diff --git a/hypervisor/dm/vpci/pci_pt.c b/hypervisor/dm/vpci/pci_pt.c
index 2a9eea54d..b2d728778 100644
--- a/hypervisor/dm/vpci/pci_pt.c
+++ b/hypervisor/dm/vpci/pci_pt.c
@@ -53,19 +53,11 @@ static inline struct msix_table_entry *get_msix_table_entry(const struct pci_vde
  * @pre vdev != NULL
  * @pre vdev->pdev != NULL
  */
-void write_vmsix_cap_reg(struct pci_vdev *vdev, uint32_t offset, uint32_t bytes, uint32_t val)
+void write_pt_vmsix_cap_reg(struct pci_vdev *vdev, uint32_t offset, uint32_t bytes, uint32_t val)
 {
-	static const uint8_t msix_ro_mask[12U] = {
-		0xffU, 0xffU, 0xffU, 0x3fU,	/* Only Function Mask and MSI-X Enable writable */
-		0xffU, 0xffU, 0xffU, 0xffU,
-		0xffU, 0xffU, 0xffU, 0xffU };
-	uint32_t msgctrl, old, ro_mask = ~0U;
-
-	(void)memcpy_s((void *)&ro_mask, bytes, (void *)&msix_ro_mask[offset - vdev->msix.capoff], bytes);
-	if (ro_mask != ~0U) {
-		old = pci_vdev_read_vcfg(vdev, offset, bytes);
-		pci_vdev_write_vcfg(vdev, offset, bytes, (old & ro_mask) | (val & ~ro_mask));
+	uint32_t msgctrl;
 
+	if (write_vmsix_cap_reg(vdev, offset, bytes, val)) {
 		msgctrl = pci_vdev_read_vcfg(vdev, vdev->msix.capoff + PCIR_MSIX_CTRL, 2U);
 		/* If MSI Enable is being set, make sure INTxDIS bit is set */
 		if ((msgctrl & PCIM_MSIXCTRL_MSIX_ENABLE) != 0U) {
@@ -131,105 +123,26 @@ static void remap_one_vmsix_entry(const struct pci_vdev *vdev, uint32_t index)
 
 }
 
-/**
- * @pre vdev != NULL
- * @pre mmio != NULL
- */
-static void rw_vmsix_table(struct pci_vdev *vdev, struct mmio_request *mmio, uint32_t offset)
-{
-	struct msix_table_entry *entry;
-	uint32_t entry_offset, table_offset, index;
-
-	/* Find out which entry it's accessing */
-	table_offset = offset - vdev->msix.table_offset;
-	index = table_offset / MSIX_TABLE_ENTRY_SIZE;
-
-	if (index < vdev->msix.table_count) {
-		entry = &vdev->msix.table_entries[index];
-		entry_offset = table_offset % MSIX_TABLE_ENTRY_SIZE;
-
-		if (mmio->direction == REQUEST_READ) {
-			(void)memcpy_s(&mmio->value, (size_t)mmio->size,
-					(void *)entry + entry_offset, (size_t)mmio->size);
-		} else {
-			/* Only DWORD and QWORD are permitted */
-			if ((mmio->size == 4U) || (mmio->size == 8U)) {
-				/* Write to pci_vdev */
-				(void)memcpy_s((void *)entry + entry_offset, (size_t)mmio->size,
-						&mmio->value, (size_t)mmio->size);
-				if (vdev->msix.is_vmsix_on_msi) {
-					remap_one_vmsix_entry_on_msi(vdev, index);
-				} else {
-					remap_one_vmsix_entry(vdev, index);
-				}
-			} else {
-				pr_err("%s, Only DWORD and QWORD are permitted", __func__);
-			}
-
-		}
-	} else {
-		pr_err("%s, invalid arguments %lx - %lx", __func__, mmio->value, mmio->address);
-	}
-
-}
-
-
 /**
  * @pre io_req != NULL
- * @pre handler_private_data != NULL
+ * @pre priv_data != NULL
  */
-static int32_t vmsix_handle_table_mmio_access(struct io_request *io_req, void *handler_private_data)
+static int32_t pt_vmsix_handle_table_mmio_access(struct io_request *io_req, void *priv_data)
 {
 	struct mmio_request *mmio = &io_req->reqs.mmio;
 	struct pci_vdev *vdev;
+	uint32_t index;
 	int32_t ret = 0;
-	uint64_t offset;
-	void *hva;
 
