Changeset 80168 in vbox for trunk/src

Timestamp:

Aug 7, 2019 12:48:58 AM (5 years ago)

Author:

vboxsync

Message:

Fixed offset usage that caused reaching into wrong values of newest driver-side config struct, and further refined logging (see #9440, Comment 42)

Location:

trunk/src/VBox/Devices

Files:

• Storage/DevVirtioSCSI.cpp (modified) (13 diffs)
• VirtIO/Virtio_1_0.cpp (modified) (18 diffs)
• VirtIO/Virtio_1_0.h (modified) (3 diffs)
• VirtIO/Virtio_1_0_impl.h (added)

trunk/src/VBox/Devices/Storage/DevVirtioSCSI.cpp

@@ -60 +60 @@
 #define VIRTIOSCSI_REGION_PCI_CAP                   2
 
-/**
- * Definitions that follow are based on the VirtIO 1.0 specification.
- * Struct names are the same. The field names have been adapted to VirtualBox
- * data type + camel case annotation, with the original field name from the
- * VirtIO specification in the field's comment.
- */
-
 #define MATCH_SCSI_CONFIG(member) \
     ((int)uOffset >= RT_OFFSETOF(VIRTIO_SCSI_CONFIG_T, member) \
@@ -75 +68 @@
 
 #define LOG_ACCESSOR(member) \
-        LogFunc(("Guest %s %s [%d:%d]: %.*Rhxs\n", \
-                  fWrite ? "wrote" : "read ", #member,  mOffset, mOffset + cb, cb, pv));
+        virtioLogMappedIoValue(__FUNCTION__, #member, pv, cb, uMemberOffset, fWrite, false, 0);
 
 #define SCSI_CONFIG_ACCESSOR(member) \
     { \
-        uint32_t mOffset = uOffset - RT_OFFSETOF(VIRTIO_SCSI_CONFIG_T, member); \
+        uint32_t uMemberOffset = uOffset - RT_OFFSETOF(VIRTIO_SCSI_CONFIG_T, member); \
         if (fWrite) \
-            memcpy(((char *)&pThis->virtioScsiConfig.member) + uOffset, (const char *)pv, cb); \
+            memcpy(((char *)&pThis->virtioScsiConfig.member) + uMemberOffset, (const char *)pv, cb); \
         else \
-            memcpy((char *)pv, (const char *)(((char *)&pThis->virtioScsiConfig.member) + uOffset), cb); \
+            memcpy((char *)pv, (const char *)(((char *)&pThis->virtioScsiConfig.member) + uMemberOffset), cb); \
         LOG_ACCESSOR(member); \
     }
@@ -90 +82 @@
 #define SCSI_CONFIG_ACCESSOR_READONLY(member) \
     { \
-        uint32_t mOffset = uOffset - RT_OFFSETOF(VIRTIO_SCSI_CONFIG_T, member); \
+        uint32_t uMemberOffset = uOffset - RT_OFFSETOF(VIRTIO_SCSI_CONFIG_T, member); \
         if (fWrite) \
             LogFunc(("Guest attempted to write readonly virtio_pci_common_cfg.%s\n", #member)); \
         else \
         { \
-            memcpy((char *)pv, (const char *)(((char *)&pThis->virtioScsiConfig.member) + uOffset), cb); \
+            memcpy((char *)pv, (const char *)(((char *)&pThis->virtioScsiConfig.member) + uMemberOffset), cb); \
             LOG_ACCESSOR(member); \
         } \
     }
 
+/**
+ * Definitions that follow are based on the VirtIO 1.0 specification.
+ * Struct names are the same. The field names have been adapted to VirtualBox
+ * data type + camel case annotation, with the original field name from the
+ * VirtIO specification in the field's comment.
+ */
 
