Changeset 988 in vbox

Timestamp:

Feb 19, 2007 6:19:14 PM (18 years ago)

Author:

vboxsync

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

18802

Message:

Fixed the real cause of the tripple fault.

Location:

trunk/src/VBox/VMM

Files:

• Makefile (modified) (1 diff)
• VMM.cpp (modified) (3 diffs)
• VMMGC/TRPMGCHandlers.cpp (modified) (3 diffs)
• VMMGC/VMMGC.cpp (modified) (4 diffs)
• VMMGC/VMMGCA.asm (modified) (1 diff)
• VMMInternal.h (modified) (2 diffs)

trunk/src/VBox/VMM/Makefile

@@ -237 +237 @@
         VMMAll/TRPMAll.cpp \
         VMMAll/VMAll.cpp \
+        VMMAll/VMMAll.cpp \
         PATM/VMMGC/CSAMGC.cpp \
         PATM/VMMAll/CSAMAll.cpp \

trunk/src/VBox/VMM/VMM.cpp

@@ -2595 +2595 @@
             fDump = true;
     }
-    else if (    u8Trap != 8 /* double fault doesn't dare setting TrapNo. */
+    else if (    rcExpect != VINF_SUCCESS
+             &&  u8Trap != 8 /* double fault doesn't dare set TrapNo. */
              &&  u8Trap != 3 /* guest only, we're not in guest. */
              &&  u8Trap != 1 /* guest only, we're not in guest. */
@@ -2615 +2616 @@
         }
     }
-    else
+    else if (rcExpect != VINF_SUCCESS)
     {
         if (CPUMGetHyperSS(pVM) == SELMGetHyperDS(pVM))
@@ -2693 +2694 @@
         vmmR3DoTrapTest(pVM, 0xe, 0, VERR_TRPM_DONT_PANIC,  0x00000000, "vmmGCTestTrap0e_FaultEIP", "#PF (NULL)");
         vmmR3DoTrapTest(pVM, 0xe, 1, VERR_TRPM_DONT_PANIC,  0x00000000, "vmmGCTestTrap0e_FaultEIP", "#PF (NULL) WP");
+        vmmR3DoTrapTest(pVM, 0xe, 2, VINF_SUCCESS,          0x00000000, NULL,                       "#PF w/Tmp Handler");
+        vmmR3DoTrapTest(pVM, 0xe, 4, VINF_SUCCESS,          0x00000000, NULL,                       "#PF w/Tmp Handler and bad fs");
 
         /*

trunk/src/VBox/VMM/VMMGC/TRPMGCHandlers.cpp

@@ -37 +37 @@
 #include "TRPMInternal.h"
 #include <VBox/vm.h>
+#include <VBox/param.h>
 
 #include <VBox/err.h>
@@ -978 +979 @@
     {
         /*
-         * Just zero the register in question.
-         * We're ASSUMING that esp points to it.
+         * Check that there is still some stack left, if not we'll flag 
+         * a guru meditation (the alternative is a triple fault).
          */
+        RTGCUINTPTR cbStackUsed = (RTGCUINTPTR)VMMGetStackGC(pVM) - pRegFrame->esp;
+        if (cbStackUsed > VMM_STACK_SIZE - _1K)
+        {
+            LogRel(("trpmGCTrapInGeneric: ran out of stack: esp=#x cbStackUsed=%#x\n", pRegFrame->esp, cbStackUsed));
+            return VERR_TRPM_DONT_PANIC;
+        }
+
+        /*
+         * Just zero the register containing the selector in question.
+         * We'll deal with the actual stale or troublesome selector value in 
+         * the outermost trap frame.
+         */
+        PCPUMCTXCORE pCoreCtx = (PCPUMCTXCORE)pRegFrame->esp;
         switch (uUser & TRPM_TRAP_IN_OP_MASK)
         {
             case TRPM_TRAP_IN_MOV_GS:
+                pRegFrame->eax = 0;
+                pRegFrame->gs = 0; /* prevent recursive trouble. */
+                break;
             case TRPM_TRAP_IN_MOV_FS:
-                *(PRTSEL)pRegFrame->esp = 0;
+                pRegFrame->eax = 0;
+                pRegFrame->fs = 0; /* prevent recursive trouble. */
                 return VINF_SUCCESS;
 
@@ -1014 +1032 @@
             case TRPM_TRAP_IN_MOV_DS:
             {
-                PCPUMCTXCORE pTempGuestCtx = (PCPUMCTXCORE) pEsp;
+                PCPUMCTXCORE pTempGuestCtx = (PCPUMCTXCORE)pEsp;
 
