* [PULL 1/3] tests/qtest/libqos: Add Intel IOMMU helper library
2026-04-29 14:32 [PULL 0/3] Qtest patches for 2026-04-29 Fabiano Rosas
@ 2026-04-29 14:32 ` Fabiano Rosas
2026-04-29 14:32 ` [PULL 2/3] tests/qtest: Add Intel IOMMU bare-metal test Fabiano Rosas
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: Fabiano Rosas @ 2026-04-29 14:32 UTC (permalink / raw)
To: qemu-devel; +Cc: Fengyuan Yu, Chao Liu, Tao Tang
From: Fengyuan Yu <15fengyuan@gmail.com>
Introduce a libqos helper module for Intel IOMMU (VT-d) bare-metal
testing via iommu-testdev. The helper provides routines to:
- Build Legacy-mode structures: Root Entry Tables, Context Entry Tables,
and 4-level page tables for 48-bit address translation
- Build Scalable-mode structures: Scalable Context Entries, PASID
Directory Entries, PASID Table Entries, and 4-level page tables for
both second-level and first-level translation
- Program VT-d registers (Root Table Address, Invalidation Queue,
Fault Event MSI, Global Command) following the VT-d specification,
with GSTS read-back verification for each step
- Execute DMA translations through iommu-testdev and verify results
by reading back guest memory
The module supports all major VT-d translation modes through the
QVTDTransMode enum:
- Legacy pass-through
- Legacy translated with 4-level paging
- Scalable pass-through
- Scalable Second-Level Translation
- Scalable First-Level Translation
Reviewed-by: Chao Liu <chao.liu.zevorn@gmail.com>
Signed-off-by: Fengyuan Yu <15fengyuan@gmail.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Tao Tang <tangtao1634@phytium.com.cn>
Link: https://lore.kernel.org/qemu-devel/c4f7bf5d7985891a2db291193669ebe15dd2ba15.1774421649.git.15fengyuan@gmail.com
Signed-off-by: Fabiano Rosas <farosas@suse.de>
---
MAINTAINERS | 1 +
tests/qtest/libqos/meson.build | 3 +
tests/qtest/libqos/qos-intel-iommu.c | 454 +++++++++++++++++++++++++++
tests/qtest/libqos/qos-intel-iommu.h | 185 +++++++++++
4 files changed, 643 insertions(+)
create mode 100644 tests/qtest/libqos/qos-intel-iommu.c
create mode 100644 tests/qtest/libqos/qos-intel-iommu.h
diff --git a/MAINTAINERS b/MAINTAINERS
index 49f9bce818..3887dda851 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3597,6 +3597,7 @@ S: Maintained
F: tests/qtest/libqos/qos-iommu*
F: tests/qtest/libqos/qos-smmuv3*
F: tests/qtest/libqos/qos-riscv-iommu*
+F: tests/qtest/libqos/qos-intel-iommu*
Device Fuzzing
M: Alexander Bulekov <alxndr@bu.edu>
diff --git a/tests/qtest/libqos/meson.build b/tests/qtest/libqos/meson.build
index 4a69acad0d..96f2fc48b4 100644
--- a/tests/qtest/libqos/meson.build
+++ b/tests/qtest/libqos/meson.build
@@ -73,6 +73,9 @@ endif
if config_all_devices.has_key('CONFIG_RISCV_IOMMU')
libqos_srcs += files('riscv-iommu.c', 'qos-riscv-iommu.c')
endif
+if config_all_devices.has_key('CONFIG_VTD')
+ libqos_srcs += files('qos-intel-iommu.c')
+endif
if config_all_devices.has_key('CONFIG_TPCI200')
libqos_srcs += files('tpci200.c')
endif
diff --git a/tests/qtest/libqos/qos-intel-iommu.c b/tests/qtest/libqos/qos-intel-iommu.c
new file mode 100644
index 0000000000..f8ca4c871b
--- /dev/null
+++ b/tests/qtest/libqos/qos-intel-iommu.c
@@ -0,0 +1,454 @@
+/*
+ * QOS Intel IOMMU (VT-d) Module Implementation
+ *
+ * This module provides Intel IOMMU-specific helper functions for libqos tests.
+ *
+ * Copyright (c) 2026 Fengyuan Yu <15fengyuan@gmail.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "hw/i386/intel_iommu_internal.h"
+#include "tests/qtest/libqos/pci.h"
+#include "qos-iommu-testdev.h"
+#include "qos-intel-iommu.h"
+
+#define QVTD_AW_48BIT_ENCODING 2
+
+uint32_t qvtd_expected_dma_result(QVTDTestContext *ctx)
+{
+ return ctx->config.expected_result;
+}
+
+uint32_t qvtd_build_dma_attrs(void)
+{
+ /*
+ * VT-d obtains the Requester ID (Source ID) from PCI bus/devfn routing
+ * via pci_device_iommu_address_space(), not from DMA attributes.
+ *
+ * For scalable mode, iommu-testdev does not set MemTxAttrs.pid,
+ * so the device's VTDAddressSpace has pasid=PCI_NO_PASID.
+ * vtd_do_iommu_translate() remaps PCI_NO_PASID to PASID_0
+ * when root_scalable is set, which matches the PASID=0 entry
+ * we configure in qvtd_build_pasid_table_entry().
+ */
+ return 0;
+}
+
+static void qvtd_build_root_entry(QTestState *qts, uint8_t bus,
+ uint64_t context_table_ptr,
+ QVTDTransMode mode)
+{
+ uint64_t root_entry_addr = QVTD_ROOT_TABLE_BASE +
+ (bus * sizeof(VTDRootEntry));
+ uint64_t lo, hi;
+
+ if (qvtd_is_scalable(mode)) {
+ /*
+ * Scalable-mode Root Entry (Section 9.2):
+ * lo = Lower Context Table Pointer + LP (Lower Present)
+ * hi = Upper Context Table Pointer + UP (Upper Present)
+ *
+ * Lower table covers devfn 0-127, Upper covers devfn 128-255.
