Adding upstream version 6.1.22-dfsg.upstream/6.1.22-dfsgupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 929 insertions, 0 deletions

diff --git a/src/VBox/VMM/VMMR3/PGMPool.cpp b/src/VBox/VMM/VMMR3/PGMPool.cpp
new file mode 100644
index 00000000..c4130849
--- /dev/null
+++ b/src/VBox/VMM/VMMR3/PGMPool.cpp
@@ -0,0 +1,929 @@
+/* $Id: PGMPool.cpp $ */
+/** @file
+ * PGM Shadow Page Pool.
+ */
+
+/*
+ * Copyright (C) 2006-2020 Oracle Corporation
+ *
+ * This file is part of VirtualBox Open Source Edition (OSE), as
+ * available from http://www.virtualbox.org. This file is free software;
+ * you can redistribute it and/or modify it under the terms of the GNU
+ * General Public License (GPL) as published by the Free Software
+ * Foundation, in version 2 as it comes in the "COPYING" file of the
+ * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+ * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+ */
+
+/** @page pg_pgm_pool       PGM Shadow Page Pool
+ *
+ * Motivations:
+ *      -# Relationship between shadow page tables and physical guest pages. This
+ *         should allow us to skip most of the global flushes now following access
+ *         handler changes. The main expense is flushing shadow pages.
+ *      -# Limit the pool size if necessary (default is kind of limitless).
+ *      -# Allocate shadow pages from RC. We use to only do this in SyncCR3.
+ *      -# Required for 64-bit guests.
+ *      -# Combining the PD cache and page pool in order to simplify caching.
+ *
+ *
+ * @section sec_pgm_pool_outline    Design Outline
+ *
+ * The shadow page pool tracks pages used for shadowing paging structures (i.e.
+ * page tables, page directory, page directory pointer table and page map
+ * level-4). Each page in the pool has an unique identifier. This identifier is
+ * used to link a guest physical page to a shadow PT. The identifier is a
+ * non-zero value and has a relativly low max value - say 14 bits. This makes it
+ * possible to fit it into the upper bits of the of the aHCPhys entries in the
+ * ram range.
+ *
+ * By restricting host physical memory to the first 48 bits (which is the
+ * announced physical memory range of the K8L chip (scheduled for 2008)), we
+ * can safely use the upper 16 bits for shadow page ID and reference counting.
+ *
+ * Update: The 48 bit assumption will be lifted with the new physical memory
+ * management (PGMPAGE), so we won't have any trouble when someone stuffs 2TB
+ * into a box in some years.
+ *
+ * Now, it's possible for a page to be aliased, i.e. mapped by more than one PT
+ * or PD. This is solved by creating a list of physical cross reference extents
+ * when ever this happens. Each node in the list (extent) is can contain 3 page
+ * pool indexes. The list it self is chained using indexes into the paPhysExt
+ * array.
+ *
+ *
+ * @section sec_pgm_pool_life       Life Cycle of a Shadow Page
+ *
+ * -# The SyncPT function requests a page from the pool.
+ *    The request includes the kind of page it is (PT/PD, PAE/legacy), the
+ *    address of the page it's shadowing, and more.
+ * -# The pool responds to the request by allocating a new page.
+ *    When the cache is enabled, it will first check if it's in the cache.
+ *    Should the pool be exhausted, one of two things can be done:
+ *      -# Flush the whole pool and current CR3.
+ *      -# Use the cache to find a page which can be flushed (~age).
+ * -# The SyncPT function will sync one or more pages and insert it into the
+ *    shadow PD.
+ * -# The SyncPage function may sync more pages on a later \#PFs.
+ * -# The page is freed / flushed in SyncCR3 (perhaps) and some other cases.
+ *    When caching is enabled, the page isn't flush but remains in the cache.
+ *
+ *
+ * @section sec_pgm_pool_monitoring Monitoring
+ *
+ * We always monitor PAGE_SIZE chunks of memory. When we've got multiple shadow
+ * pages for the same PAGE_SIZE of guest memory (PAE and mixed PD/PT) the pages
+ * sharing the monitor get linked using the iMonitoredNext/Prev. The head page
+ * is the pvUser to the access handlers.
+ *
+ *
+ * @section sec_pgm_pool_impl       Implementation
+ *
+ * The pool will take pages from the MM page pool. The tracking data
+ * (attributes, bitmaps and so on) are allocated from the hypervisor heap. The
+ * pool content can be accessed both by using the page id and the physical
+ * address (HC). The former is managed by means of an array, the latter by an
+ * offset based AVL tree.
+ *
+ * Flushing of a pool page means that we iterate the content (we know what kind
+ * it is) and updates the link information in the ram range.
+ *
+ * ...
+ */
+
+
+/*********************************************************************************************************************************
+*   Header Files                                                                                                                 *
+*********************************************************************************************************************************/
+#define LOG_GROUP LOG_GROUP_PGM_POOL
+#include <VBox/vmm/pgm.h>
+#include <VBox/vmm/mm.h>
+#include "PGMInternal.h"
+#include <VBox/vmm/vm.h>
+#include <VBox/vmm/uvm.h>
+#include "PGMInline.h"
+
+#include <VBox/log.h>
+#include <VBox/err.h>
+#include <iprt/asm.h>
+#include <iprt/string.h>
+#include <VBox/dbg.h>
+
+
+/*********************************************************************************************************************************
+*   Internal Functions                                                                                                           *
+*********************************************************************************************************************************/
+#ifdef VBOX_WITH_DEBUGGER
+static FNDBGCCMD pgmR3PoolCmdCheck;
+#endif
+
+#ifdef VBOX_WITH_DEBUGGER
+/** Command descriptors. */
+static const DBGCCMD    g_aCmds[] =
+{
+    /* pszCmd,  cArgsMin, cArgsMax, paArgDesc, cArgDescs, fFlags, pfnHandler          pszSyntax,  ....pszDescription */
+    { "pgmpoolcheck",  0, 0,        NULL,      0,         0,      pgmR3PoolCmdCheck,  "",         "Check the pgm pool pages." },
+};
+#endif
+
+/**
+ * Initializes the pool
+ *
+ * @returns VBox status code.
+ * @param   pVM     The cross context VM structure.
+ */
+int pgmR3PoolInit(PVM pVM)
+{
+    int rc;
+
+    AssertCompile(NIL_PGMPOOL_IDX == 0);
+    /* pPage->cLocked is an unsigned byte. */
+    AssertCompile(VMM_MAX_CPU_COUNT <= 255);
+
+    /*
+     * Query Pool config.
+     */
+    PCFGMNODE pCfg = CFGMR3GetChild(CFGMR3GetRoot(pVM), "/PGM/Pool");
+
+    /* Default pgm pool size is 1024 pages (4MB). */
+    uint16_t cMaxPages = 1024;
+
+    /* Adjust it up relative to the RAM size, using the nested paging formula. */
+    uint64_t cbRam;
+    rc = CFGMR3QueryU64Def(CFGMR3GetRoot(pVM), "RamSize", &cbRam, 0); AssertRCReturn(rc, rc);
+    uint64_t u64MaxPages = (cbRam >> 9)
+                         + (cbRam >> 18)
+                         + (cbRam >> 27)
+                         + 32 * PAGE_SIZE;
+    u64MaxPages >>= PAGE_SHIFT;
+    if (u64MaxPages > PGMPOOL_IDX_LAST)
+        cMaxPages = PGMPOOL_IDX_LAST;
+    else
+        cMaxPages = (uint16_t)u64MaxPages;
+
+    /** @cfgm{/PGM/Pool/MaxPages, uint16_t, \#pages, 16, 0x3fff, F(ram-size)}
+     * The max size of the shadow page pool in pages. The pool will grow dynamically
+     * up to this limit.
+     */
+    rc = CFGMR3QueryU16Def(pCfg, "MaxPages", &cMaxPages, cMaxPages);
+    AssertLogRelRCReturn(rc, rc);
+    AssertLogRelMsgReturn(cMaxPages <= PGMPOOL_IDX_LAST && cMaxPages >= RT_ALIGN(PGMPOOL_IDX_FIRST, 16),
+                          ("cMaxPages=%u (%#x)\n", cMaxPages, cMaxPages), VERR_INVALID_PARAMETER);
+    AssertCompile(RT_IS_POWER_OF_TWO(PGMPOOL_CFG_MAX_GROW));
+    if (cMaxPages < PGMPOOL_IDX_LAST)
+        cMaxPages = RT_ALIGN(cMaxPages, PGMPOOL_CFG_MAX_GROW / 2);
+    if (cMaxPages > PGMPOOL_IDX_LAST)
+        cMaxPages = PGMPOOL_IDX_LAST;
+    LogRel(("PGM: PGMPool: cMaxPages=%u (u64MaxPages=%llu)\n", cMaxPages, u64MaxPages));
+
+    /** @todo
+     * We need to be much more careful with our allocation strategy here.