                 /* Just copy the whole thing; several selector registers, eip (etc) and eax are not yet in pRegFrame. */

trunk/src/VBox/VMM/VMMGC/VMMGC.cpp

@@ -26 +26 @@
 #define LOG_GROUP LOG_GROUP_VMM
 #include <VBox/vmm.h>
+#include <VBox/trpm.h>
 #include "VMMInternal.h"
 #include <VBox/vm.h>
@@ -47 +48 @@
 *******************************************************************************/
 static int vmmGCTest(PVM pVM, unsigned uOperation, unsigned uArg);
+static DECLCALLBACK(int) vmmGCTestTmpPFHandler(PVM pVM, PCPUMCTXCORE pRegFrame);
+static DECLCALLBACK(int) vmmGCTestTmpPFHandlerCorruptFS(PVM pVM, PCPUMCTXCORE pRegFrame);
 
 
@@ -264 +267 @@
             if (uArg <= 1)
                 rc = vmmGCTestTrap0e();
+            else if (uArg == 2 || uArg == 4)
+            {
+                /*
+                 * Test the use of a temporary #PF handler.
+                 */
+                rc = TRPMGCSetTempHandler(pVM, X86_XCPT_PF, uArg != 4 ? vmmGCTestTmpPFHandler : vmmGCTestTmpPFHandlerCorruptFS);
+                if (VBOX_SUCCESS(rc))
+                {
+                    rc = vmmGCTestTrap0e();
+
+                    /* in case it didn't fire. */
+                    int rc2 = TRPMGCSetTempHandler(pVM, X86_XCPT_PF, NULL);
+                    if (VBOX_FAILURE(rc2) && VBOX_SUCCESS(rc))
+                        rc = rc2;
+                }
+            }
             break;
         }
@@ -277 +296 @@
 }
 
+
+/**
+ * Temporary #PF trap handler for the #PF test case.
+ *
+ * @returns VBox status code (appropriate for GC return).
+ *          In this context VBOX_SUCCESS means to restart the instruction.
+ * @param   pVM         VM handle.
+ * @param   pRegFrame   Trap register frame.
+ */
+static DECLCALLBACK(int) vmmGCTestTmpPFHandler(PVM pVM, PCPUMCTXCORE pRegFrame)
+{
+    if (pRegFrame->eip == (uintptr_t)vmmGCTestTrap0e_FaultEIP)
+    {
+        pRegFrame->eip = (uintptr_t)vmmGCTestTrap0e_ResumeEIP;
+        return VINF_SUCCESS;
+    }
+    return VERR_INTERNAL_ERROR;
+}
+
+
+/**
+ * Temporary #PF trap handler for the #PF test case, this one messes up the fs selector.
+ *
+ * @returns VBox status code (appropriate for GC return).
+ *          In this context VBOX_SUCCESS means to restart the instruction.
+ * @param   pVM         VM handle.
+ * @param   pRegFrame   Trap register frame.
+ */
+static DECLCALLBACK(int) vmmGCTestTmpPFHandlerCorruptFS(PVM pVM, PCPUMCTXCORE pRegFrame)
+{
+    int rc = vmmGCTestTmpPFHandler(pVM, pRegFrame);
+    pRegFrame->fs = 0x30;
+    return rc;
+}
+

trunk/src/VBox/VMM/VMMGC/VMMGCA.asm

@@ -210 +210 @@
     mov     eax, 0ffffffffh
     ret
+
+EXPORTEDNAME vmmGCTestTrap0e_ResumeEIP
+    RestoreAll
+    xor     eax, eax
+    ret
 ENDPROC vmmGCTestTrap0e
 

trunk/src/VBox/VMM/VMMInternal.h

@@ -451 +451 @@
 VMMGCDECL(int) vmmGCLoggerFlush(PRTLOGGERGC pLogger);
 
-/** @name Trap testcases
+/** @name Trap testcases and related labels.
  * @{ */
 DECLASM(void) vmmGCEnableWP(void);
@@ -459 +459 @@
 DECLASM(int) vmmGCTestTrap0d(void);
 DECLASM(int) vmmGCTestTrap0e(void);
+DECLASM(int) vmmGCTestTrap0e_FaultEIP(void); /**< a label */
+DECLASM(int) vmmGCTestTrap0e_ResumeEIP(void); /**< a label */
 /** @} */