+ * Only lower half is needed for test device (devfn < 128).
+ */
+ lo = (context_table_ptr & VTD_ROOT_ENTRY_CTP) | VTD_ROOT_ENTRY_P;
+ hi = 0; /* UP=0: upper context table not present */
+ } else {
+ /*
+ * Legacy Root Entry (Section 9.1):
+ * lo = Context Table Pointer + Present
+ * hi = Reserved
+ */
+ lo = (context_table_ptr & VTD_ROOT_ENTRY_CTP) | VTD_ROOT_ENTRY_P;
+ hi = 0;
+ }
+
+ qtest_writeq(qts, root_entry_addr, lo);
+ qtest_writeq(qts, root_entry_addr + 8, hi);
+}
+
+static void qvtd_build_context_entry(QTestState *qts, uint16_t sid,
+ QVTDTransMode mode, uint64_t ssptptr)
+{
+ uint8_t devfn = sid & 0xff;
+ uint64_t context_entry_addr = QVTD_CONTEXT_TABLE_BASE +
+ (devfn * VTD_CTX_ENTRY_LEGACY_SIZE);
+ uint64_t lo, hi;
+
+ if (mode == QVTD_TM_LEGACY_PT) {
+ /*
+ * Pass-through mode (Section 9.3):
+ * lo: P + FPD(=0, fault enabled) + TT(=Pass-through)
+ * hi: DID + AW
+ */
+ lo = VTD_CONTEXT_ENTRY_P | VTD_CONTEXT_TT_PASS_THROUGH;
+ hi = ((uint64_t)QVTD_DOMAIN_ID << 8) | QVTD_AW_48BIT_ENCODING;
+ } else {
+ /*
+ * Translated mode (Section 9.3):
+ * lo: P + FPD(=0, fault enabled) + TT(=Multi-level) + SSPTPTR
+ * hi: DID + AW(=48-bit, 4-level)
+ */
+ lo = VTD_CONTEXT_ENTRY_P | VTD_CONTEXT_TT_MULTI_LEVEL |
+ (ssptptr & VTD_CONTEXT_ENTRY_SSPTPTR);
+ hi = ((uint64_t)QVTD_DOMAIN_ID << 8) | QVTD_AW_48BIT_ENCODING;
+ }
+
+ qtest_writeq(qts, context_entry_addr, lo);
+ qtest_writeq(qts, context_entry_addr + 8, hi);
+}
+
+static void qvtd_build_scalable_context_entry(QTestState *qts, uint16_t sid)
+{
+ uint8_t devfn = sid & 0xff;
+ uint64_t ce_addr = QVTD_CONTEXT_TABLE_BASE +
+ (devfn * VTD_CTX_ENTRY_SCALABLE_SIZE);
+
+ /*
+ * Scalable-Mode Context Entry (Section 9.4), 32 bytes = 4 qwords:
+ *
+ * val[0]: P + FPD(=0) + DTE(=0) + PASIDE(=0) + PRE(=0) + HPTE(=0)
+ * + EPTR(=0) + PDTS(=0) + PASIDDIRPTR
+ * val[1]: RID_PASID(=0) + PDTTE(=0) + PRE(=0) + RID_CG(=0)
+ * val[2]: Reserved (must be 0)
+ * val[3]: Reserved (must be 0)
+ */
+ qtest_writeq(qts, ce_addr,
+ (QVTD_PASID_DIR_BASE & VTD_PASID_DIR_BASE_ADDR_MASK) |
+ VTD_CONTEXT_ENTRY_P);
+ qtest_writeq(qts, ce_addr + 8, 0);
+ qtest_writeq(qts, ce_addr + 16, 0);
+ qtest_writeq(qts, ce_addr + 24, 0);
+}
+
+static void qvtd_build_pasid_dir_entry(QTestState *qts)
+{
+ uint64_t addr = QVTD_PASID_DIR_BASE +
+ VTD_PASID_DIR_INDEX(0) * VTD_PASID_DIR_ENTRY_SIZE;
+
+ /*
+ * PASID Directory Entry (Section 9.5):
+ * P + FPD(=0, fault enabled) + SMPTBLPTR
+ */
+ qtest_writeq(qts, addr,
+ (QVTD_PASID_TABLE_BASE & VTD_PASID_TABLE_BASE_ADDR_MASK) |
+ VTD_PASID_ENTRY_P);
+}
+
+static void qvtd_build_pasid_table_entry(QTestState *qts, QVTDTransMode mode,
+ uint64_t ptptr)
+{
+ uint64_t addr = QVTD_PASID_TABLE_BASE +
+ VTD_PASID_TABLE_INDEX(0) * VTD_PASID_ENTRY_SIZE;
+ uint64_t val0, val1, val2;
+
+ /*
+ * Scalable-Mode PASID Table Entry (Section 9.6), 64 bytes = 8 qwords:
+ *
+ * val[0]: P + FPD(=0) + AW + PGTT + SSADE(=0) + SSPTPTR
+ * val[1]: DID + PWSNP(=0) + PGSNP(=0)
+ * + CD(=0) + EMTE(=0) + PAT(=0): Memory Type,
+ * all Reserved(0) since QEMU ECAP.MTS=0
+ * val[2]: SRE(=0) + FSPM(=0, 4-level) + WPE(=0) + IGN + EAFE(=0) + FSPTPTR
+ * val[3]: Reserved (must be 0)
+ * val[4]: HPT fields, Reserved(0) since QEMU ECAP.HPTS=0
+ * val[5]: HPT fields, Reserved(0) since QEMU ECAP.HPTS=0
+ * val[6]: Reserved (must be 0)
+ * val[7]: Reserved (must be 0)
+ */
+ switch (mode) {
+ case QVTD_TM_SCALABLE_PT:
+ val0 = VTD_PASID_ENTRY_P |