+     * For nested paging we don't need pool user info nor extents at all, but
+     * we can't check for nested paging here (too early during init to get a
+     * confirmation it can be used).  The default for large memory configs is a
+     * bit large for shadow paging, so I've restricted the extent maximum to 8k
+     * (8k * 16 = 128k of hyper heap).
+     *
+     * Also when large page support is enabled, we typically don't need so much,
+     * although that depends on the availability of 2 MB chunks on the host.
+     */
+
+    /** @cfgm{/PGM/Pool/MaxUsers, uint16_t, \#users, MaxUsers, 32K, MaxPages*2}
+     * The max number of shadow page user tracking records. Each shadow page has
+     * zero of other shadow pages (or CR3s) that references it, or uses it if you
+     * like. The structures describing these relationships are allocated from a
+     * fixed sized pool. This configuration variable defines the pool size.
+     */
+    uint16_t cMaxUsers;
+    rc = CFGMR3QueryU16Def(pCfg, "MaxUsers", &cMaxUsers, cMaxPages * 2);
+    AssertLogRelRCReturn(rc, rc);
+    AssertLogRelMsgReturn(cMaxUsers >= cMaxPages && cMaxPages <= _32K,
+                          ("cMaxUsers=%u (%#x)\n", cMaxUsers, cMaxUsers), VERR_INVALID_PARAMETER);
+
+    /** @cfgm{/PGM/Pool/MaxPhysExts, uint16_t, \#extents, 16, MaxPages * 2, MIN(MaxPages*2\,8192)}
+     * The max number of extents for tracking aliased guest pages.
+     */
+    uint16_t cMaxPhysExts;
+    rc = CFGMR3QueryU16Def(pCfg, "MaxPhysExts", &cMaxPhysExts,
+                           RT_MIN(cMaxPages * 2, 8192 /* 8Ki max as this eat too much hyper heap */));
+    AssertLogRelRCReturn(rc, rc);
+    AssertLogRelMsgReturn(cMaxPhysExts >= 16 && cMaxPhysExts <= PGMPOOL_IDX_LAST,
+                          ("cMaxPhysExts=%u (%#x)\n", cMaxPhysExts, cMaxPhysExts), VERR_INVALID_PARAMETER);
+
+    /** @cfgm{/PGM/Pool/ChacheEnabled, bool, true}
+     * Enables or disabling caching of shadow pages. Caching means that we will try
+     * reuse shadow pages instead of recreating them everything SyncCR3, SyncPT or
+     * SyncPage requests one. When reusing a shadow page, we can save time
+     * reconstructing it and it's children.
+     */
+    bool fCacheEnabled;
+    rc = CFGMR3QueryBoolDef(pCfg, "CacheEnabled", &fCacheEnabled, true);
+    AssertLogRelRCReturn(rc, rc);
+
+    LogRel(("PGM: pgmR3PoolInit: cMaxPages=%#RX16 cMaxUsers=%#RX16 cMaxPhysExts=%#RX16 fCacheEnable=%RTbool\n",
+             cMaxPages, cMaxUsers, cMaxPhysExts, fCacheEnabled));
+
+    /*
+     * Allocate the data structures.
+     */
+    uint32_t cb = RT_UOFFSETOF_DYN(PGMPOOL, aPages[cMaxPages]);
+    cb += cMaxUsers * sizeof(PGMPOOLUSER);
+    cb += cMaxPhysExts * sizeof(PGMPOOLPHYSEXT);
+    PPGMPOOL pPool;
+    rc = MMR3HyperAllocOnceNoRel(pVM, cb, 0, MM_TAG_PGM_POOL, (void **)&pPool);
+    if (RT_FAILURE(rc))
+        return rc;
+    pVM->pgm.s.pPoolR3 = pPool;
+    pVM->pgm.s.pPoolR0 = MMHyperR3ToR0(pVM, pPool);
+
+    /*
+     * Initialize it.
+     */
+    pPool->pVMR3     = pVM;
+    pPool->pVMR0     = pVM->pVMR0ForCall;
+    pPool->cMaxPages = cMaxPages;
+    pPool->cCurPages = PGMPOOL_IDX_FIRST;
+    pPool->iUserFreeHead = 0;
+    pPool->cMaxUsers = cMaxUsers;
+    PPGMPOOLUSER paUsers = (PPGMPOOLUSER)&pPool->aPages[pPool->cMaxPages];
+    pPool->paUsersR3 = paUsers;
+    pPool->paUsersR0 = MMHyperR3ToR0(pVM, paUsers);
+    for (unsigned i = 0; i < cMaxUsers; i++)
+    {
+        paUsers[i].iNext = i + 1;
+        paUsers[i].iUser = NIL_PGMPOOL_IDX;
+        paUsers[i].iUserTable = 0xfffffffe;
+    }
+    paUsers[cMaxUsers - 1].iNext = NIL_PGMPOOL_USER_INDEX;
+    pPool->iPhysExtFreeHead = 0;
+    pPool->cMaxPhysExts = cMaxPhysExts;
+    PPGMPOOLPHYSEXT paPhysExts = (PPGMPOOLPHYSEXT)&paUsers[cMaxUsers];
+    pPool->paPhysExtsR3 = paPhysExts;
+    pPool->paPhysExtsR0 = MMHyperR3ToR0(pVM, paPhysExts);
+    for (unsigned i = 0; i < cMaxPhysExts; i++)
+    {
+        paPhysExts[i].iNext = i + 1;
+        paPhysExts[i].aidx[0] = NIL_PGMPOOL_IDX;
+        paPhysExts[i].apte[0] = NIL_PGMPOOL_PHYSEXT_IDX_PTE;
+        paPhysExts[i].aidx[1] = NIL_PGMPOOL_IDX;
+        paPhysExts[i].apte[1] = NIL_PGMPOOL_PHYSEXT_IDX_PTE;
+        paPhysExts[i].aidx[2] = NIL_PGMPOOL_IDX;
+        paPhysExts[i].apte[2] = NIL_PGMPOOL_PHYSEXT_IDX_PTE;
+    }
+    paPhysExts[cMaxPhysExts - 1].iNext = NIL_PGMPOOL_PHYSEXT_INDEX;
+    for (unsigned i = 0; i < RT_ELEMENTS(pPool->aiHash); i++)
+        pPool->aiHash[i] = NIL_PGMPOOL_IDX;
+    pPool->iAgeHead = NIL_PGMPOOL_IDX;
+    pPool->iAgeTail = NIL_PGMPOOL_IDX;
+    pPool->fCacheEnabled = fCacheEnabled;
+
+    pPool->hAccessHandlerType = NIL_PGMPHYSHANDLERTYPE;
+    rc = PGMR3HandlerPhysicalTypeRegister(pVM, PGMPHYSHANDLERKIND_WRITE,
+                                          pgmPoolAccessHandler,
+                                          NULL, "pgmPoolAccessHandler", "pgmRZPoolAccessPfHandler",
+                                          NULL, "pgmPoolAccessHandler", "pgmRZPoolAccessPfHandler",
+                                          "Guest Paging Access Handler",
+                                          &pPool->hAccessHandlerType);
+    AssertLogRelRCReturn(rc, rc);
+
+    pPool->HCPhysTree = 0;
+
+    /*
+     * The NIL entry.