-	vdev = (struct pci_vdev *)handler_private_data;
-	/* This device has not be assigned to other OS */
+	vdev = (struct pci_vdev *)priv_data;
 	if (vdev->user == vdev) {
-		offset = mmio->address - vdev->msix.mmio_gpa;
+		index = rw_vmsix_table(vdev, io_req);
 
-		if (msixtable_access(vdev, (uint32_t)offset)) {
-			rw_vmsix_table(vdev, mmio, (uint32_t)offset);
-		} else if (vdev->msix.is_vmsix_on_msi) {
-			/* According to PCI spec, PBA is read-only.
-			 * Don't emulate PBA according to the device status, just return 0.
-			 */
-			if (mmio->direction == REQUEST_READ) {
-				mmio->value = 0UL;
+		if ((mmio->direction == REQUEST_WRITE) && (index < vdev->msix.table_count)) {
+			if (vdev->msix.is_vmsix_on_msi) {
+				remap_one_vmsix_entry_on_msi(vdev, index);
 			} else {
-				ret = -EINVAL;
-			}
-		} else {
-			hva = hpa2hva(vdev->msix.mmio_hpa + offset);
-
-			/* Only DWORD and QWORD are permitted */
-			if ((mmio->size == 4U) || (mmio->size == 8U)) {
-				if (hva != NULL) {
-					stac();
-					/* MSI-X PBA and Capability Table could be in the same range */
-					if (mmio->direction == REQUEST_READ) {
-						/* mmio->size is either 4U or 8U */
-						if (mmio->size == 4U) {
-							mmio->value = (uint64_t)mmio_read32((const void *)hva);
-						} else {
-							mmio->value = mmio_read64((const void *)hva);
-						}
-					} else {
-						/* mmio->size is either 4U or 8U */
-						if (mmio->size == 4U) {
-							mmio_write32((uint32_t)(mmio->value), (void *)hva);
-						} else {
-							mmio_write64(mmio->value, (void *)hva);
-						}
-					}
-					clac();
-				}
-			} else {
-				pr_err("%s, Only DWORD and QWORD are permitted", __func__);
-				ret = -EINVAL;
+				remap_one_vmsix_entry(vdev, index);
 			}
 		}
 	} else {
@@ -284,7 +197,7 @@ void vdev_pt_map_msix(struct pci_vdev *vdev, bool hold_lock)
 		addr_hi = addr_lo + (msix->table_count * MSIX_TABLE_ENTRY_SIZE);
 		addr_lo = round_page_down(addr_lo);
 		addr_hi = round_page_up(addr_hi);
-		register_mmio_emulation_handler(vm, vmsix_handle_table_mmio_access,
+		register_mmio_emulation_handler(vm, pt_vmsix_handle_table_mmio_access,
 				addr_lo, addr_hi, vdev, hold_lock);
 		ept_del_mr(vm, (uint64_t *)vm->arch_vm.nworld_eptp, addr_lo, addr_hi - addr_lo);
 		msix->mmio_gpa = vbar->base_gpa;
@@ -537,7 +450,7 @@ static void init_bars(struct pci_vdev *vdev, bool is_sriov_bar)
  * @pre vdev != NULL
  * @pre vdev->pdev != NULL
  */
-void init_vmsix(struct pci_vdev *vdev)
+void init_vmsix_pt(struct pci_vdev *vdev)
 {
 	struct pci_pdev *pdev = vdev->pdev;
 
@@ -557,7 +470,7 @@ void init_vmsix(struct pci_vdev *vdev)
  * @pre vdev != NULL
  * @pre vdev->vpci != NULL
  */
-void deinit_vmsix(struct pci_vdev *vdev)
+void deinit_vmsix_pt(struct pci_vdev *vdev)
 {
 	if (has_msix_cap(vdev)) {
 		if (vdev->msix.table_count != 0U) {
diff --git a/hypervisor/dm/vpci/vmsi.c b/hypervisor/dm/vpci/vmsi.c
index 3ca17540c..0f9c0c974 100644
--- a/hypervisor/dm/vpci/vmsi.c
+++ b/hypervisor/dm/vpci/vmsi.c
@@ -95,15 +95,6 @@ static void remap_vmsi(const struct pci_vdev *vdev)
 	}
 }
 