+ ((uint64_t)VTD_SM_PASID_ENTRY_PT << 6);
+ val1 = (uint64_t)QVTD_DOMAIN_ID;
+ val2 = 0;
+ break;
+ case QVTD_TM_SCALABLE_SLT:
+ val0 = VTD_PASID_ENTRY_P |
+ ((uint64_t)VTD_SM_PASID_ENTRY_SST << 6) |
+ ((uint64_t)QVTD_AW_48BIT_ENCODING << 2) |
+ (ptptr & VTD_SM_PASID_ENTRY_SSPTPTR);
+ val1 = (uint64_t)QVTD_DOMAIN_ID;
+ val2 = 0;
+ break;
+ case QVTD_TM_SCALABLE_FLT:
+ /*
+ * val[2] fields for FLT (Section 9.6):
+ * SRE(=0, user-level DMA only) + FSPM(=0, 4-level) +
+ * WPE(=0, no supervisor write-protect) + IGN + EAFE(=0) + FSPTPTR
+ */
+ val0 = VTD_PASID_ENTRY_P |
+ ((uint64_t)VTD_SM_PASID_ENTRY_FST << 6);
+ val1 = (uint64_t)QVTD_DOMAIN_ID;
+ val2 = ptptr & QVTD_SM_PASID_ENTRY_FSPTPTR;
+ break;
+ default:
+ g_assert_not_reached();
+ }
+
+ qtest_writeq(qts, addr, val0);
+ qtest_writeq(qts, addr + 8, val1);
+ qtest_writeq(qts, addr + 16, val2);
+ qtest_writeq(qts, addr + 24, 0);
+ qtest_writeq(qts, addr + 32, 0);
+ qtest_writeq(qts, addr + 40, 0);
+ qtest_writeq(qts, addr + 48, 0);
+ qtest_writeq(qts, addr + 56, 0);
+}
+
+/*
+ * VT-d second-level paging helpers.
+ * 4-level, 48-bit address space, 9 bits per level index.
+ */
+static uint32_t qvtd_get_table_index(uint64_t iova, int level)
+{
+ int shift = VTD_PAGE_SHIFT + VTD_LEVEL_BITS * (level - 1);
+
+ return (iova >> shift) & ((1u << VTD_LEVEL_BITS) - 1);
+}
+
+static uint64_t qvtd_get_table_addr(uint64_t base, int level, uint64_t iova)
+{
+ return base + (qvtd_get_table_index(iova, level) * QVTD_PTE_SIZE);
+}
+
+static uint64_t qvtd_get_pte_attrs(void)
+{
+ /* Second-level: R/W in every paging entry (Section 3.7.1) */
+ return VTD_SS_R | VTD_SS_W;
+}
+
+static uint64_t qvtd_get_fl_pte_attrs(bool is_leaf)
+{
+ /* First-level: x86 page table format (VT-d spec Section 9.9) */
+ uint64_t attrs = VTD_FS_P | VTD_FS_RW | VTD_FS_US | VTD_FS_A;
+
+ if (is_leaf) {
+ attrs |= VTD_FS_D;
+ }
+ return attrs;
+}
+
+void qvtd_setup_translation_tables(QTestState *qts, uint64_t iova,
+ QVTDTransMode mode)
+{
+ bool is_fl = (mode == QVTD_TM_SCALABLE_FLT);
+ uint64_t non_leaf_attrs, leaf_attrs;
+
+ if (is_fl) {
+ non_leaf_attrs = qvtd_get_fl_pte_attrs(false);
+ leaf_attrs = qvtd_get_fl_pte_attrs(true);
+ } else {
+ /* Second-level: all levels use identical R/W attrs (spec 3.7.1) */
+ non_leaf_attrs = qvtd_get_pte_attrs();
+ leaf_attrs = non_leaf_attrs;
+ }
+
+ g_test_message("Page table setup: IOVA=0x%" PRIx64
+ " PA=0x%" PRIx64 " %s",
+ (uint64_t)iova, (uint64_t)QVTD_PT_VAL,
+ is_fl ? "first-level" : "second-level");
+
+ /* PML4 (L4) -> PDPT (L3) -> PD (L2) -> PT (L1) -> PA */
+ qtest_writeq(qts, qvtd_get_table_addr(QVTD_PT_L4_BASE, 4, iova),
+ QVTD_PT_L3_BASE | non_leaf_attrs);
+ qtest_writeq(qts, qvtd_get_table_addr(QVTD_PT_L3_BASE, 3, iova),
+ QVTD_PT_L2_BASE | non_leaf_attrs);
+ qtest_writeq(qts, qvtd_get_table_addr(QVTD_PT_L2_BASE, 2, iova),
+ QVTD_PT_L1_BASE | non_leaf_attrs);
+ qtest_writeq(qts, qvtd_get_table_addr(QVTD_PT_L1_BASE, 1, iova),
+ (QVTD_PT_VAL & VTD_PAGE_MASK_4K) | leaf_attrs);
+}
+
+void qvtd_program_regs(QTestState *qts, uint64_t iommu_base,
+ QVTDTransMode mode)
+{
+ uint32_t gcmd = 0;
+ uint64_t rtaddr = QVTD_ROOT_TABLE_BASE;
+
+ /* Set SMT bit for scalable mode (VT-d spec Section 9.1) */
+ if (qvtd_is_scalable(mode)) {
+ rtaddr |= VTD_RTADDR_SMT;
+ }
+
+ /* Set Root Table Address */
+ qtest_writeq(qts, iommu_base + DMAR_RTADDR_REG, rtaddr);
+
+ /* Set Root Table Pointer and verify */
+ gcmd |= VTD_GCMD_SRTP;