 /** @name VirtIO 1.0 SCSI Host feature bits
@@ -112 +110 @@
  * Features VirtIO 1.0 Host SCSI controller offers guest driver
  */
-#define VIRTIOSCSI_HOST_SCSI_FEATURES_OFFERED         VIRTIOSCSI_F_INOUT   \
-                                                    | VIRTIOSCSI_F_HOTPLUG \
-                                                    | VIRTIOSCSI_F_CHANGE  \
-                                                    | VIRTIOSCSI_F_T10_PI  \
+#define VIRTIOSCSI_HOST_SCSI_FEATURES_OFFERED \
+            (VIRTIOSCSI_F_INOUT | VIRTIOSCSI_F_HOTPLUG | VIRTIOSCSI_F_CHANGE | VIRTIOSCSI_F_T10_PI)
 
 typedef struct virtio_scsi_config
@@ -167 +163 @@
 } VIRTIO_SCSI_REQ_CMD_T, *PVIRTIO_SCSI_REQ_CMD_T;
 
-/** Command-specific response values */
+/** @name VirtIO 1.0 SCSI req command-specific response values
+ * @{  */
 #define VIRTIOSCSI_S_OK                            0       /* control, command   */
 #define VIRTIOSCSI_S_OVERRUN                       1       /* control */
@@ -179 +176 @@
 #define VIRTIOSCSI_S_FAILURE                       9       /* control, command */
 #define VIRTIOSCSI_S_INCORRECT_LUN                12       /* command */
-
-
-/** task_attr */
+/** @} */
+
+
+/** @name VirtIO 1.0 SCSI Command-specific task_attr values
+ * @{  */
 #define VIRTIOSCSI_S_SIMPLE                        0
 #define VIRTIOSCSI_S_ORDERED                       1
 #define VIRTIOSCSI_S_HEAD                          2
 #define VIRTIOSCSI_S_ACA                           3
+/** @} */
 
 #define VIRTIOSCSI_T_TMF                           0
@@ -208 +208 @@
 } VIRTIO_SCSI_CTRL_BUF_T, *PVIRTIO_SCSI_CTRL_BUF_T;
 
-/* command-specific response values */
-
+/** @name VirtIO 1.0 SCSI tmf control command-specific response values
+ * @{  */
 #define VIRTIOSCSI_S_FUNCTION_COMPLETE            0
 #define VIRTIOSCSI_S_FUNCTION_SUCCEEDED           10
 #define VIRTIOSCSI_S_FUNCTION_REJECTED            11
+/** @} */
 
 #define VIRTIOSCSI_T_AN_QUERY                     1         /** Asynchronous notification query */
@@ -242 +243 @@
     uint8_t  response;                                       /** response        */
 } VIRTIO_SCSI_CTRL_T, *PVIRTIO_SCSI_CTRL_T;
+
 
 #define VIRTIOSCSI_T_NO_EVENT                   0
@@ -758 +760 @@
 }
 
-static int virtioScsiR3ConfigAccess(PVIRTIOSCSI pThis, uint32_t uOffset,
+static int virtioScsiR3CfgAccessed(PVIRTIOSCSI pThis, uint32_t uOffset,
                                     const void *pv, size_t cb, uint8_t fWrite)
 {
@@ -825 +827 @@
  * @param   pDevIns     The device instance.
  * @param   uOffset     Offset within device specific capabilities struct
- * @param   pv       Buffer in which to save read data
+ * @param   pv          Buffer in which to save read data
  * @param   cb          Number of bytes to read
  */
@@ -836 +838 @@
 //              uOffset, cb));
 
-    rc = virtioScsiR3ConfigAccess(pThis, uOffset, pv, cb, false);
+    rc = virtioScsiR3CfgAccessed(pThis, uOffset, pv, cb, false);
 
     return rc;
@@ -847 +849 @@
  * @param   pDevIns     The device instance.
  * @param   uOffset     Offset within device specific capabilities struct
- * @param   pv       Buffer in which to save read data
+ * @param   pv          Buffer in which to save read data
  * @param   cb          Number of bytes to write
  */
@@ -858 +860 @@
 //              uOffset, cb));
 
-    rc = virtioScsiR3ConfigAccess(pThis, uOffset, pv, cb, true);
+    rc = virtioScsiR3CfgAccessed(pThis, uOffset, pv, cb, true);
 
     return rc;

trunk/src/VBox/Devices/VirtIO/Virtio_1_0.cpp

@@ -28 +28 @@
 #include <VBox/vmm/pdmdev.h>
 #include "Virtio_1_0.h"
+#include "Virtio_1_0_impl.h"
 