+     */
+    Assert(NIL_PGMPOOL_IDX == 0);
+    pPool->aPages[NIL_PGMPOOL_IDX].enmKind          = PGMPOOLKIND_INVALID;
+    pPool->aPages[NIL_PGMPOOL_IDX].idx              = NIL_PGMPOOL_IDX;
+    pPool->aPages[NIL_PGMPOOL_IDX].Core.Key         = NIL_RTHCPHYS;
+    pPool->aPages[NIL_PGMPOOL_IDX].GCPhys           = NIL_RTGCPHYS;
+    pPool->aPages[NIL_PGMPOOL_IDX].iNext            = NIL_PGMPOOL_IDX;
+    /* pPool->aPages[NIL_PGMPOOL_IDX].cLocked          = INT32_MAX; - test this out... */
+    pPool->aPages[NIL_PGMPOOL_IDX].pvPageR3         = 0;
+    pPool->aPages[NIL_PGMPOOL_IDX].iUserHead        = NIL_PGMPOOL_USER_INDEX;
+    pPool->aPages[NIL_PGMPOOL_IDX].iModifiedNext    = NIL_PGMPOOL_IDX;
+    pPool->aPages[NIL_PGMPOOL_IDX].iModifiedPrev    = NIL_PGMPOOL_IDX;
+    pPool->aPages[NIL_PGMPOOL_IDX].iMonitoredNext   = NIL_PGMPOOL_IDX;
+    pPool->aPages[NIL_PGMPOOL_IDX].iMonitoredPrev   = NIL_PGMPOOL_IDX;
+    pPool->aPages[NIL_PGMPOOL_IDX].iAgeNext         = NIL_PGMPOOL_IDX;
+    pPool->aPages[NIL_PGMPOOL_IDX].iAgePrev         = NIL_PGMPOOL_IDX;
+
+    Assert(pPool->aPages[NIL_PGMPOOL_IDX].idx == NIL_PGMPOOL_IDX);
+    Assert(pPool->aPages[NIL_PGMPOOL_IDX].GCPhys == NIL_RTGCPHYS);
+    Assert(!pPool->aPages[NIL_PGMPOOL_IDX].fSeenNonGlobal);
+    Assert(!pPool->aPages[NIL_PGMPOOL_IDX].fMonitored);
+    Assert(!pPool->aPages[NIL_PGMPOOL_IDX].fCached);
+    Assert(!pPool->aPages[NIL_PGMPOOL_IDX].fZeroed);
+    Assert(!pPool->aPages[NIL_PGMPOOL_IDX].fReusedFlushPending);
+
+    /*
+     * Register statistics.
+     */
+    STAM_REL_REG(pVM, &pPool->StatGrow,                 STAMTYPE_PROFILE,   "/PGM/Pool/Grow",           STAMUNIT_TICKS, "Profiling PGMR0PoolGrow");
+#ifdef VBOX_WITH_STATISTICS
+    STAM_REG(pVM, &pPool->cCurPages,                    STAMTYPE_U16,       "/PGM/Pool/cCurPages",      STAMUNIT_PAGES,             "Current pool size.");
+    STAM_REG(pVM, &pPool->cMaxPages,                    STAMTYPE_U16,       "/PGM/Pool/cMaxPages",      STAMUNIT_PAGES,             "Max pool size.");
+    STAM_REG(pVM, &pPool->cUsedPages,                   STAMTYPE_U16,       "/PGM/Pool/cUsedPages",     STAMUNIT_PAGES,             "The number of pages currently in use.");
+    STAM_REG(pVM, &pPool->cUsedPagesHigh,               STAMTYPE_U16_RESET, "/PGM/Pool/cUsedPagesHigh", STAMUNIT_PAGES,             "The high watermark for cUsedPages.");
+    STAM_REG(pVM, &pPool->StatAlloc,                  STAMTYPE_PROFILE_ADV, "/PGM/Pool/Alloc",          STAMUNIT_TICKS_PER_CALL,    "Profiling of pgmPoolAlloc.");
+    STAM_REG(pVM, &pPool->StatClearAll,                 STAMTYPE_PROFILE,   "/PGM/Pool/ClearAll",       STAMUNIT_TICKS_PER_CALL,    "Profiling of pgmR3PoolClearAll.");
+    STAM_REG(pVM, &pPool->StatR3Reset,                  STAMTYPE_PROFILE,   "/PGM/Pool/R3Reset",        STAMUNIT_TICKS_PER_CALL,    "Profiling of pgmR3PoolReset.");
+    STAM_REG(pVM, &pPool->StatFlushPage,                STAMTYPE_PROFILE,   "/PGM/Pool/FlushPage",      STAMUNIT_TICKS_PER_CALL,    "Profiling of pgmPoolFlushPage.");
+    STAM_REG(pVM, &pPool->StatFree,                     STAMTYPE_PROFILE,   "/PGM/Pool/Free",           STAMUNIT_TICKS_PER_CALL,    "Profiling of pgmPoolFree.");
+    STAM_REG(pVM, &pPool->StatForceFlushPage,           STAMTYPE_COUNTER,   "/PGM/Pool/FlushForce",     STAMUNIT_OCCURENCES,        "Counting explicit flushes by PGMPoolFlushPage().");
+    STAM_REG(pVM, &pPool->StatForceFlushDirtyPage,      STAMTYPE_COUNTER,   "/PGM/Pool/FlushForceDirty",     STAMUNIT_OCCURENCES,   "Counting explicit flushes of dirty pages by PGMPoolFlushPage().");
+    STAM_REG(pVM, &pPool->StatForceFlushReused,         STAMTYPE_COUNTER,   "/PGM/Pool/FlushReused",    STAMUNIT_OCCURENCES,        "Counting flushes for reused pages.");
+    STAM_REG(pVM, &pPool->StatZeroPage,                 STAMTYPE_PROFILE,   "/PGM/Pool/ZeroPage",       STAMUNIT_TICKS_PER_CALL,    "Profiling time spent zeroing pages. Overlaps with Alloc.");
+    STAM_REG(pVM, &pPool->cMaxUsers,                    STAMTYPE_U16,       "/PGM/Pool/Track/cMaxUsers",            STAMUNIT_COUNT,      "Max user tracking records.");
+    STAM_REG(pVM, &pPool->cPresent,                     STAMTYPE_U32,       "/PGM/Pool/Track/cPresent",             STAMUNIT_COUNT,      "Number of present page table entries.");
+    STAM_REG(pVM, &pPool->StatTrackDeref,               STAMTYPE_PROFILE,   "/PGM/Pool/Track/Deref",                STAMUNIT_TICKS_PER_CALL, "Profiling of pgmPoolTrackDeref.");
+    STAM_REG(pVM, &pPool->StatTrackFlushGCPhysPT,       STAMTYPE_PROFILE,   "/PGM/Pool/Track/FlushGCPhysPT",        STAMUNIT_TICKS_PER_CALL, "Profiling of pgmPoolTrackFlushGCPhysPT.");
+    STAM_REG(pVM, &pPool->StatTrackFlushGCPhysPTs,      STAMTYPE_PROFILE,   "/PGM/Pool/Track/FlushGCPhysPTs",       STAMUNIT_TICKS_PER_CALL, "Profiling of pgmPoolTrackFlushGCPhysPTs.");
+    STAM_REG(pVM, &pPool->StatTrackFlushGCPhysPTsSlow,  STAMTYPE_PROFILE,   "/PGM/Pool/Track/FlushGCPhysPTsSlow",   STAMUNIT_TICKS_PER_CALL, "Profiling of pgmPoolTrackFlushGCPhysPTsSlow.");
+    STAM_REG(pVM, &pPool->StatTrackFlushEntry,          STAMTYPE_COUNTER,   "/PGM/Pool/Track/Entry/Flush",          STAMUNIT_COUNT,          "Nr of flushed entries.");
+    STAM_REG(pVM, &pPool->StatTrackFlushEntryKeep,      STAMTYPE_COUNTER,   "/PGM/Pool/Track/Entry/Update",         STAMUNIT_COUNT,          "Nr of updated entries.");
+    STAM_REG(pVM, &pPool->StatTrackFreeUpOneUser,       STAMTYPE_COUNTER,   "/PGM/Pool/Track/FreeUpOneUser",        STAMUNIT_TICKS_PER_CALL, "The number of times we were out of user tracking records.");
+    STAM_REG(pVM, &pPool->StatTrackDerefGCPhys,         STAMTYPE_PROFILE,   "/PGM/Pool/Track/DrefGCPhys",           STAMUNIT_TICKS_PER_CALL, "Profiling deref activity related tracking GC physical pages.");
+    STAM_REG(pVM, &pPool->StatTrackLinearRamSearches,   STAMTYPE_COUNTER,   "/PGM/Pool/Track/LinearRamSearches",    STAMUNIT_OCCURENCES, "The number of times we had to do linear ram searches.");
+    STAM_REG(pVM, &pPool->StamTrackPhysExtAllocFailures,STAMTYPE_COUNTER,   "/PGM/Pool/Track/PhysExtAllocFailures", STAMUNIT_OCCURENCES, "The number of failing pgmPoolTrackPhysExtAlloc calls.");
+
+    STAM_REG(pVM, &pPool->StatMonitorPfRZ,                STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/#PF",                 STAMUNIT_TICKS_PER_CALL, "Profiling the RC/R0 #PF access handler.");
+    STAM_REG(pVM, &pPool->StatMonitorPfRZEmulateInstr,    STAMTYPE_COUNTER, "/PGM/Pool/Monitor/RZ/#PF/EmulateInstr",    STAMUNIT_OCCURENCES,     "Times we've failed interpreting the instruction.");
+    STAM_REG(pVM, &pPool->StatMonitorPfRZFlushPage,       STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/#PF/FlushPage",       STAMUNIT_TICKS_PER_CALL, "Profiling the pgmPoolFlushPage calls made from the RC/R0 access handler.");
+    STAM_REG(pVM, &pPool->StatMonitorPfRZFlushReinit,     STAMTYPE_COUNTER, "/PGM/Pool/Monitor/RZ/#PF/FlushReinit",     STAMUNIT_OCCURENCES,     "Times we've detected a page table reinit.");
+    STAM_REG(pVM, &pPool->StatMonitorPfRZFlushModOverflow,STAMTYPE_COUNTER, "/PGM/Pool/Monitor/RZ/#PF/FlushOverflow",   STAMUNIT_OCCURENCES,     "Counting flushes for pages that are modified too often.");
+    STAM_REG(pVM, &pPool->StatMonitorPfRZFork,            STAMTYPE_COUNTER, "/PGM/Pool/Monitor/RZ/#PF/Fork",            STAMUNIT_OCCURENCES,     "Times we've detected fork().");
+    STAM_REG(pVM, &pPool->StatMonitorPfRZHandled,         STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/#PF/Handled",         STAMUNIT_TICKS_PER_CALL, "Profiling the RC/R0 #PF access we've handled (except REP STOSD).");
+    STAM_REG(pVM, &pPool->StatMonitorPfRZIntrFailPatch1,  STAMTYPE_COUNTER, "/PGM/Pool/Monitor/RZ/#PF/IntrFailPatch1",  STAMUNIT_OCCURENCES,     "Times we've failed interpreting a patch code instruction.");
+    STAM_REG(pVM, &pPool->StatMonitorPfRZIntrFailPatch2,  STAMTYPE_COUNTER, "/PGM/Pool/Monitor/RZ/#PF/IntrFailPatch2",  STAMUNIT_OCCURENCES,     "Times we've failed interpreting a patch code instruction during flushing.");