+ qtest_writel(qts, iommu_base + DMAR_GCMD_REG, gcmd);
+ g_assert(qtest_readl(qts, iommu_base + DMAR_GSTS_REG) & VTD_GSTS_RTPS);
+
+ /* Setup Invalidation Queue */
+ qtest_writeq(qts, iommu_base + DMAR_IQA_REG,
+ QVTD_IQ_BASE | QVTD_IQ_QS);
+ qtest_writeq(qts, iommu_base + DMAR_IQH_REG, 0);
+ qtest_writeq(qts, iommu_base + DMAR_IQT_REG, 0);
+
+ /* Enable Queued Invalidation and verify */
+ gcmd |= VTD_GCMD_QIE;
+ qtest_writel(qts, iommu_base + DMAR_GCMD_REG, gcmd);
+ g_assert(qtest_readl(qts, iommu_base + DMAR_GSTS_REG) & VTD_GSTS_QIES);
+
+ /* Setup Fault Event MSI */
+ qtest_writel(qts, iommu_base + DMAR_FECTL_REG, 0x0);
+ qtest_writel(qts, iommu_base + DMAR_FEDATA_REG, QVTD_FAULT_IRQ_DATA);
+ qtest_writel(qts, iommu_base + DMAR_FEADDR_REG, QVTD_FAULT_IRQ_ADDR);
+
+ /* Enable translation and verify */
+ gcmd |= VTD_GCMD_TE;
+ qtest_writel(qts, iommu_base + DMAR_GCMD_REG, gcmd);
+ g_assert(qtest_readl(qts, iommu_base + DMAR_GSTS_REG) & VTD_GSTS_TES);
+}
+
+uint32_t qvtd_build_translation(QTestState *qts, QVTDTransMode mode,
+ uint16_t sid)
+{
+ uint8_t bus = (sid >> 8) & 0xff;
+
+ g_test_message("Build translation: IOVA=0x%" PRIx64 " PA=0x%" PRIx64
+ " mode=%d",
+ (uint64_t)QVTD_IOVA, (uint64_t)QVTD_PT_VAL, mode);
+
+ /* Clear IOMMU structure regions to avoid stale entries */
+ qtest_memset(qts, QVTD_ROOT_TABLE_BASE, 0, 0x1000);
+ qtest_memset(qts, QVTD_PT_L4_BASE, 0, 0x4000);
+
+ if (qvtd_is_scalable(mode)) {
+ /* Scalable: 32B context entries need 8KB */
+ qtest_memset(qts, QVTD_CONTEXT_TABLE_BASE, 0, 0x2000);
+ qtest_memset(qts, QVTD_PASID_DIR_BASE, 0, 0x1000);
+ qtest_memset(qts, QVTD_PASID_TABLE_BASE, 0, 0x1000);
+ } else {
+ qtest_memset(qts, QVTD_CONTEXT_TABLE_BASE, 0, 0x1000);
+ }
+
+ qvtd_build_root_entry(qts, bus, QVTD_CONTEXT_TABLE_BASE, mode);
+
+ if (qvtd_is_scalable(mode)) {
+ /* Scalable path: context -> PASID dir -> PASID entry -> page tables */
+ qvtd_build_scalable_context_entry(qts, sid);
+ qvtd_build_pasid_dir_entry(qts);
+
+ if (mode == QVTD_TM_SCALABLE_PT) {
+ qvtd_build_pasid_table_entry(qts, mode, 0);
+ } else {
+ qvtd_setup_translation_tables(qts, QVTD_IOVA, mode);
+ qvtd_build_pasid_table_entry(qts, mode, QVTD_PT_L4_BASE);
+ }
+ } else {
+ /* Legacy path */
+ if (mode == QVTD_TM_LEGACY_PT) {
+ qvtd_build_context_entry(qts, sid, mode, 0);
+ } else {
+ qvtd_setup_translation_tables(qts, QVTD_IOVA, mode);
+ qvtd_build_context_entry(qts, sid, mode, QVTD_PT_L4_BASE);
+ }
+ }
+
+ return 0;
+}
+
+uint32_t qvtd_setup_and_enable_translation(QVTDTestContext *ctx)
+{
+ uint32_t build_result;
+
+ /* Build translation structures first */
+ build_result = qvtd_build_translation(ctx->qts, ctx->config.trans_mode,
+ ctx->sid);
+ if (build_result != 0) {
+ g_test_message("Build failed: mode=%u sid=%u status=0x%x",
+ ctx->config.trans_mode, ctx->sid, build_result);
+ ctx->trans_status = build_result;
+ return ctx->trans_status;
+ }
+
+ /* Program IOMMU registers (sets root table pointer, enables translation) */
+ qvtd_program_regs(ctx->qts, ctx->iommu_base, ctx->config.trans_mode);
+
+ ctx->trans_status = 0;
+ return ctx->trans_status;
+}
+
+static bool qvtd_validate_test_result(QVTDTestContext *ctx)
+{
+ uint32_t expected = qvtd_expected_dma_result(ctx);
+
+ g_test_message("-> Validating result: expected=0x%x actual=0x%x",
+ expected, ctx->dma_result);
+ return (ctx->dma_result == expected);
+}
+
+static uint32_t qvtd_single_translation_setup(void *opaque)