 #define INSTANCE(pState) pState->szInstance
@@ -35 +36 @@
 # define QUEUENAME(s, q) (q->pcszName)
 #endif
-
-
-/**
-* Returns true if physical address and access length are within the mapped capability struct.
-*
-* Actual Parameters:
-*     [IN]  pPhysCapStruct - Pointer to MMIO mapped capability struct
-*     [IN]  pCfgCap        - Pointer to capability in PCI configuration area
-*     [OUT] fMatched       - True if GCPhysAddr is within the physically mapped capability.
-*
-* Implied parameters:
-*     [IN]  GCPhysAddr     - Physical address accessed (via MMIO callback)
-*     [IN]  cb             - Number of bytes to access
-*     [OUT] result          - true or false
-*
-*/
-#define MATCH_VIRTIO_CAP_STRUCT(pGcPhysCapData, pCfgCap, fMatched) \
-        bool fMatched = false; \
-        if (pGcPhysCapData && pCfgCap && GCPhysAddr >= (RTGCPHYS)pGcPhysCapData \
-            && GCPhysAddr < ((RTGCPHYS)pGcPhysCapData + ((PVIRTIO_PCI_CAP_T)pCfgCap)->uLength) \
-            && cb <= ((PVIRTIO_PCI_CAP_T)pCfgCap)->uLength) \
-                fMatched = true;
-
-/**
- * This macro resolves to boolean true if uoff is within the specified member offset and length.
- *
- * Actual Parameters:
- *     [IN] member      - Member of VIRTIO_PCI_COMMON_CFG_T
- *
- * Implied Parameters:
- *     [IN]  uoff        - Offset into VIRTIO_PCI_COMMON_CFG_T
- *     [IN]  cb          - Number of bytes to access
- *     [OUT] result      - true or false
- */
-#define COMMON_CFG(member) \
-           (uoff >= RT_OFFSETOF(VIRTIO_PCI_COMMON_CFG_T, member) \
-        &&  uoff < (uint32_t)(RT_OFFSETOF(VIRTIO_PCI_COMMON_CFG_T, member) \
-                             + RT_SIZEOFMEMB(VIRTIO_PCI_COMMON_CFG_T, member)) \
-        &&   cb <= RT_SIZEOFMEMB(VIRTIO_PCI_COMMON_CFG_T, member) \
-                  - (uoff - RT_OFFSETOF(VIRTIO_PCI_COMMON_CFG_T, member)))
-
-#define LOG_ACCESSOR(member) \
-        LogFunc(("Guest %s %s[%d:%d]: %.*Rhxs\n", \
-                  fWrite ? "wrote" : "read ", #member, foff, foff + cb, cb, pv));
-
-#define LOG_INDEXED_ACCESSOR(member, idx) \
-        LogFunc(("Guest %s %s[%d][%d:%d]: %.*Rhxs\n", \
-                  fWrite ? "wrote" : "read ", #member, idx, foff, foff + cb, cb, pv));
-
-#define ACCESSOR(member) \
-    { \
-        uint32_t foff = uoff - RT_OFFSETOF(VIRTIO_PCI_COMMON_CFG_T, member); \
-        if (fWrite) \
-            memcpy(((char *)&pVirtio->member) + uoff, (const char *)pv, cb); \
-        else \
-            memcpy((char *)pv, (const char *)(((char *)&pVirtio->member) + uoff), cb); \
-        LOG_ACCESSOR(member); \
-    }
-
-#define ACCESSOR_WITH_IDX(member, idx) \
-    { \
-        uint32_t foff = uoff - RT_OFFSETOF(VIRTIO_PCI_COMMON_CFG_T, member); \
-        if (fWrite) \
-            memcpy(((char *)(pVirtio->member + idx)) + uoff, (const char *)pv, cb); \
-        else \
-            memcpy((char *)pv, (const char *)(((char *)(pVirtio->member + idx)) + uoff), cb); \
-        LOG_INDEXED_ACCESSOR(member, idx); \
-    }
-
-#define ACCESSOR_READONLY(member) \
-    { \
-        uint32_t foff = uoff - RT_OFFSETOF(VIRTIO_PCI_COMMON_CFG_T, member); \
-        if (fWrite) \
-            LogFunc(("Guest attempted to write readonly virtio_pci_common_cfg.%s\n", #member)); \
-        else \
-        { \
-            memcpy((char *)pv, (const char *)(((char *)&pVirtio->member) + uoff), cb); \
-            LOG_ACCESSOR(member); \
-        } \
-    }
-
-#define ACCESSOR_READONLY_WITH_IDX(member, idx) \
-    { \
-        uint32_t foff = uoff - RT_OFFSETOF(VIRTIO_PCI_COMMON_CFG_T, member); \
-        if (fWrite) \
-            LogFunc(("Guest attempted to write readonly virtio_pci_common_cfg.%s[%d]\n", #member, idx)); \
-        else \
-        { \
-            memcpy((char *)pv, ((char *)(pVirtio->member + idx)) + uoff, cb); \
-            LOG_INDEXED_ACCESSOR(member, idx); \
-        } \
-    }
-
-
-#ifdef VBOX_DEVICE_STRUCT_TESTCASE
-#  define virtioDumpState(x, s)  do {} while (0)
-#else
-#  ifdef DEBUG /* This still needs to be migrated to VirtIO 1.0 */
-__attribute__((unused))
-static void virtioDumpState(PVIRTIOSTATE pState, const char *pcszCaller)
-{
-    RT_NOREF2(pState, pcszCaller);
-    /* PK TODO, dump state features, selector, status, ISR, queue info (iterate),
-                descriptors, avail, used, size, indices, address
-                each by variable name on new line, indented slightly */
-}
-#endif
-
 