+    STAM_REG(pVM, &pPool->StatMonitorPfRZRepPrefix,       STAMTYPE_COUNTER, "/PGM/Pool/Monitor/RZ/#PF/RepPrefix",       STAMUNIT_OCCURENCES,     "The number of times we've seen rep prefixes we can't handle.");
+    STAM_REG(pVM, &pPool->StatMonitorPfRZRepStosd,        STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/#PF/RepStosd",        STAMUNIT_TICKS_PER_CALL, "Profiling the REP STOSD cases we've handled.");
+
+    STAM_REG(pVM, &pPool->StatMonitorRZ,                  STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM",                 STAMUNIT_TICKS_PER_CALL, "Profiling the regular access handler.");
+    STAM_REG(pVM, &pPool->StatMonitorRZFlushPage,         STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/FlushPage",       STAMUNIT_TICKS_PER_CALL, "Profiling the pgmPoolFlushPage calls made from the regular access handler.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZSizes[0],         STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Size01",          STAMUNIT_OCCURENCES,     "Number of 1 byte accesses.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZSizes[1],         STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Size02",          STAMUNIT_OCCURENCES,     "Number of 2 byte accesses.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZSizes[2],         STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Size03",          STAMUNIT_OCCURENCES,     "Number of 3 byte accesses.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZSizes[3],         STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Size04",          STAMUNIT_OCCURENCES,     "Number of 4 byte accesses.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZSizes[4],         STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Size05",          STAMUNIT_OCCURENCES,     "Number of 5 byte accesses.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZSizes[5],         STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Size06",          STAMUNIT_OCCURENCES,     "Number of 6 byte accesses.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZSizes[6],         STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Size07",          STAMUNIT_OCCURENCES,     "Number of 7 byte accesses.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZSizes[7],         STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Size08",          STAMUNIT_OCCURENCES,     "Number of 8 byte accesses.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZSizes[8],         STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Size09",          STAMUNIT_OCCURENCES,     "Number of 9 byte accesses.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZSizes[9],         STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Size0a",          STAMUNIT_OCCURENCES,     "Number of 10 byte accesses.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZSizes[10],        STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Size0b",          STAMUNIT_OCCURENCES,     "Number of 11 byte accesses.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZSizes[11],        STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Size0c",          STAMUNIT_OCCURENCES,     "Number of 12 byte accesses.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZSizes[12],        STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Size0d",          STAMUNIT_OCCURENCES,     "Number of 13 byte accesses.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZSizes[13],        STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Size0e",          STAMUNIT_OCCURENCES,     "Number of 14 byte accesses.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZSizes[14],        STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Size0f",          STAMUNIT_OCCURENCES,     "Number of 15 byte accesses.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZSizes[15],        STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Size10",          STAMUNIT_OCCURENCES,     "Number of 16 byte accesses.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZSizes[16],        STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Size11-2f",       STAMUNIT_OCCURENCES,     "Number of 17-31 byte accesses.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZSizes[17],        STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Size20-3f",       STAMUNIT_OCCURENCES,     "Number of 32-63 byte accesses.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZSizes[18],        STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Size40+",         STAMUNIT_OCCURENCES,     "Number of 64+ byte accesses.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZMisaligned[0],    STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Misaligned1",     STAMUNIT_OCCURENCES,     "Number of misaligned access with offset 1.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZMisaligned[1],    STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Misaligned2",     STAMUNIT_OCCURENCES,     "Number of misaligned access with offset 2.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZMisaligned[2],    STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Misaligned3",     STAMUNIT_OCCURENCES,     "Number of misaligned access with offset 3.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZMisaligned[3],    STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Misaligned4",     STAMUNIT_OCCURENCES,     "Number of misaligned access with offset 4.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZMisaligned[4],    STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Misaligned5",     STAMUNIT_OCCURENCES,     "Number of misaligned access with offset 5.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZMisaligned[5],    STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Misaligned6",     STAMUNIT_OCCURENCES,     "Number of misaligned access with offset 6.");
+    STAM_REG(pVM, &pPool->aStatMonitorRZMisaligned[6],    STAMTYPE_PROFILE, "/PGM/Pool/Monitor/RZ/IEM/Misaligned7",     STAMUNIT_OCCURENCES,     "Number of misaligned access with offset 7.");
+
+    STAM_REG(pVM, &pPool->StatMonitorRZFaultPT,           STAMTYPE_COUNTER, "/PGM/Pool/Monitor/RZ/Fault/PT",            STAMUNIT_OCCURENCES,     "Nr of handled PT faults.");
+    STAM_REG(pVM, &pPool->StatMonitorRZFaultPD,           STAMTYPE_COUNTER, "/PGM/Pool/Monitor/RZ/Fault/PD",            STAMUNIT_OCCURENCES,     "Nr of handled PD faults.");
+    STAM_REG(pVM, &pPool->StatMonitorRZFaultPDPT,         STAMTYPE_COUNTER, "/PGM/Pool/Monitor/RZ/Fault/PDPT",          STAMUNIT_OCCURENCES,     "Nr of handled PDPT faults.");
+    STAM_REG(pVM, &pPool->StatMonitorRZFaultPML4,         STAMTYPE_COUNTER, "/PGM/Pool/Monitor/RZ/Fault/PML4",          STAMUNIT_OCCURENCES,     "Nr of handled PML4 faults.");
+
+    STAM_REG(pVM, &pPool->StatMonitorR3,                  STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3",                     STAMUNIT_TICKS_PER_CALL, "Profiling the R3 access handler.");