+{
+ return qvtd_setup_and_enable_translation(opaque);
+}
+
+static uint32_t qvtd_single_translation_attrs(void *opaque)
+{
+ return qvtd_build_dma_attrs();
+}
+
+static bool qvtd_single_translation_validate(void *opaque)
+{
+ return qvtd_validate_test_result(opaque);
+}
+
+static void qvtd_single_translation_report(void *opaque, uint32_t dma_result)
+{
+ QVTDTestContext *ctx = opaque;
+
+ if (dma_result != 0) {
+ g_test_message("DMA failed: mode=%u result=0x%x",
+ ctx->config.trans_mode, dma_result);
+ } else {
+ g_test_message("-> DMA succeeded: mode=%u",
+ ctx->config.trans_mode);
+ }
+}
+
+void qvtd_run_translation_case(QTestState *qts, QPCIDevice *dev,
+ QPCIBar bar, uint64_t iommu_base,
+ const QVTDTestConfig *cfg)
+{
+ QVTDTestContext ctx = {
+ .qts = qts,
+ .dev = dev,
+ .bar = bar,
+ .iommu_base = iommu_base,
+ .config = *cfg,
+ .sid = dev->devfn,
+ };
+
+ QOSIOMMUTestdevDmaCfg dma = {
+ .dev = dev,
+ .bar = bar,
+ .iova = QVTD_IOVA,
+ .gpa = cfg->dma_gpa,
+ .len = cfg->dma_len,
+ };
+
+ qtest_memset(qts, cfg->dma_gpa, 0x00, cfg->dma_len);
+ qos_iommu_testdev_single_translation(&dma, &ctx,
+ qvtd_single_translation_setup,
+ qvtd_single_translation_attrs,
+ qvtd_single_translation_validate,
+ qvtd_single_translation_report,
+ &ctx.dma_result);
+
+ if (ctx.dma_result == 0 && ctx.config.expected_result == 0) {
+ g_autofree uint8_t *buf = NULL;
+
+ buf = g_malloc(ctx.config.dma_len);
+ qtest_memread(ctx.qts, ctx.config.dma_gpa, buf, ctx.config.dma_len);
+
+ for (int i = 0; i < ctx.config.dma_len; i++) {
+ uint8_t expected;
+
+ expected = (ITD_DMA_WRITE_VAL >> ((i % 4) * 8)) & 0xff;
+ g_assert_cmpuint(buf[i], ==, expected);
+ }
+ }
+}
diff --git a/tests/qtest/libqos/qos-intel-iommu.h b/tests/qtest/libqos/qos-intel-iommu.h
new file mode 100644
index 0000000000..c6cacc5c3f
--- /dev/null
+++ b/tests/qtest/libqos/qos-intel-iommu.h
@@ -0,0 +1,185 @@
+/*
+ * QOS Intel IOMMU (VT-d) Module
+ *
+ * This module provides Intel IOMMU-specific helper functions for libqos tests,
+ * encapsulating VT-d setup, assertion, and cleanup operations.
+ *
+ * Copyright (c) 2026 Fengyuan Yu <15fengyuan@gmail.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#ifndef QTEST_LIBQOS_INTEL_IOMMU_H
+#define QTEST_LIBQOS_INTEL_IOMMU_H
+
+#include "hw/misc/iommu-testdev.h"
+#include "hw/i386/intel_iommu_internal.h"
+
+/*
+ * Guest memory layout for IOMMU structures.
+ * All structures are placed in guest physical memory inside the 512MB RAM.
+ * Using 256MB mark (0x10000000) as base to ensure all structures fit in RAM.
+ */
+#define QVTD_MEM_BASE 0x10000000ULL
+
+/* Root Entry Table: 256 entries * 16 bytes = 4KB */
+#define QVTD_ROOT_TABLE_BASE (QVTD_MEM_BASE + 0x00000000)
+
+/* Context Entry Table: 256 entries, 16B (legacy) or 32B (scalable) per entry */
+#define QVTD_CONTEXT_TABLE_BASE (QVTD_MEM_BASE + 0x00001000)
+
+/* Page Tables: 4-level hierarchy for 48-bit address translation */
+#define QVTD_PT_L4_BASE (QVTD_MEM_BASE + 0x00010000) /* PML4 */
+#define QVTD_PT_L3_BASE (QVTD_MEM_BASE + 0x00011000) /* PDPT */
+#define QVTD_PT_L2_BASE (QVTD_MEM_BASE + 0x00012000) /* PD */
+#define QVTD_PT_L1_BASE (QVTD_MEM_BASE + 0x00013000) /* PT */
+
+/*
+ * Invalidation Queue.
+ * IQA_REG bits[2:0] = QS, entries = 1 << (QS + 8), each entry 16 bytes.
+ */
+#define QVTD_IQ_BASE (QVTD_MEM_BASE + 0x00020000)
+#define QVTD_IQ_QS 0 /* QS=0 → 256 entries */
+
+/*
+ * Fault Event MSI configuration.