 void virtQueueReadDesc(PVIRTIOSTATE pState, PVIRTQUEUE pVirtQueue, uint32_t idx, PVIRTQUEUEDESC pDesc)
@@ -466 +359 @@
  * @param   pSSM        The handle to the saved state.
  */
-int virtioSaveExec(PVIRTIOSTATE pState, PSSMHANDLE pSSM)
-{
-    RT_NOREF2(pState, pSSM);
+int virtioSaveExec(PVIRTIOSTATE pVirtio, PSSMHANDLE pSSM)
+{
     int rc = VINF_SUCCESS;
-//    virtioDumpState(pState, "virtioSaveExec");
+    virtioDumpState(pVirtio, "virtioSaveExec");
+    RT_NOREF(pSSM);
     /*
      * PK TODO save guest features, queue selector, sttus ISR,
@@ -490 +383 @@
  * @param   uPass       The data pass.
  */
-int virtioLoadExec(PVIRTIOSTATE pState, PSSMHANDLE pSSM, uint32_t uVersion, uint32_t uPass, uint32_t nQueues)
-{
-    RT_NOREF5(pState, pSSM, uVersion, uPass, nQueues);
+int virtioLoadExec(PVIRTIOSTATE pVirtio, PSSMHANDLE pSSM, uint32_t uVersion, uint32_t uPass, uint32_t nQueues)
+{
+    RT_NOREF5(pVirtio, pSSM, uVersion, uPass, nQueues);
     int rc = VINF_SUCCESS;
+    virtioDumpState(pVirtio, "virtioLoadExec");
 