+    STAM_REG(pVM, &pPool->StatMonitorR3FlushPage,         STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/FlushPage",           STAMUNIT_TICKS_PER_CALL, "Profiling the pgmPoolFlushPage calls made from the R3 access handler.");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Sizes[0],         STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Size01",              STAMUNIT_OCCURENCES,     "Number of 1 byte accesses (R3).");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Sizes[1],         STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Size02",              STAMUNIT_OCCURENCES,     "Number of 2 byte accesses (R3).");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Sizes[2],         STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Size03",              STAMUNIT_OCCURENCES,     "Number of 3 byte accesses (R3).");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Sizes[3],         STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Size04",              STAMUNIT_OCCURENCES,     "Number of 4 byte accesses (R3).");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Sizes[4],         STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Size05",              STAMUNIT_OCCURENCES,     "Number of 5 byte accesses (R3).");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Sizes[5],         STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Size06",              STAMUNIT_OCCURENCES,     "Number of 6 byte accesses (R3).");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Sizes[6],         STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Size07",              STAMUNIT_OCCURENCES,     "Number of 7 byte accesses (R3).");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Sizes[7],         STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Size08",              STAMUNIT_OCCURENCES,     "Number of 8 byte accesses (R3).");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Sizes[8],         STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Size09",              STAMUNIT_OCCURENCES,     "Number of 9 byte accesses (R3).");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Sizes[9],         STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Size0a",              STAMUNIT_OCCURENCES,     "Number of 10 byte accesses (R3).");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Sizes[10],        STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Size0b",              STAMUNIT_OCCURENCES,     "Number of 11 byte accesses (R3).");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Sizes[11],        STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Size0c",              STAMUNIT_OCCURENCES,     "Number of 12 byte accesses (R3).");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Sizes[12],        STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Size0d",              STAMUNIT_OCCURENCES,     "Number of 13 byte accesses (R3).");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Sizes[13],        STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Size0e",              STAMUNIT_OCCURENCES,     "Number of 14 byte accesses (R3).");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Sizes[14],        STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Size0f",              STAMUNIT_OCCURENCES,     "Number of 15 byte accesses (R3).");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Sizes[15],        STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Size10",              STAMUNIT_OCCURENCES,     "Number of 16 byte accesses (R3).");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Sizes[16],        STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Size11-2f",           STAMUNIT_OCCURENCES,     "Number of 17-31 byte accesses.");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Sizes[17],        STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Size20-3f",           STAMUNIT_OCCURENCES,     "Number of 32-63 byte accesses.");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Sizes[18],        STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Size40+",             STAMUNIT_OCCURENCES,     "Number of 64+ byte accesses.");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Misaligned[0],    STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Misaligned1",         STAMUNIT_OCCURENCES,     "Number of misaligned access with offset 1 in R3.");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Misaligned[1],    STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Misaligned2",         STAMUNIT_OCCURENCES,     "Number of misaligned access with offset 2 in R3.");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Misaligned[2],    STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Misaligned3",         STAMUNIT_OCCURENCES,     "Number of misaligned access with offset 3 in R3.");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Misaligned[3],    STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Misaligned4",         STAMUNIT_OCCURENCES,     "Number of misaligned access with offset 4 in R3.");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Misaligned[4],    STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Misaligned5",         STAMUNIT_OCCURENCES,     "Number of misaligned access with offset 5 in R3.");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Misaligned[5],    STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Misaligned6",         STAMUNIT_OCCURENCES,     "Number of misaligned access with offset 6 in R3.");
+    STAM_REG(pVM, &pPool->aStatMonitorR3Misaligned[6],    STAMTYPE_PROFILE, "/PGM/Pool/Monitor/R3/Misaligned7",         STAMUNIT_OCCURENCES,     "Number of misaligned access with offset 7 in R3.");
+
+    STAM_REG(pVM, &pPool->StatMonitorR3FaultPT,         STAMTYPE_COUNTER,   "/PGM/Pool/Monitor/R3/Fault/PT",        STAMUNIT_OCCURENCES,     "Nr of handled PT faults.");
+    STAM_REG(pVM, &pPool->StatMonitorR3FaultPD,         STAMTYPE_COUNTER,   "/PGM/Pool/Monitor/R3/Fault/PD",        STAMUNIT_OCCURENCES,     "Nr of handled PD faults.");
+    STAM_REG(pVM, &pPool->StatMonitorR3FaultPDPT,       STAMTYPE_COUNTER,   "/PGM/Pool/Monitor/R3/Fault/PDPT",      STAMUNIT_OCCURENCES,     "Nr of handled PDPT faults.");
+    STAM_REG(pVM, &pPool->StatMonitorR3FaultPML4,       STAMTYPE_COUNTER,   "/PGM/Pool/Monitor/R3/Fault/PML4",      STAMUNIT_OCCURENCES,     "Nr of handled PML4 faults.");
+
+    STAM_REG(pVM, &pPool->cModifiedPages,               STAMTYPE_U16,       "/PGM/Pool/Monitor/cModifiedPages",     STAMUNIT_PAGES,          "The current cModifiedPages value.");
+    STAM_REG(pVM, &pPool->cModifiedPagesHigh,           STAMTYPE_U16_RESET, "/PGM/Pool/Monitor/cModifiedPagesHigh", STAMUNIT_PAGES,          "The high watermark for cModifiedPages.");
+    STAM_REG(pVM, &pPool->StatResetDirtyPages,          STAMTYPE_COUNTER,   "/PGM/Pool/Monitor/Dirty/Resets",       STAMUNIT_OCCURENCES,     "Times we've called pgmPoolResetDirtyPages (and there were dirty page).");
+    STAM_REG(pVM, &pPool->StatDirtyPage,                STAMTYPE_COUNTER,   "/PGM/Pool/Monitor/Dirty/Pages",        STAMUNIT_OCCURENCES,     "Times we've called pgmPoolAddDirtyPage.");
+    STAM_REG(pVM, &pPool->StatDirtyPageDupFlush,        STAMTYPE_COUNTER,   "/PGM/Pool/Monitor/Dirty/FlushDup",     STAMUNIT_OCCURENCES,     "Times we've had to flush duplicates for dirty page management.");
+    STAM_REG(pVM, &pPool->StatDirtyPageOverFlowFlush,   STAMTYPE_COUNTER,   "/PGM/Pool/Monitor/Dirty/FlushOverflow",STAMUNIT_OCCURENCES,     "Times we've had to flush because of overflow.");
+    STAM_REG(pVM, &pPool->StatCacheHits,                STAMTYPE_COUNTER,   "/PGM/Pool/Cache/Hits",                 STAMUNIT_OCCURENCES, "The number of pgmPoolAlloc calls satisfied by the cache.");
+    STAM_REG(pVM, &pPool->StatCacheMisses,              STAMTYPE_COUNTER,   "/PGM/Pool/Cache/Misses",               STAMUNIT_OCCURENCES, "The number of pgmPoolAlloc calls not statisfied by the cache.");
+    STAM_REG(pVM, &pPool->StatCacheKindMismatches,      STAMTYPE_COUNTER,   "/PGM/Pool/Cache/KindMismatches",       STAMUNIT_OCCURENCES, "The number of shadow page kind mismatches. (Better be low, preferably 0!)");
+    STAM_REG(pVM, &pPool->StatCacheFreeUpOne,           STAMTYPE_COUNTER,   "/PGM/Pool/Cache/FreeUpOne",            STAMUNIT_OCCURENCES, "The number of times the cache was asked to free up a page.");
+    STAM_REG(pVM, &pPool->StatCacheCacheable,           STAMTYPE_COUNTER,   "/PGM/Pool/Cache/Cacheable",            STAMUNIT_OCCURENCES, "The number of cacheable allocations.");
+    STAM_REG(pVM, &pPool->StatCacheUncacheable,         STAMTYPE_COUNTER,   "/PGM/Pool/Cache/Uncacheable",          STAMUNIT_OCCURENCES, "The number of uncacheable allocations.");
+#endif /* VBOX_WITH_STATISTICS */
+
+#ifdef VBOX_WITH_DEBUGGER
+    /*
+     * Debugger commands.