+ */
+#define QVTD_FAULT_IRQ_ADDR 0xfee00000 /* APIC base */
+#define QVTD_FAULT_IRQ_DATA 0x0
+
+/* Scalable mode PASID structures */
+#define QVTD_PASID_DIR_BASE (QVTD_MEM_BASE + 0x00030000)
+#define QVTD_PASID_TABLE_BASE (QVTD_MEM_BASE + 0x00031000)
+
+/* Page table entry size (8 bytes per PTE) */
+#define QVTD_PTE_SIZE sizeof(uint64_t)
+
+/* FSPTPTR mask: same as VTD_SM_PASID_ENTRY_SSPTPTR, bits[63:12] */
+#define QVTD_SM_PASID_ENTRY_FSPTPTR VTD_SM_PASID_ENTRY_SSPTPTR
+
+/* Default Domain ID for single-domain tests */
+#define QVTD_DOMAIN_ID 0
+
+/* Test IOVA and target physical address */
+#define QVTD_IOVA 0x0000000010200567ull
+#define QVTD_PT_VAL (QVTD_MEM_BASE + 0x00100000)
+
+/*
+ * Translation modes supported by Intel IOMMU
+ */
+typedef enum QVTDTransMode {
+ QVTD_TM_LEGACY_PT, /* Legacy pass-through mode */
+ QVTD_TM_LEGACY_TRANS, /* Legacy translated mode (4-level paging) */
+ QVTD_TM_SCALABLE_PT, /* Scalable pass-through mode */
+ QVTD_TM_SCALABLE_SLT, /* Scalable Second Level Translation */
+ QVTD_TM_SCALABLE_FLT, /* Scalable First Level Translation */
+} QVTDTransMode;
+
+static inline bool qvtd_is_scalable(QVTDTransMode mode)
+{
+ return mode == QVTD_TM_SCALABLE_PT ||
+ mode == QVTD_TM_SCALABLE_SLT ||
+ mode == QVTD_TM_SCALABLE_FLT;
+}
+
+typedef struct QVTDTestConfig {
+ QVTDTransMode trans_mode; /* Translation mode */
+ uint64_t dma_gpa; /* GPA for readback validation */
+ uint32_t dma_len; /* DMA length for testing */
+ uint32_t expected_result; /* Expected DMA result */
+} QVTDTestConfig;
+
+typedef struct QVTDTestContext {
+ QTestState *qts; /* QTest state handle */
+ QPCIDevice *dev; /* PCI device handle */
+ QPCIBar bar; /* PCI BAR for MMIO access */
+ QVTDTestConfig config; /* Test configuration */
+ uint64_t iommu_base; /* Intel IOMMU base address */
+ uint32_t trans_status; /* Translation configuration status */
+ uint32_t dma_result; /* DMA operation result */
+ uint16_t sid; /* Source ID (bus:devfn) */
+} QVTDTestContext;
+
+/*
+ * qvtd_setup_and_enable_translation - Complete translation setup and enable
+ *
+ * @ctx: Test context containing configuration and device handles
+ *
+ * Returns: Translation status (0 = success, non-zero = error)
+ *
+ * This function performs the complete translation setup sequence:
+ * 1. Builds VT-d structures (root/context entry, page tables)
+ * 2. Programs IOMMU registers and enables translation
+ * 3. Returns configuration status
+ */
+uint32_t qvtd_setup_and_enable_translation(QVTDTestContext *ctx);
+
+/*
+ * qvtd_build_translation - Build Intel IOMMU translation structures
+ *
+ * @qts: QTest state handle
+ * @mode: Translation mode (pass-through or translated)
+ * @sid: Source ID (bus:devfn)
+ *
+ * Returns: Build status (0 = success, non-zero = error)
+ *
+ * Constructs all necessary VT-d translation structures in guest memory:
+ * - Root Entry for the device's bus
+ * - Context Entry for the device
+ * - Complete 4-level page table hierarchy (if translated mode)
+ */
+uint32_t qvtd_build_translation(QTestState *qts, QVTDTransMode mode,
+ uint16_t sid);
+
+/*
+ * qvtd_program_regs - Program Intel IOMMU registers and enable translation
+ *
+ * @qts: QTest state handle
+ * @iommu_base: IOMMU base address
+ * @mode: Translation mode (scalable modes set RTADDR SMT bit)
+ *
+ * Programs IOMMU registers with the following sequence:
+ * 1. Set root table pointer (SRTP), with SMT bit for scalable mode
+ * 2. Setup invalidation queue (QIE)
+ * 3. Configure fault event MSI
+ * 4. Enable translation (TE)
+ *
+ * Each step verifies completion via GSTS register read-back.
+ */
+void qvtd_program_regs(QTestState *qts, uint64_t iommu_base,
+ QVTDTransMode mode);
+
+/*
+ * qvtd_setup_translation_tables - Setup complete VT-d page table hierarchy
+ *
+ * @qts: QTest state handle
+ * @iova: Input Virtual Address to translate
+ * @mode: Translation mode
+ *
+ * This builds the 4-level page table structure for translating
+ * the given IOVA to PA through Intel VT-d. The structure is:
+ * - PML4 (Level 4): IOVA bits [47:39]
+ * - PDPT (Level 3): IOVA bits [38:30]
+ * - PD (Level 2): IOVA bits [29:21]
+ * - PT (Level 1): IOVA bits [20:12]
+ * - Page offset: IOVA bits [11:0]
+ *
+ * The function writes all necessary Page Table Entries (PTEs) to guest
+ * memory using qtest_writeq(), setting up the complete translation path
+ * that the VT-d hardware will traverse during DMA operations.
+ */
+void qvtd_setup_translation_tables(QTestState *qts, uint64_t iova,
+ QVTDTransMode mode);
+
+/* Calculate expected DMA result */
+uint32_t qvtd_expected_dma_result(QVTDTestContext *ctx);
+
+/* Build DMA attributes for Intel VT-d */
+uint32_t qvtd_build_dma_attrs(void);
+
+/* High-level test execution helpers */
+void qvtd_run_translation_case(QTestState *qts, QPCIDevice *dev,
+ QPCIBar bar, uint64_t iommu_base,
+ const QVTDTestConfig *cfg);
+
+#endif /* QTEST_LIBQOS_INTEL_IOMMU_H */
--
2.51.0
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PULL 2/3] tests/qtest: Add Intel IOMMU bare-metal test
2026-04-29 14:32 [PULL 0/3] Qtest patches for 2026-04-29 Fabiano Rosas
2026-04-29 14:32 ` [PULL 1/3] tests/qtest/libqos: Add Intel IOMMU helper library Fabiano Rosas
@ 2026-04-29 14:32 ` Fabiano Rosas
2026-04-29 14:32 ` [PULL 3/3] tests/qtest: Make qtest_get_arch() cleverer Fabiano Rosas
2026-04-30 17:35 ` [PULL 0/3] Qtest patches for 2026-04-29 Stefan Hajnoczi
3 siblings, 0 replies; 5+ messages in thread
From: Fabiano Rosas @ 2026-04-29 14:32 UTC (permalink / raw)
To: qemu-devel; +Cc: Fengyuan Yu, Chao Liu, Tao Tang
From: Fengyuan Yu <15fengyuan@gmail.com>
Add a qtest suite for the Intel IOMMU (VT-d) device on the Q35 machine.