     /*
@@ -503 +397 @@
     {
     }
-
-//    virtioDumpState(pState, "virtioLoadExec");
-
     return rc;
 }
@@ -612 +503 @@
 {
     RT_NOREF(pVirtio);
-    LogFunc((""));
+    LogFunc(("\n"));
     pVirtio->uDeviceStatus = 0;
 }
@@ -626 +517 @@
  * @param   cb          Number of bytes to read or write
  */
-
-
-int virtioCommonCfgAccessed(PVIRTIOSTATE pVirtio, int fWrite, off_t uoff, unsigned cb, void const *pv)
-{
-    int rv = VINF_SUCCESS;
+int virtioCommonCfgAccessed(PVIRTIOSTATE pVirtio, int fWrite, off_t uOffset, unsigned cb, void const *pv)
+{
+    int rc = VINF_SUCCESS;
     uint64_t val;
     if (COMMON_CFG(uDeviceFeatures))
@@ -638 +527 @@
         else /* Guest READ pCommonCfg->uDeviceFeatures */
         {
-            uint32_t foff = uoff - RT_OFFSETOF(VIRTIO_PCI_COMMON_CFG_T, uDeviceFeatures);
+            uint32_t uIntraOff = uOffset - RT_OFFSETOF(VIRTIO_PCI_COMMON_CFG_T, uDeviceFeatures);
             switch(pVirtio->uDeviceFeaturesSelect)
             {
@@ -644 +533 @@
                     val = pVirtio->uDeviceFeatures & 0xffffffff;
                     memcpy((void *)pv, (const void *)&val, cb);
-                    LogFunc(("Guest read  uDeviceFeatures(LO)[%d:%d]: %.*Rhxs\n",
-                              foff, foff + cb, cb, pv));
+                    LOG_ACCESSOR(uDeviceFeatures);
                     break;
                 case 1:
                     val = (pVirtio->uDeviceFeatures >> 32) & 0xffffffff;
+                    uIntraOff += 4;
                     memcpy((void *)pv, (const void *)&val, cb);
-                    LogFunc(("Guest read  uDeviceFeatures(HI)[%d:%d]: %.*Rhxs\n",
-                              foff, foff + cb, cb, pv));
+                    LOG_ACCESSOR(uDeviceFeatures);
                     break;
                 default:
-                    Log(("Guest read uDeviceFeatures with out of range selector (%d), returning 0\n",
+                    LogFunc(("Guest read uDeviceFeatures with out of range selector (%d), returning 0\n",
                           pVirtio->uDeviceFeaturesSelect));
+                    return VERR_ACCESS_DENIED;
             }
         }
@@ -663 +552 @@
         if (fWrite) /* Guest WRITE pCommonCfg->udriverFeatures */
         {
-            uint32_t foff = uoff - RT_OFFSETOF(VIRTIO_PCI_COMMON_CFG_T, uDriverFeatures);
+            uint32_t uIntraOff = uOffset - RT_OFFSETOF(VIRTIO_PCI_COMMON_CFG_T, uDriverFeatures);
             switch(pVirtio->uDriverFeaturesSelect)
             {
                 case 0:
                     memcpy(&pVirtio->uDriverFeatures, pv, cb);
-                    LogFunc(("Guest wrote uDriverFeatures(LO)[%d:%d]: %.*Rhxs\n",
-                              foff, foff + cb, cb, pv));
+                    LOG_ACCESSOR(uDriverFeatures);
                     break;
                 case 1:
                     memcpy(((char *)&pVirtio->uDriverFeatures) + sizeof(uint32_t), pv, cb);
-                    LogFunc(("Guest wrote uDriverFeatures(HI)[%d:%d]: %.*Rhxs\n",
-                              foff, foff + cb, cb, pv));
+                    uIntraOff += 4;
+                    LOG_ACCESSOR(uDriverFeatures);
                     break;
+                default:
+                    LogFunc(("Guest wrote uDriverFeatures with out of range selector (%d), returning 0\n",
+                         pVirtio->uDriverFeaturesSelect));
+                    return VERR_ACCESS_DENIED;
             }
         }
         else /* Guest READ pCommonCfg->udriverFeatures */
         {
-            uint32_t foff = uoff - RT_OFFSETOF(VIRTIO_PCI_COMMON_CFG_T, uDriverFeatures);
+            uint32_t uIntraOff = uOffset - RT_OFFSETOF(VIRTIO_PCI_COMMON_CFG_T, uDriverFeatures);
             switch(pVirtio->uDriverFeaturesSelect)
             {
@@ -686 +578 @@
                     val = pVirtio->uDriverFeatures & 0xffffffff;
                     memcpy((void *)pv, (const void *)&val, cb);
-                    LogFunc(("Guest read  uDriverFeatures(LO)[%d:%d]: %.*Rhxs\n",
-                              foff, foff + cb, cb, pv));
+                    LOG_ACCESSOR(uDriverFeatures);
                     break;
                 case 1:
                     val = (pVirtio->uDriverFeatures >> 32) & 0xffffffff;
+                    uIntraOff += 4;
                     memcpy((void *)pv, (const void *)&val, cb);
-                    LogFunc(("Guest read  uDriverFeatures(HI)[%d:%d]: %.*Rhxs\n",
-                              foff, foff + cb, cb, pv));
+                    LOG_ACCESSOR(uDriverFeatures);
                     break;
                 default:
-                    Log(("Guest read uDriverFeatures with out of range selector (%d), returning 0\n",
+                    LogFunc(("Guest read uDriverFeatures with out of range selector (%d), returning 0\n",
                          pVirtio->uDriverFeaturesSelect));
+                    return VERR_ACCESS_DENIED;
             }
         }
@@ -704 +596 @@
     {
         if (fWrite)
-            Log(("Guest attempted to write readonly virtio_pci_common_cfg.num_queues\n"));
+        {
+            LogFunc(("Guest attempted to write readonly virtio_pci_common_cfg.num_queues\n"));
+            return VERR_ACCESS_DENIED;
+        }
         else
         {
+            uint32_t uIntraOff = 0;
             *(uint16_t *)pv = MAX_QUEUES;
-            Log(("Guest read 0x%x from pVirtio->uNumQueues\n", MAX_QUEUES));
+            LOG_ACCESSOR(uNumQueues);
         }
     }
@@ -716 +612 @@
         {
             pVirtio->uDeviceStatus = *(uint8_t *)pv;
-            LogFunc(("Driver wrote uDeviceStatus:\n"));
-            logDeviceStatus(pVirtio->uDeviceStatus);
+            LogFunc(("Guest wrote uDeviceStatus ................ ("));
+            virtioLogDeviceStatus(pVirtio->uDeviceStatus);
+            Log((")\n"));
             if (pVirtio->uDeviceStatus == 0)
                 virtioResetDevice(pVirtio);
@@ -723 +620 @@
         else /* Guest READ pCommonCfg->uDeviceStatus */
         {
-            LogFunc(("Driver read uDeviceStatus:\n"));
+            LogFunc(("Guest read  uDeviceStatus ................ ("));
             *(uint32_t *)pv = pVirtio->uDeviceStatus;
-            logDeviceStatus(pVirtio->uDeviceStatus);
+            virtioLogDeviceStatus(pVirtio->uDeviceStatus);
+            Log((")\n"));
         }
     }
@@ -778 +676 @@
     else
     {
-        LogFunc(("Bad access by guest to virtio_pci_common_cfg: uoff=%d, cb=%d\n", uoff, cb));
-        rv = VERR_ACCESS_DENIED;
-    }
-    return rv;
+        LogFunc(("Bad access by guest to virtio_pci_common_cfg: uOffset=%d, cb=%d\n", uOffset, cb));
+        rc = VERR_ACCESS_DENIED;
+    }
+    return rc;
 }
 