-/**
- * @pre vdev != NULL
- */
-void read_vmsi_cap_reg(const struct pci_vdev *vdev, uint32_t offset, uint32_t bytes, uint32_t *val)
-{
-	/* For PIO access, we emulate Capability Structures only */
-	*val = pci_vdev_read_vcfg(vdev, offset, bytes);
-}
-
 /**
  * @brief Writing MSI Capability Structure
  *
diff --git a/hypervisor/dm/vpci/vmsix.c b/hypervisor/dm/vpci/vmsix.c
index 106664a58..3d876fb1c 100644
--- a/hypervisor/dm/vpci/vmsix.c
+++ b/hypervisor/dm/vpci/vmsix.c
@@ -36,10 +36,76 @@
 #include "vpci_priv.h"
 
 /**
+ * @brief Writing MSI-X Capability Structure
+ *
  * @pre vdev != NULL
+ * @pre vdev->pdev != NULL
  */
-void read_vmsix_cap_reg(const struct pci_vdev *vdev, uint32_t offset, uint32_t bytes, uint32_t *val)
+bool write_vmsix_cap_reg(struct pci_vdev *vdev, uint32_t offset, uint32_t bytes, uint32_t val)
 {
-	/* For PIO access, we emulate Capability Structures only */
-	*val = pci_vdev_read_vcfg(vdev, offset, bytes);
+	static const uint8_t msix_ro_mask[12U] = {
+		0xffU, 0xffU, 0xffU, 0x3fU,	/* Only Function Mask and MSI-X Enable writable */
+		0xffU, 0xffU, 0xffU, 0xffU,
+		0xffU, 0xffU, 0xffU, 0xffU };
+	bool is_written = false;
+	uint32_t old, ro_mask = ~0U;
+
+	(void)memcpy_s((void *)&ro_mask, bytes, (void *)&msix_ro_mask[offset - vdev->msix.capoff], bytes);
+	if (ro_mask != ~0U) {
+		old = pci_vdev_read_vcfg(vdev, offset, bytes);
+		pci_vdev_write_vcfg(vdev, offset, bytes, (old & ro_mask) | (val & ~ro_mask));
+		is_written = true;
+	}
+
+	return is_written;
+}
+
+/**
+ * @pre vdev != NULL
+ * @pre io_req != NULL
+ * @pre mmio->address >= vdev->msix.mmio_gpa
+ */
+uint32_t rw_vmsix_table(struct pci_vdev *vdev, struct io_request *io_req)
+{
+	struct mmio_request *mmio = &io_req->reqs.mmio;
+	struct msix_table_entry *entry;
+	uint32_t entry_offset, table_offset, index = CONFIG_MAX_MSIX_TABLE_NUM;
+	uint64_t offset;
+
+	/* Must be full DWORD or full QWORD aligned. */
+	if ((mmio->size == 4U) || (mmio->size == 8U)) {
+		offset = mmio->address - vdev->msix.mmio_gpa;
+		if (msixtable_access(vdev, (uint32_t)offset)) {
+
+			table_offset = (uint32_t)(offset - vdev->msix.table_offset);
+			index = table_offset / MSIX_TABLE_ENTRY_SIZE;
+
+			entry = &vdev->msix.table_entries[index];
+			entry_offset = table_offset % MSIX_TABLE_ENTRY_SIZE;
+
+			if (mmio->direction == REQUEST_READ) {
+				(void)memcpy_s(&mmio->value, (size_t)mmio->size,
+					(void *)entry + entry_offset, (size_t)mmio->size);
+			} else {
+				(void)memcpy_s((void *)entry + entry_offset, (size_t)mmio->size,
+					&mmio->value, (size_t)mmio->size);
+			}
+		} else if (mmio->direction == REQUEST_READ) {
+			mmio->value = 0UL;
+		}
+	} else {
+		pr_err("%s, Only DWORD and QWORD are permitted", __func__);
+	}
+
+	return index;
+}
+
+/**
+ * @pre io_req != NULL
+ * @pre priv_data != NULL
+ */
+int32_t vmsix_handle_table_mmio_access(struct io_request *io_req, void *priv_data)
+{
+	(void)rw_vmsix_table((struct pci_vdev *)priv_data, io_req);
+	return 0;
 }
diff --git a/hypervisor/dm/vpci/vpci.c b/hypervisor/dm/vpci/vpci.c
index 03b8dbec9..069d54fda 100644
--- a/hypervisor/dm/vpci/vpci.c
+++ b/hypervisor/dm/vpci/vpci.c
@@ -360,12 +360,12 @@ static void vpci_init_pt_dev(struct pci_vdev *vdev)
 	vdev->user = vdev;
 