The test exercises both Legacy and Scalable translation modes using
iommu-testdev and the qos-intel-iommu helpers, without requiring any
guest kernel or firmware.
The test validates:
- Legacy-mode Root Entry Table and Context Entry Table configuration
- Scalable-mode Context Entry, PASID Directory, and PASID Table setup
- Legacy-mode 4-level page table walks for 48-bit address translation
- Scalable-mode second-level and first-level 4-level page table walks
- Pass-through mode in both Legacy and Scalable modes
- DMA transaction execution with memory content verification
Reviewed-by: Chao Liu <chao.liu.zevorn@gmail.com>
Signed-off-by: Fengyuan Yu <15fengyuan@gmail.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Tao Tang <tangtao1634@phytium.com.cn>
Link: https://lore.kernel.org/qemu-devel/ce3c44f3b07734a4f0ee43f55b21c856034af1b1.1774421649.git.15fengyuan@gmail.com
Signed-off-by: Fabiano Rosas <farosas@suse.de>
---
MAINTAINERS | 1 +
tests/qtest/iommu-intel-test.c | 216 +++++++++++++++++++++++++++++++++
tests/qtest/meson.build | 2 +
3 files changed, 219 insertions(+)
create mode 100644 tests/qtest/iommu-intel-test.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 3887dda851..b570c43673 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4010,6 +4010,7 @@ F: hw/i386/intel_iommu_accel.*
F: include/hw/i386/intel_iommu.h
F: tests/functional/x86_64/test_intel_iommu.py
F: tests/qtest/intel-iommu-test.c
+F: tests/qtest/iommu-intel-test.c
AMD-Vi Emulation
M: Alejandro Jimenez <alejandro.j.jimenez@oracle.com>
diff --git a/tests/qtest/iommu-intel-test.c b/tests/qtest/iommu-intel-test.c
new file mode 100644
index 0000000000..a52c45e298
--- /dev/null
+++ b/tests/qtest/iommu-intel-test.c
@@ -0,0 +1,216 @@
+/*
+ * QTest for Intel IOMMU (VT-d) with iommu-testdev
+ *
+ * This QTest file is used to test the Intel IOMMU with iommu-testdev so that
+ * we can test VT-d without any guest kernel or firmware.
+ *
+ * Copyright (c) 2026 Fengyuan Yu <15fengyuan@gmail.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "libqtest.h"
+#include "libqos/pci.h"
+#include "libqos/pci-pc.h"
+#include "hw/i386/intel_iommu_internal.h"
+#include "hw/misc/iommu-testdev.h"
+#include "libqos/qos-intel-iommu.h"
+
+#define DMA_LEN 4
+
+static uint64_t intel_iommu_expected_gpa(uint64_t iova)
+{
+ return (QVTD_PT_VAL & VTD_PAGE_MASK_4K) + (iova & 0xfff);
+}
+
+static void save_fn(QPCIDevice *dev, int devfn, void *data)
+{
+ QPCIDevice **pdev = (QPCIDevice **) data;
+
+ *pdev = dev;
+}
+
+static QPCIDevice *setup_qtest_pci_device(QTestState *qts, QPCIBus **pcibus,
+ QPCIBar *bar)
+{
+ QPCIDevice *dev = NULL;
+
+ *pcibus = qpci_new_pc(qts, NULL);
+ g_assert(*pcibus != NULL);
+
+ qpci_device_foreach(*pcibus, IOMMU_TESTDEV_VENDOR_ID,
+ IOMMU_TESTDEV_DEVICE_ID, save_fn, &dev);
+
+ g_assert(dev);
+ qpci_device_enable(dev);
+ *bar = qpci_iomap(dev, 0, NULL);
+ g_assert_false(bar->is_io);
+
+ return dev;
+}
+
+static const char *qvtd_iommu_args(QVTDTransMode mode)
+{
+ switch (mode) {
+ case QVTD_TM_SCALABLE_FLT:
+ return "-device intel-iommu,x-scalable-mode=on,x-flts=on ";
+ case QVTD_TM_SCALABLE_PT:
+ case QVTD_TM_SCALABLE_SLT:
+ return "-device intel-iommu,x-scalable-mode=on ";
+ default:
+ return "-device intel-iommu ";
+ }
+}
+
+static bool qvtd_check_caps(QTestState *qts, QVTDTransMode mode)
+{
+ uint64_t ecap = qtest_readq(qts,
+ Q35_HOST_BRIDGE_IOMMU_ADDR + DMAR_ECAP_REG);
+
+ /* All scalable modes require SMTS */
+ if (qvtd_is_scalable(mode) && !(ecap & VTD_ECAP_SMTS)) {
+ g_test_skip("ECAP.SMTS not supported");
+ return false;
+ }
+
+ switch (mode) {
+ case QVTD_TM_SCALABLE_PT:
+ if (!(ecap & VTD_ECAP_PT)) {
+ g_test_skip("ECAP.PT not supported");
+ return false;
+ }
+ break;
+ case QVTD_TM_SCALABLE_SLT:
+ if (!(ecap & VTD_ECAP_SSTS)) {
+ g_test_skip("ECAP.SSTS not supported");