+     */
+    static bool s_fRegisteredCmds = false;
+    if (!s_fRegisteredCmds)
+    {
+        rc = DBGCRegisterCommands(&g_aCmds[0], RT_ELEMENTS(g_aCmds));
+        if (RT_SUCCESS(rc))
+            s_fRegisteredCmds = true;
+    }
+#endif
+
+    return VINF_SUCCESS;
+}
+
+
+/**
+ * Relocate the page pool data.
+ *
+ * @param   pVM     The cross context VM structure.
+ */
+void pgmR3PoolRelocate(PVM pVM)
+{
+    RT_NOREF(pVM);
+}
+
+
+/**
+ * Grows the shadow page pool.
+ *
+ * I.e. adds more pages to it, assuming that hasn't reached cMaxPages yet.
+ *
+ * @returns VBox status code.
+ * @param   pVM     The cross context VM structure.
+ * @param   pVCpu   The cross context virtual CPU structure of the calling EMT.
+ */
+VMMR3_INT_DECL(int) PGMR3PoolGrow(PVM pVM, PVMCPU pVCpu)
+{
+    /* This used to do a lot of stuff, but it has moved to ring-0 (PGMR0PoolGrow). */
+    AssertReturn(pVM->pgm.s.pPoolR3->cCurPages < pVM->pgm.s.pPoolR3->cMaxPages, VERR_PGM_POOL_MAXED_OUT_ALREADY);
+    int rc = VMMR3CallR0Emt(pVM, pVCpu, VMMR0_DO_PGM_POOL_GROW, 0, NULL);
+    if (rc == VINF_SUCCESS)
+        return rc;
+    LogRel(("PGMR3PoolGrow: rc=%Rrc cCurPages=%#x cMaxPages=%#x\n",
+            rc, pVM->pgm.s.pPoolR3->cCurPages, pVM->pgm.s.pPoolR3->cMaxPages));
+    if (pVM->pgm.s.pPoolR3->cCurPages > 128 && RT_FAILURE_NP(rc))
+        return -rc;
+    return rc;
+}
+
+
+/**
+ * Rendezvous callback used by pgmR3PoolClearAll that clears all shadow pages
+ * and all modification counters.
+ *
+ * This is only called on one of the EMTs while the other ones are waiting for
+ * it to complete this function.
+ *
+ * @returns VINF_SUCCESS (VBox strict status code).
+ * @param   pVM     The cross context VM structure.
+ * @param   pVCpu   The cross context virtual CPU structure of the calling EMT. Unused.
+ * @param   fpvFlushRemTlb  When not NULL, we'll flush the REM TLB as well.
+ *                          (This is the pvUser, so it has to be void *.)
+ *
+ */
+DECLCALLBACK(VBOXSTRICTRC) pgmR3PoolClearAllRendezvous(PVM pVM, PVMCPU pVCpu, void *fpvFlushRemTlb)
+{
+    PPGMPOOL pPool = pVM->pgm.s.CTX_SUFF(pPool);
+    STAM_PROFILE_START(&pPool->StatClearAll, c);
+    NOREF(pVCpu);
+
+    pgmLock(pVM);
+    Log(("pgmR3PoolClearAllRendezvous: cUsedPages=%d fpvFlushRemTlb=%RTbool\n", pPool->cUsedPages, !!fpvFlushRemTlb));
+
+    /*
+     * Iterate all the pages until we've encountered all that are in use.
+     * This is a simple but not quite optimal solution.
+     */
+    unsigned cModifiedPages = 0; NOREF(cModifiedPages);
+    unsigned cLeft = pPool->cUsedPages;
+    uint32_t iPage = pPool->cCurPages;
+    while (--iPage >= PGMPOOL_IDX_FIRST)
+    {
+        PPGMPOOLPAGE pPage = &pPool->aPages[iPage];
+        if (pPage->GCPhys != NIL_RTGCPHYS)
+        {
+            switch (pPage->enmKind)
+            {
+                /*
+                 * We only care about shadow page tables that reference physical memory
+                 */
+#ifdef PGM_WITH_LARGE_PAGES
+                case PGMPOOLKIND_EPT_PD_FOR_PHYS: /* Large pages reference 2 MB of physical memory, so we must clear them. */
+                    if (pPage->cPresent)
+                    {
+                        PX86PDPAE pShwPD = (PX86PDPAE)PGMPOOL_PAGE_2_PTR_V2(pPool->CTX_SUFF(pVM), pVCpu, pPage);
+                        for (unsigned i = 0; i < RT_ELEMENTS(pShwPD->a); i++)
+                        {
+                            if (    pShwPD->a[i].n.u1Present
+                                &&  pShwPD->a[i].b.u1Size)
+                            {
+                                Assert(!(pShwPD->a[i].u & PGM_PDFLAGS_MAPPING));
+                                pShwPD->a[i].u = 0;
+                                Assert(pPage->cPresent);
+                                pPage->cPresent--;
+                            }
+                        }
+                        if (pPage->cPresent == 0)
+                            pPage->iFirstPresent = NIL_PGMPOOL_PRESENT_INDEX;
+                    }
+                    goto default_case;
+
+                case PGMPOOLKIND_PAE_PD_PHYS:   /* Large pages reference 2 MB of physical memory, so we must clear them. */
+                    if (pPage->cPresent)
+                    {
+                        PEPTPD pShwPD = (PEPTPD)PGMPOOL_PAGE_2_PTR_V2(pPool->CTX_SUFF(pVM), pVCpu, pPage);
+                        for (unsigned i = 0; i < RT_ELEMENTS(pShwPD->a); i++)
+                        {
+                            Assert((pShwPD->a[i].u & UINT64_C(0xfff0000000000f80)) == 0);
+                            if (    pShwPD->a[i].n.u1Present
+                                &&  pShwPD->a[i].b.u1Size)
+                            {
+                                Assert(!(pShwPD->a[i].u & PGM_PDFLAGS_MAPPING));
+                                pShwPD->a[i].u = 0;
+                                Assert(pPage->cPresent);
+                                pPage->cPresent--;
+                            }
+                        }
+                        if (pPage->cPresent == 0)
+                            pPage->iFirstPresent = NIL_PGMPOOL_PRESENT_INDEX;
+                    }
+                    goto default_case;
+#endif /* PGM_WITH_LARGE_PAGES */
+
+                case PGMPOOLKIND_32BIT_PT_FOR_32BIT_PT:
+                case PGMPOOLKIND_32BIT_PT_FOR_32BIT_4MB:
+                case PGMPOOLKIND_PAE_PT_FOR_32BIT_PT:
+                case PGMPOOLKIND_PAE_PT_FOR_32BIT_4MB:
+                case PGMPOOLKIND_PAE_PT_FOR_PAE_PT:
+                case PGMPOOLKIND_PAE_PT_FOR_PAE_2MB:
+                case PGMPOOLKIND_32BIT_PT_FOR_PHYS:
+                case PGMPOOLKIND_PAE_PT_FOR_PHYS:
+                case PGMPOOLKIND_EPT_PT_FOR_PHYS:
+                {
+                    if (pPage->cPresent)
+                    {
+                        void *pvShw = PGMPOOL_PAGE_2_PTR_V2(pPool->CTX_SUFF(pVM), pVCpu, pPage);
+                        STAM_PROFILE_START(&pPool->StatZeroPage, z);
+#if 0
+                        /* Useful check for leaking references; *very* expensive though. */
+                        switch (pPage->enmKind)
+                        {
+                            case PGMPOOLKIND_PAE_PT_FOR_32BIT_PT:
+                            case PGMPOOLKIND_PAE_PT_FOR_32BIT_4MB:
+                            case PGMPOOLKIND_PAE_PT_FOR_PAE_PT:
+                            case PGMPOOLKIND_PAE_PT_FOR_PAE_2MB:
+                            case PGMPOOLKIND_PAE_PT_FOR_PHYS:
+                            {
+                                bool fFoundFirst = false;
+                                PPGMSHWPTPAE pPT = (PPGMSHWPTPAE)pvShw;
+                                for (unsigned ptIndex = 0; ptIndex < RT_ELEMENTS(pPT->a); ptIndex++)
+                                {
+                                    if (pPT->a[ptIndex].u)
+                                    {
+                                        if (!fFoundFirst)
+                                        {
+                                            AssertFatalMsg(pPage->iFirstPresent <= ptIndex, ("ptIndex = %d first present = %d\n", ptIndex, pPage->iFirstPresent));
+                                            if (pPage->iFirstPresent != ptIndex)
+                                                Log(("ptIndex = %d first present = %d\n", ptIndex, pPage->iFirstPresent));
+                                            fFoundFirst = true;
+                                        }
+                                        if (PGMSHWPTEPAE_IS_P(pPT->a[ptIndex]))
+                                        {
+                                            pgmPoolTracDerefGCPhysHint(pPool, pPage, PGMSHWPTEPAE_GET_HCPHYS(pPT->a[ptIndex]), NIL_RTGCPHYS);
+                                            if (pPage->iFirstPresent == ptIndex)
+                                                pPage->iFirstPresent = NIL_PGMPOOL_PRESENT_INDEX;
+                                        }
+                                    }
+                                }
+                                AssertFatalMsg(pPage->cPresent == 0, ("cPresent = %d pPage = %RGv\n", pPage->cPresent, pPage->GCPhys));
+                                break;
+                            }
+                            default:
+                                break;
+                        }
+#endif
+                        ASMMemZeroPage(pvShw);
+                        STAM_PROFILE_STOP(&pPool->StatZeroPage, z);
+                        pPage->cPresent = 0;
+                        pPage->iFirstPresent = NIL_PGMPOOL_PRESENT_INDEX;
+                    }
+                }
+                RT_FALL_THRU();
+#ifdef PGM_WITH_LARGE_PAGES
+                default_case:
+#endif
+                default:
+                    Assert(!pPage->cModifications || ++cModifiedPages);
+                    Assert(pPage->iModifiedNext == NIL_PGMPOOL_IDX || pPage->cModifications);
+                    Assert(pPage->iModifiedPrev == NIL_PGMPOOL_IDX || pPage->cModifications);
+                    pPage->iModifiedNext = NIL_PGMPOOL_IDX;
+                    pPage->iModifiedPrev = NIL_PGMPOOL_IDX;
+                    pPage->cModifications = 0;
+                    break;
+
+            }
+            if (!--cLeft)
+                break;
+        }
+    }
+
+#ifndef DEBUG_michael
+    AssertMsg(cModifiedPages == pPool->cModifiedPages, ("%d != %d\n", cModifiedPages, pPool->cModifiedPages));
+#endif
+    pPool->iModifiedHead = NIL_PGMPOOL_IDX;
+    pPool->cModifiedPages = 0;
+
+    /*
+     * Clear all the GCPhys links and rebuild the phys ext free list.
