intel spec. 25.4.1 "Event Blocking"
+             * See Intel spec. 25.4.1 "Event Blocking".
              */
+            if (CPUMIsGuestPhysIntrEnabled(pVCpu))
+            {
 #ifdef VBOX_WITH_NESTED_HWVIRT_VMX
-            if (    fIsNestedGuest
-                &&  CPUMIsGuestVmxPinCtlsSet(pCtx, VMX_PIN_CTLS_EXT_INT_EXIT)
-                && !CPUMIsGuestVmxExitCtlsSet(pCtx, VMX_EXIT_CTLS_ACK_EXT_INT))
-            {
-                VBOXSTRICTRC rcStrict = IEMExecVmxVmexitExtInt(pVCpu, 0 /* uVector */, true /* fIntPending */);
-                Assert(rcStrict != VINF_VMX_INTERCEPT_NOT_ACTIVE);
-                return rcStrict;
-            }
+                if (   fIsNestedGuest
+                    && CPUMIsGuestVmxPinCtlsSet(pCtx, VMX_PIN_CTLS_EXT_INT_EXIT))
+                {
+                    VBOXSTRICTRC rcStrict = IEMExecVmxVmexitExtInt(pVCpu, 0 /* uVector */, true /* fIntPending */);
+                    Assert(rcStrict != VINF_VMX_INTERCEPT_NOT_ACTIVE);
+                    return rcStrict;
+                }
 #endif
-            if (pCtx->eflags.u32 & X86_EFL_IF)
-            {
                 uint8_t u8Interrupt;
                 rc = PDMGetInterrupt(pVCpu, &u8Interrupt);
@@ -8938 +8938 @@
 #ifdef VBOX_WITH_NESTED_HWVIRT_VMX
                     if (   fIsNestedGuest
-                        && CPUMIsGuestVmxPinCtlsSet(pCtx, VMX_PIN_CTLS_EXT_INT_EXIT)
-                        && CPUMIsGuestVmxExitCtlsSet(pCtx, VMX_EXIT_CTLS_ACK_EXT_INT))
+                        && CPUMIsGuestVmxPinCtlsSet(pCtx, VMX_PIN_CTLS_EXT_INT_EXIT))
                     {
                         VBOXSTRICTRC rcStrict = IEMExecVmxVmexitExtInt(pVCpu, u8Interrupt, false /* fIntPending */);

trunk/src/VBox/VMM/VMMR3/EM.cpp

@@ -1498 +1498 @@
 #ifdef VBOX_WITH_NESTED_HWVIRT_VMX
     /* Handle the "external interrupt" VM-exit intercept. */
-    if (    CPUMIsGuestVmxPinCtlsSet(&pVCpu->cpum.GstCtx, VMX_PIN_CTLS_EXT_INT_EXIT)
-        && !CPUMIsGuestVmxExitCtlsSet(&pVCpu->cpum.GstCtx, VMX_EXIT_CTLS_ACK_EXT_INT))
+    if (CPUMIsGuestVmxPinCtlsSet(&pVCpu->cpum.GstCtx, VMX_PIN_CTLS_EXT_INT_EXIT))
     {
         VBOXSTRICTRC rcStrict = IEMExecVmxVmexitExtInt(pVCpu, 0 /* uVector */, true /* fIntPending */);

trunk/src/VBox/VMM/VMMR3/TRPM.cpp

@@ -379 +379 @@
         if (   CPUMIsGuestInVmxNonRootMode(pCtx)
             && CPUMIsGuestVmxInterceptEvents(pCtx)
-            && CPUMIsGuestVmxPinCtlsSet(pCtx, VMX_PIN_CTLS_EXT_INT_EXIT)
-            && CPUMIsGuestVmxExitCtlsSet(pCtx, VMX_EXIT_CTLS_ACK_EXT_INT))
+            && CPUMIsGuestVmxPinCtlsSet(pCtx, VMX_PIN_CTLS_EXT_INT_EXIT))
         {
             VBOXSTRICTRC rcStrict = IEMExecVmxVmexitExtInt(pVCpu, u8Interrupt, false /* fIntPending */);