Changeset 105591 in vbox

Timestamp:

Aug 5, 2024 11:05:33 PM (7 months ago)

Author:

vboxsync

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

164270

Message:

VMM/IEM: Fixed a bug in iemTlbInvalidateLargePageWorkerInner for TLB sizes less than 512 for 2MB pages, and 1024 for 4MB pages. bugref:10727

Location:

trunk/src/VBox/VMM

Files:

• VMMAll/IEMAll.cpp (modified) (1 diff)
• VMMR3/IEMR3.cpp (modified) (1 diff)

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

@@ -781 +781 @@
     IEMTLBTRACE_LARGE_SCAN(pVCpu, a_fGlobal, a_fNonGlobal, a_fDataTlb);
 
-    /* Combine TAG values with the TLB revisions. */
+    /*
+     * Combine TAG values with the TLB revisions.
+     */
     RTGCPTR GCPtrTagGlob = a_fGlobal ? GCPtrTag | pTlb->uTlbRevisionGlobal : 0;
     if (a_fNonGlobal)
         GCPtrTag |= pTlb->uTlbRevision;
 
-    /* Set up the scan. */
-    bool const      fPartialScan = IEMTLB_ENTRY_COUNT >= (a_f2MbLargePage ? 512 : 1024);
-    uintptr_t       idxEven      = fPartialScan ? IEMTLB_TAG_TO_EVEN_INDEX(GCPtrTag) : 0;
+    /*
+     * Set up the scan.
+     *
+     * GCPtrTagMask: A 2MB page consists of 512 4K pages, so a 256 TLB will map
+     * offset zero and offset 1MB to the same slot pair.  Our GCPtrTag[Globl]
+     * values are for the range 0-1MB, or slots 0-256.  So, we construct a mask
+     * that fold large page offsets 1MB-2MB into the 0-1MB range.
+     *
+     * For our example with 2MB pages and a 256 entry TLB: 0xfffffffffffffeff
+     */
+    bool const      fPartialScan = IEMTLB_ENTRY_COUNT > (a_f2MbLargePage ? 512 : 1024);
+    uintptr_t       idxEven      = fPartialScan ? IEMTLB_TAG_TO_EVEN_INDEX(GCPtrTag)             : 0;
     uintptr_t const idxEvenEnd   = fPartialScan ? idxEven + ((a_f2MbLargePage ? 512 : 1024) * 2) : IEMTLB_ENTRY_COUNT * 2;
-    RTGCPTR const   GCPtrTagMask = fPartialScan
-                                 ? ~(RTGCPTR)0
-                                 :   ~(RTGCPTR)GUEST_PAGE_OFFSET_MASK
-                                   & ~(RTGCPTR)(   (RT_BIT_64(RT_MAX(  (a_f2MbLargePage ? 9 : 10)
-                                                                     - IEMTLB_ENTRY_COUNT_AS_POWER_OF_TWO, 0)) - 1U)
-                                                << IEMTLB_ENTRY_COUNT_AS_POWER_OF_TWO);
+    RTGCPTR const   GCPtrTagMask = fPartialScan ? ~(RTGCPTR)0
+                                 : ~(RTGCPTR)(  (RT_BIT_32(a_f2MbLargePage ? 9 : 10) - 1U)
+                                              & ~(uint32_t)(RT_BIT_32(IEMTLB_ENTRY_COUNT_AS_POWER_OF_TWO) - 1U));
+IEMTLBTRACE_USER3(pVCpu, GCPtrTagMask, GCPtrTag, RT_MAKE_U32(idxEven, idxEvenEnd), a_fDataTlb);
 
     /*

trunk/src/VBox/VMM/VMMR3/IEMR3.cpp

@@ -1257 +1257 @@
     uint64_t const    uTag  = IEMTLB_CALC_TAG_NO_REV(uAddress);
 #ifdef IEMTLB_TAG_TO_EVEN_INDEX
-    uint32_t const    uSlot = IEMTLB_TAG_TO_EVEN_INDEX(uAddress);
+    uint32_t const    uSlot = IEMTLB_TAG_TO_EVEN_INDEX(uTag);
 #else
-    uint32_t const    uSlot = IEMTLB_TAG_TO_INDEX(uAddress);
+    uint32_t const    uSlot = IEMTLB_TAG_TO_INDEX(uTag);
 #endif
     IEMTLBENTRY const TlbeL = pTlb->aEntries[uSlot];