@@ -1153 +1051 @@
 #endif
 
-#define CFGADDR2IDX(addr) ((uint64_t)addr - (uint64_t)&pVirtio->dev.abConfig)
 
     /* The following capability mapped via VirtIO 1.0: struct virtio_pci_cfg_cap (VIRTIO_PCI_CFG_CAP_T)
@@ -1161 +1058 @@
      * therefore does not contribute to the capabilities region (BAR) the other capabilities use.
      */
+#define CFGADDR2IDX(addr) ((uint64_t)addr - (uint64_t)&pVirtio->dev.abConfig)
+
     PVIRTIO_PCI_CAP_T pCfg;
 
@@ -1251 +1150 @@
 #endif /* IN_RING3 */
 
-#endif /* VBOX_DEVICE_STRUCT_TESTCASE */
-

trunk/src/VBox/Devices/VirtIO/Virtio_1_0.h

@@ -73 +73 @@
 #define VIRTIO_MSI_NO_VECTOR                0xffff
 
-typedef DECLCALLBACK(uint32_t) FNGETHOSTFEATURES(void *pvState);
-typedef FNGETHOSTFEATURES *PFNGETHOSTFEATURES;
-
-
 /** Most of the following definitions attempt to adhere to the names and
  *  and forms used by the VirtIO 1.0 specification to increase the maintainability
@@ -440 +436 @@
 void    vringSetNotification( PVIRTIOSTATE pVirtio, PVIRTQUEUE pVirtQueue, bool fEnabled);
 