 	/*
-	 * Here init_vdev_pt() needs to be called after init_vmsix() for the following reason:
+	 * Here init_vdev_pt() needs to be called after init_vmsix_pt() for the following reason:
 	 * init_vdev_pt() will indirectly call has_msix_cap(), which
-	 * requires init_vmsix() to be called first.
+	 * requires init_vmsix_pt() to be called first.
 	 */
 	init_vmsi(vdev);
-	init_vmsix(vdev);
+	init_vmsix_pt(vdev);
 	init_vsriov(vdev);
 	init_vdev_pt(vdev, false);
 
@@ -376,7 +376,7 @@ static void vpci_deinit_pt_dev(struct pci_vdev *vdev)
 {
 	deinit_vdev_pt(vdev);
 	remove_vdev_pt_iommu_domain(vdev);
-	deinit_vmsix(vdev);
+	deinit_vmsix_pt(vdev);
 	deinit_vmsi(vdev);
 
 	vdev->user = NULL;
@@ -486,7 +486,7 @@ static int32_t write_pt_dev_cfg(struct pci_vdev *vdev, uint32_t offset,
 		if (vdev->msix.is_vmsix_on_msi) {
 			write_vmsix_cap_reg_on_msi(vdev, offset, bytes, val);
 		} else {
-			write_vmsix_cap_reg(vdev, offset, bytes, val);
+			write_pt_vmsix_cap_reg(vdev, offset, bytes, val);
 		}
 	} else if (sriovcap_access(vdev, offset)) {
 		write_sriov_cap_reg(vdev, offset, bytes, val);
@@ -511,10 +511,8 @@ static int32_t read_pt_dev_cfg(const struct pci_vdev *vdev, uint32_t offset,
 
 	if (cfg_header_access(offset)) {
 		read_cfg_header(vdev, offset, bytes, val);
-	} else if (msicap_access(vdev, offset)) {
-		read_vmsi_cap_reg(vdev, offset, bytes, val);
-	} else if (msixcap_access(vdev, offset)) {
-		read_vmsix_cap_reg(vdev, offset, bytes, val);
+	} else if (msicap_access(vdev, offset) || msixcap_access(vdev, offset)) {
+		*val = pci_vdev_read_vcfg(vdev, offset, bytes);
 	} else if (sriovcap_access(vdev, offset)) {
 		read_sriov_cap_reg(vdev, offset, bytes, val);
 	} else {
diff --git a/hypervisor/dm/vpci/vpci_priv.h b/hypervisor/dm/vpci/vpci_priv.h
index 490f3f64d..e91f94294 100644
--- a/hypervisor/dm/vpci/vpci_priv.h
+++ b/hypervisor/dm/vpci/vpci_priv.h
@@ -140,14 +140,14 @@ void vdev_pt_write_vbar(struct pci_vdev *vdev, uint32_t idx, uint32_t val);
 void vdev_pt_map_msix(struct pci_vdev *vdev, bool hold_lock);
 
 void init_vmsi(struct pci_vdev *vdev);
-void read_vmsi_cap_reg(const struct pci_vdev *vdev, uint32_t offset, uint32_t bytes, uint32_t *val);
 void write_vmsi_cap_reg(struct pci_vdev *vdev, uint32_t offset, uint32_t bytes, uint32_t val);
 void deinit_vmsi(const struct pci_vdev *vdev);
 
-void init_vmsix(struct pci_vdev *vdev);
-void read_vmsix_cap_reg(const struct pci_vdev *vdev, uint32_t offset, uint32_t bytes, uint32_t *val);
-void write_vmsix_cap_reg(struct pci_vdev *vdev, uint32_t offset, uint32_t bytes, uint32_t val);
-void deinit_vmsix(struct pci_vdev *vdev);
+void init_vmsix_pt(struct pci_vdev *vdev);
+bool write_vmsix_cap_reg(struct pci_vdev *vdev, uint32_t offset, uint32_t bytes, uint32_t val);
+void write_pt_vmsix_cap_reg(struct pci_vdev *vdev, uint32_t offset, uint32_t bytes, uint32_t val);
+uint32_t rw_vmsix_table(struct pci_vdev *vdev, struct io_request *io_req);
+void deinit_vmsix_pt(struct pci_vdev *vdev);
 
 void init_vmsix_on_msi(struct pci_vdev *vdev);
 void write_vmsix_cap_reg_on_msi(struct pci_vdev *vdev, uint32_t offset, uint32_t bytes, uint32_t val);