+ return false;
+ }
+ break;
+ case QVTD_TM_SCALABLE_FLT:
+ if (!(ecap & VTD_ECAP_FSTS)) {
+ g_test_skip("ECAP.FSTS not supported");
+ return false;
+ }
+ break;
+ default:
+ break;
+ }
+
+ return true;
+}
+
+static void run_intel_iommu_translation(const QVTDTestConfig *cfg)
+{
+ QTestState *qts;
+ QPCIBus *pcibus;
+ QPCIDevice *dev;
+ QPCIBar bar;
+
+ if (!qtest_has_machine("q35")) {
+ g_test_skip("q35 machine not available");
+ return;
+ }
+
+ /* Initialize QEMU environment for Intel IOMMU testing */
+ qts = qtest_initf("-machine q35 -smp 1 -m 512 -net none "
+ "%s -device iommu-testdev",
+ qvtd_iommu_args(cfg->trans_mode));
+
+ /* Check CAP/ECAP capabilities for required translation mode */
+ if (!qvtd_check_caps(qts, cfg->trans_mode)) {
+ qtest_quit(qts);
+ return;
+ }
+
+ /* Setup and configure IOMMU-testdev PCI device */
+ dev = setup_qtest_pci_device(qts, &pcibus, &bar);
+ g_assert(dev);
+
+ g_test_message("### Intel IOMMU translation mode=%d ###", cfg->trans_mode);
+ qvtd_run_translation_case(qts, dev, bar, Q35_HOST_BRIDGE_IOMMU_ADDR, cfg);
+ g_free(dev);
+ qpci_free_pc(pcibus);
+ qtest_quit(qts);
+}
+
+static void test_intel_iommu_legacy_pt(void)
+{
+ QVTDTestConfig cfg = {
+ .trans_mode = QVTD_TM_LEGACY_PT,
+ .dma_gpa = QVTD_IOVA, /* pass-through: GPA == IOVA */
+ .dma_len = DMA_LEN,
+ .expected_result = 0,
+ };
+
+ run_intel_iommu_translation(&cfg);
+}
+
+static void test_intel_iommu_legacy_trans(void)
+{
+ QVTDTestConfig cfg = {
+ .trans_mode = QVTD_TM_LEGACY_TRANS,
+ .dma_gpa = intel_iommu_expected_gpa(QVTD_IOVA),
+ .dma_len = DMA_LEN,
+ .expected_result = 0,
+ };
+
+ run_intel_iommu_translation(&cfg);
+}
+
+static void test_intel_iommu_scalable_pt(void)
+{
+ QVTDTestConfig cfg = {
+ .trans_mode = QVTD_TM_SCALABLE_PT,
+ .dma_gpa = QVTD_IOVA, /* pass-through: GPA == IOVA */
+ .dma_len = DMA_LEN,
+ .expected_result = 0,
+ };
+
+ run_intel_iommu_translation(&cfg);
+}
+
+static void test_intel_iommu_scalable_slt(void)
+{
+ QVTDTestConfig cfg = {
+ .trans_mode = QVTD_TM_SCALABLE_SLT,
+ .dma_gpa = intel_iommu_expected_gpa(QVTD_IOVA),
+ .dma_len = DMA_LEN,
+ .expected_result = 0,
+ };
+
+ run_intel_iommu_translation(&cfg);
+}
+
+static void test_intel_iommu_scalable_flt(void)
+{
+ QVTDTestConfig cfg = {
+ .trans_mode = QVTD_TM_SCALABLE_FLT,
+ .dma_gpa = intel_iommu_expected_gpa(QVTD_IOVA),
+ .dma_len = DMA_LEN,
+ .expected_result = 0,
+ };
+
+ run_intel_iommu_translation(&cfg);
+}
+
+int main(int argc, char **argv)
+{
+ g_test_init(&argc, &argv, NULL);
+
+ /* Legacy mode tests */
+ qtest_add_func("/iommu-testdev/intel/legacy-pt",
+ test_intel_iommu_legacy_pt);
+ qtest_add_func("/iommu-testdev/intel/legacy-trans",
+ test_intel_iommu_legacy_trans);
+
+ /* Scalable mode tests */
+ qtest_add_func("/iommu-testdev/intel/scalable-pt",
+ test_intel_iommu_scalable_pt);
+ qtest_add_func("/iommu-testdev/intel/scalable-slt",
+ test_intel_iommu_scalable_slt);
+ qtest_add_func("/iommu-testdev/intel/scalable-flt",
+ test_intel_iommu_scalable_flt);
+
+ return g_test_run();
+}
diff --git a/tests/qtest/meson.build b/tests/qtest/meson.build
index b735f55fc4..43f83ffd3a 100644
--- a/tests/qtest/meson.build
+++ b/tests/qtest/meson.build
@@ -96,6 +96,8 @@ qtests_i386 = \
(config_all_devices.has_key('CONFIG_SDHCI_PCI') ? ['fuzz-sdcard-test'] : []) + \
(config_all_devices.has_key('CONFIG_ESP_PCI') ? ['am53c974-test'] : []) + \
(config_all_devices.has_key('CONFIG_VTD') ? ['intel-iommu-test'] : []) + \
+ (config_all_devices.has_key('CONFIG_VTD') and
+ config_all_devices.has_key('CONFIG_IOMMU_TESTDEV') ? ['iommu-intel-test'] : []) + \
(host_os != 'windows' and \
config_all_devices.has_key('CONFIG_ACPI_ERST') ? ['erst-test'] : []) + \
(config_all_devices.has_key('CONFIG_PCIE_PORT') and \
--
2.51.0
^ permalink raw reply related [flat|nested] 5+ messages in thread