+     */
+    for (PPGMRAMRANGE pRam = pPool->CTX_SUFF(pVM)->pgm.s.CTX_SUFF(pRamRangesX);
+         pRam;
+         pRam = pRam->CTX_SUFF(pNext))
+    {
+        iPage = pRam->cb >> PAGE_SHIFT;
+        while (iPage-- > 0)
+            PGM_PAGE_SET_TRACKING(pVM, &pRam->aPages[iPage], 0);
+    }
+
+    pPool->iPhysExtFreeHead = 0;
+    PPGMPOOLPHYSEXT paPhysExts = pPool->CTX_SUFF(paPhysExts);
+    const unsigned cMaxPhysExts = pPool->cMaxPhysExts;
+    for (unsigned i = 0; i < cMaxPhysExts; i++)
+    {
+        paPhysExts[i].iNext = i + 1;
+        paPhysExts[i].aidx[0] = NIL_PGMPOOL_IDX;
+        paPhysExts[i].apte[0] = NIL_PGMPOOL_PHYSEXT_IDX_PTE;
+        paPhysExts[i].aidx[1] = NIL_PGMPOOL_IDX;
+        paPhysExts[i].apte[1] = NIL_PGMPOOL_PHYSEXT_IDX_PTE;
+        paPhysExts[i].aidx[2] = NIL_PGMPOOL_IDX;
+        paPhysExts[i].apte[2] = NIL_PGMPOOL_PHYSEXT_IDX_PTE;
+    }
+    paPhysExts[cMaxPhysExts - 1].iNext = NIL_PGMPOOL_PHYSEXT_INDEX;
+
+
+#ifdef PGMPOOL_WITH_OPTIMIZED_DIRTY_PT
+    /* Reset all dirty pages to reactivate the page monitoring. */
+    /* Note: we must do this *after* clearing all page references and shadow page tables as there might be stale references to
+     *       recently removed MMIO ranges around that might otherwise end up asserting in pgmPoolTracDerefGCPhysHint
+     */
+    for (unsigned i = 0; i < RT_ELEMENTS(pPool->aDirtyPages); i++)
+    {
+        unsigned idxPage = pPool->aidxDirtyPages[i];
+        if (idxPage == NIL_PGMPOOL_IDX)
+            continue;
+
+        PPGMPOOLPAGE pPage = &pPool->aPages[idxPage];
+        Assert(pPage->idx == idxPage);
+        Assert(pPage->iMonitoredNext == NIL_PGMPOOL_IDX && pPage->iMonitoredPrev == NIL_PGMPOOL_IDX);
+
+        AssertMsg(pPage->fDirty, ("Page %RGp (slot=%d) not marked dirty!", pPage->GCPhys, i));
+
+        Log(("Reactivate dirty page %RGp\n", pPage->GCPhys));
+
+        /* First write protect the page again to catch all write accesses. (before checking for changes -> SMP) */
+        int rc = PGMHandlerPhysicalReset(pVM, pPage->GCPhys & PAGE_BASE_GC_MASK);
+        AssertRCSuccess(rc);
+        pPage->fDirty = false;
+
+        pPool->aidxDirtyPages[i] = NIL_PGMPOOL_IDX;
+    }
+
+    /* Clear all dirty pages. */
+    pPool->idxFreeDirtyPage = 0;
+    pPool->cDirtyPages      = 0;
+#endif
+
+    /* Clear the PGM_SYNC_CLEAR_PGM_POOL flag on all VCPUs to prevent redundant flushes. */
+    for (VMCPUID idCpu = 0; idCpu < pVM->cCpus; idCpu++)
+        pVM->apCpusR3[idCpu]->pgm.s.fSyncFlags &= ~PGM_SYNC_CLEAR_PGM_POOL;
+
+    /* Flush job finished. */
+    VM_FF_CLEAR(pVM, VM_FF_PGM_POOL_FLUSH_PENDING);
+    pPool->cPresent = 0;
+    pgmUnlock(pVM);
+
+    PGM_INVL_ALL_VCPU_TLBS(pVM);
+
+    if (fpvFlushRemTlb)
+        for (VMCPUID idCpu = 0; idCpu < pVM->cCpus; idCpu++)
+            CPUMSetChangedFlags(pVM->apCpusR3[idCpu], CPUM_CHANGED_GLOBAL_TLB_FLUSH);
+
+    STAM_PROFILE_STOP(&pPool->StatClearAll, c);
+    return VINF_SUCCESS;
+}
+
+
+/**
+ * Clears the shadow page pool.
+ *
+ * @param   pVM             The cross context VM structure.
+ * @param   fFlushRemTlb    When set, the REM TLB is scheduled for flushing as
+ *                          well.
+ */
+void pgmR3PoolClearAll(PVM pVM, bool fFlushRemTlb)
+{
+    int rc = VMMR3EmtRendezvous(pVM, VMMEMTRENDEZVOUS_FLAGS_TYPE_ONCE, pgmR3PoolClearAllRendezvous, &fFlushRemTlb);
+    AssertRC(rc);
+}
+
+
+/**
+ * Protect all pgm pool page table entries to monitor writes
+ *
+ * @param   pVM         The cross context VM structure.
+ *
+ * @remarks ASSUMES the caller will flush all TLBs!!
+ */
+void pgmR3PoolWriteProtectPages(PVM pVM)
+{
+    PGM_LOCK_ASSERT_OWNER(pVM);
+    PPGMPOOL pPool = pVM->pgm.s.CTX_SUFF(pPool);
+    unsigned cLeft = pPool->cUsedPages;
+    unsigned iPage = pPool->cCurPages;
+    while (--iPage >= PGMPOOL_IDX_FIRST)
+    {
+        PPGMPOOLPAGE pPage = &pPool->aPages[iPage];
+        if (    pPage->GCPhys != NIL_RTGCPHYS
+            &&  pPage->cPresent)
+        {
+            union
+            {
+                void           *pv;
+                PX86PT          pPT;
+                PPGMSHWPTPAE    pPTPae;
+                PEPTPT          pPTEpt;
+            } uShw;
+            uShw.pv = PGMPOOL_PAGE_2_PTR(pVM, pPage);
+
+            switch (pPage->enmKind)
+            {
+                /*
+                 * We only care about shadow page tables.