-DECLINLINE(void) logDeviceStatus(uint8_t status)
-{
-    if (status & VIRTIO_STATUS_ACKNOWLEDGE)
-        Log(("                         ACKNOWLEDGE\n"));
-    if (status & VIRTIO_STATUS_DRIVER)
-        Log(("                         DRIVER\n"));
-    if (status & VIRTIO_STATUS_DRIVER_OK)
-        Log(("                         DRIVER_OK\n"));
-    if (status & VIRTIO_STATUS_FEATURES_OK)
-        Log(("                         FEATURES_OK\n"));
-    if (status & VIRTIO_STATUS_FAILED)
-        Log(("                         FAILED\n"));
-    if (status & VIRTIO_STATUS_DEVICE_NEEDS_RESET)
-        Log(("                         ACKNOWLEDGE\n"));
-    if (status == 0)
-        Log(("                         RESET\n"));
-    Log(("\n"));
-}
 
 /*  FROM Virtio 1.0 SPEC, NYI
@@ -477 +455 @@
 */
 
+
+
+/**
+ * Formats the logging of a memory-mapped I/O input or output value
+ *
+ * @param   pszFunc     - To avoid displaying this function's name via __FUNCTION__ or LogFunc()
+ * @param   pszMember   - Name of struct member
+ * @param   pv          - pointer to value
+ * @param   cb          - size of value
+ * @param   uOffset     - offset into member where value starts
+ * @param   fWrite      - True if write I/O
+ * @param   fHasIndex   - True if the member is indexed
+ * @param   idx         - The index if fHasIndex
+ */
+DECLINLINE(void) virtioLogMappedIoValue(const char *pszFunc, const char *pszMember, const void *pv, uint32_t cb,
+                        uint32_t uOffset, bool fWrite, bool fHasIndex, uint32_t idx)
+{
+
+#define FMTHEX(fmtout, v, cNybs) \
+    fmtout[cNybs] = '\0'; \
+    for (uint8_t i = 0; i < cNybs; i++) \
+        fmtout[(cNybs - i) -1] = "0123456789abcdef"[(val >> (i * 4)) & 0xf];
+
+#define MAX_STRING   64
+    char pszIdx[MAX_STRING] = { 0 };
+    char pszDepiction[MAX_STRING] = { 0 };
+    char pszFormattedVal[MAX_STRING] = { 0 };
+    if (fHasIndex)
+        RTStrPrintf(pszIdx, sizeof(pszIdx), "[%d]", idx);
+    if (cb == 1 || cb == 2 || cb == 4 || cb == 8)
+    {
+        /* manually padding with 0's instead of \b due to different impl of %x precision than printf() */
+        uint64_t val = 0;
+        memcpy((char *)&val, pv, cb);
+        FMTHEX(pszFormattedVal, val, cb * 2);
+        RTStrPrintf(pszDepiction, sizeof(pszDepiction), "%s%s[%d:%d]", pszMember, pszIdx, uOffset, uOffset + cb);
+        RTStrPrintf(pszDepiction, sizeof(pszDepiction), "%-30s", pszDepiction);
+        int first = 0;
+        for (uint8_t i = 0; i < sizeof(pszDepiction); i++)
+            if (pszDepiction[i] == ' ' && first++ != 0)
+                pszDepiction[i] = '.';
+        Log(("%s: Guest %s %s 0x%s\n", \
+                  pszFunc, fWrite ? "wrote" : "read ", pszDepiction, pszFormattedVal));
+    }
+    else /* odd number or oversized access, ... log inline hex-dump style */
+    {
+        Log(("%s: Guest %s %s%s[%d:%d]: %.*Rhxs\n", \
+              pszFunc, fWrite ? "wrote" : "read ", pszMember,
+              pszIdx, uOffset, uOffset + cb, cb, pv));
+    }
+}
+
+typedef DECLCALLBACK(uint32_t) FNGETHOSTFEATURES(void *pvState);
+typedef FNGETHOSTFEATURES *PFNGETHOSTFEATURES;
+
 DECLINLINE(uint16_t) vringReadAvail(PVIRTIOSTATE pState, PVIRTQUEUE pVirtQueue)
 {