+                 */
+                case PGMPOOLKIND_32BIT_PT_FOR_32BIT_PT:
+                case PGMPOOLKIND_32BIT_PT_FOR_32BIT_4MB:
+                case PGMPOOLKIND_32BIT_PT_FOR_PHYS:
+                    for (unsigned iShw = 0; iShw < RT_ELEMENTS(uShw.pPT->a); iShw++)
+                    {
+                        if (uShw.pPT->a[iShw].n.u1Present)
+                            uShw.pPT->a[iShw].n.u1Write = 0;
+                    }
+                    break;
+
+                case PGMPOOLKIND_PAE_PT_FOR_32BIT_PT:
+                case PGMPOOLKIND_PAE_PT_FOR_32BIT_4MB:
+                case PGMPOOLKIND_PAE_PT_FOR_PAE_PT:
+                case PGMPOOLKIND_PAE_PT_FOR_PAE_2MB:
+                case PGMPOOLKIND_PAE_PT_FOR_PHYS:
+                    for (unsigned iShw = 0; iShw < RT_ELEMENTS(uShw.pPTPae->a); iShw++)
+                    {
+                        if (PGMSHWPTEPAE_IS_P(uShw.pPTPae->a[iShw]))
+                            PGMSHWPTEPAE_SET_RO(uShw.pPTPae->a[iShw]);
+                    }
+                    break;
+
+                case PGMPOOLKIND_EPT_PT_FOR_PHYS:
+                    for (unsigned iShw = 0; iShw < RT_ELEMENTS(uShw.pPTEpt->a); iShw++)
+                    {
+                        if (uShw.pPTEpt->a[iShw].n.u1Present)
+                            uShw.pPTEpt->a[iShw].n.u1Write = 0;
+                    }
+                    break;
+
+                default:
+                    break;
+            }
+            if (!--cLeft)
+                break;
+        }
+    }
+}
+
+#ifdef VBOX_WITH_DEBUGGER
+/**
+ * @callback_method_impl{FNDBGCCMD, The '.pgmpoolcheck' command.}
+ */
+static DECLCALLBACK(int) pgmR3PoolCmdCheck(PCDBGCCMD pCmd, PDBGCCMDHLP pCmdHlp, PUVM pUVM, PCDBGCVAR paArgs, unsigned cArgs)
+{
+    DBGC_CMDHLP_REQ_UVM_RET(pCmdHlp, pCmd, pUVM);
+    PVM pVM = pUVM->pVM;
+    VM_ASSERT_VALID_EXT_RETURN(pVM, VERR_INVALID_VM_HANDLE);
+    DBGC_CMDHLP_ASSERT_PARSER_RET(pCmdHlp, pCmd, -1, cArgs == 0);
+    uint32_t cErrors = 0;
+    NOREF(paArgs);
+
+    PPGMPOOL pPool = pVM->pgm.s.CTX_SUFF(pPool);
+    for (unsigned i = 0; i < pPool->cCurPages; i++)
+    {
+        PPGMPOOLPAGE    pPage     = &pPool->aPages[i];
+        bool            fFirstMsg = true;
+
+        /** @todo cover other paging modes too. */
+        if (pPage->enmKind == PGMPOOLKIND_PAE_PT_FOR_PAE_PT)
+        {
+            PPGMSHWPTPAE pShwPT = (PPGMSHWPTPAE)PGMPOOL_PAGE_2_PTR(pPool->CTX_SUFF(pVM), pPage);
+            {
+                PX86PTPAE       pGstPT;
+                PGMPAGEMAPLOCK  LockPage;
+                int rc = PGMPhysGCPhys2CCPtrReadOnly(pVM, pPage->GCPhys, (const void **)&pGstPT, &LockPage);     AssertReleaseRC(rc);
+
+                /* Check if any PTEs are out of sync. */
+                for (unsigned j = 0; j < RT_ELEMENTS(pShwPT->a); j++)
+                {
+                    if (PGMSHWPTEPAE_IS_P(pShwPT->a[j]))
+                    {
+                        RTHCPHYS HCPhys = NIL_RTHCPHYS;
+                        rc = PGMPhysGCPhys2HCPhys(pPool->CTX_SUFF(pVM), pGstPT->a[j].u & X86_PTE_PAE_PG_MASK, &HCPhys);
+                        if (   rc != VINF_SUCCESS
+                            || PGMSHWPTEPAE_GET_HCPHYS(pShwPT->a[j]) != HCPhys)
+                        {
+                            if (fFirstMsg)
+                            {
+                                DBGCCmdHlpPrintf(pCmdHlp, "Check pool page %RGp\n", pPage->GCPhys);
+                                fFirstMsg = false;
+                            }
+                            DBGCCmdHlpPrintf(pCmdHlp, "Mismatch HCPhys: rc=%Rrc idx=%d guest %RX64 shw=%RX64 vs %RHp\n", rc, j, pGstPT->a[j].u, PGMSHWPTEPAE_GET_LOG(pShwPT->a[j]), HCPhys);
+                            cErrors++;
+                        }
+                        else if (   PGMSHWPTEPAE_IS_RW(pShwPT->a[j])
+                                 && !pGstPT->a[j].n.u1Write)
+                        {
+                            if (fFirstMsg)
+                            {
+                                DBGCCmdHlpPrintf(pCmdHlp, "Check pool page %RGp\n", pPage->GCPhys);
+                                fFirstMsg = false;
+                            }
+                            DBGCCmdHlpPrintf(pCmdHlp, "Mismatch r/w gst/shw: idx=%d guest %RX64 shw=%RX64 vs %RHp\n", j, pGstPT->a[j].u, PGMSHWPTEPAE_GET_LOG(pShwPT->a[j]), HCPhys);
+                            cErrors++;
+                        }
+                    }
+                }
+                PGMPhysReleasePageMappingLock(pVM, &LockPage);
+            }
+
+            /* Make sure this page table can't be written to from any shadow mapping. */
+            RTHCPHYS HCPhysPT = NIL_RTHCPHYS;
+            int rc = PGMPhysGCPhys2HCPhys(pPool->CTX_SUFF(pVM), pPage->GCPhys, &HCPhysPT);
+            AssertMsgRC(rc, ("PGMPhysGCPhys2HCPhys failed with rc=%d for %RGp\n", rc, pPage->GCPhys));
+            if (rc == VINF_SUCCESS)
+            {
+                for (unsigned j = 0; j < pPool->cCurPages; j++)
+                {
+                    PPGMPOOLPAGE pTempPage = &pPool->aPages[j];
+
+                    if (pTempPage->enmKind == PGMPOOLKIND_PAE_PT_FOR_PAE_PT)
+                    {
+                        PPGMSHWPTPAE pShwPT2 = (PPGMSHWPTPAE)PGMPOOL_PAGE_2_PTR(pPool->CTX_SUFF(pVM), pTempPage);
+
+                        for (unsigned k = 0; k < RT_ELEMENTS(pShwPT->a); k++)
+                        {
+                            if (    PGMSHWPTEPAE_IS_P_RW(pShwPT2->a[k])
+# ifdef PGMPOOL_WITH_OPTIMIZED_DIRTY_PT
+                                &&  !pPage->fDirty
+# endif
+                                &&  PGMSHWPTEPAE_GET_HCPHYS(pShwPT2->a[k]) == HCPhysPT)
+                            {
+                                if (fFirstMsg)
+                                {
+                                    DBGCCmdHlpPrintf(pCmdHlp, "Check pool page %RGp\n", pPage->GCPhys);
+                                    fFirstMsg = false;
+                                }
+                                DBGCCmdHlpPrintf(pCmdHlp, "Mismatch: r/w: GCPhys=%RGp idx=%d shw %RX64 %RX64\n", pTempPage->GCPhys, k, PGMSHWPTEPAE_GET_LOG(pShwPT->a[k]), PGMSHWPTEPAE_GET_LOG(pShwPT2->a[k]));
+                                cErrors++;
+                            }
+                        }
+                    }
+                }
+            }
+        }
+    }
+    if (cErrors > 0)
+        return DBGCCmdHlpFail(pCmdHlp, pCmd, "Found %#x errors", cErrors);
+    return VINF_SUCCESS;
+}
+#endif /* VBOX_WITH_DEBUGGER */