3 files changed, 42 insertions, 7 deletions
diff --git a/include/hw/i386/intel_iommu.h b/include/hw/i386/intel_iommu.h
index 46d973e629..89dcbc5e1e 100644
--- a/include/hw/i386/intel_iommu.h
+++ b/include/hw/i386/intel_iommu.h
@@ -109,7 +109,43 @@ struct VTDAddressSpace {
     QLIST_ENTRY(VTDAddressSpace) next;
     /* Superset of notifier flags that this address space has */
     IOMMUNotifierFlag notifier_flags;
-    IOVATree *iova_tree;          /* Traces mapped IOVA ranges */
+    /*
+     * @iova_tree traces mapped IOVA ranges.
+     *
+     * The tree is not needed if no MAP notifier is registered with current
+     * VTD address space, because all guest invalidate commands can be
+     * directly passed to the IOMMU UNMAP notifiers without any further
+     * reshuffling.
+     *
+     * The tree OTOH is required for MAP typed iommu notifiers for a few
+     * reasons.
+     *
+     * Firstly, there's no way to identify whether an PSI (Page Selective
+     * Invalidations) or DSI (Domain Selective Invalidations) event is an
+     * MAP or UNMAP event within the message itself.  Without having prior
+     * knowledge of existing state vIOMMU doesn't know whether it should
+     * notify MAP or UNMAP for a PSI message it received when caching mode
+     * is enabled (for MAP notifiers).
+     *
+     * Secondly, PSI messages received from guest driver can be enlarged in
+     * range, covers but not limited to what the guest driver wanted to
+     * invalidate.  When the range to invalidates gets bigger than the
+     * limit of a PSI message, it can even become a DSI which will
+     * invalidate the whole domain.  If the vIOMMU directly notifies the
+     * registered device with the unmodified range, it may confuse the
+     * registered drivers (e.g. vfio-pci) on either:
+     *
+     *   (1) Trying to map the same region more than once (for
+     *       VFIO_IOMMU_MAP_DMA, -EEXIST will trigger), or,
+     *
+     *   (2) Trying to UNMAP a range that is still partially mapped.
+     *
+     * That accuracy is not required for UNMAP-only notifiers, but it is a
+     * must-to-have for notifiers registered with MAP events, because the
+     * vIOMMU needs to make sure the shadow page table is always in sync
+     * with the guest IOMMU pgtables for a device.
+     */
+    IOVATree *iova_tree;
 };
 
 struct VTDIOTLBEntry {
diff --git a/include/hw/i386/microvm.h b/include/hw/i386/microvm.h
index fad97a891d..e8af61f194 100644
--- a/include/hw/i386/microvm.h
+++ b/include/hw/i386/microvm.h
@@ -50,8 +50,9 @@
  */
 
 /* Platform virtio definitions */
-#define VIRTIO_MMIO_BASE      0xfeb00000
-#define VIRTIO_CMDLINE_MAXLEN 64
+#define VIRTIO_MMIO_BASE                0xfeb00000
+#define VIRTIO_CMDLINE_MAXLEN           64
+#define VIRTIO_CMDLINE_TOTAL_MAX_LEN    ((VIRTIO_CMDLINE_MAXLEN + 1) * 16)
 
 #define GED_MMIO_BASE         0xfea00000
 #define GED_MMIO_BASE_MEMHP   (GED_MMIO_BASE + 0x100)
diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
index 88a120bc23..66e3d059ef 100644
--- a/include/hw/i386/pc.h
+++ b/include/hw/i386/pc.h
@@ -9,7 +9,6 @@
 #include "hw/block/flash.h"
 #include "hw/i386/x86.h"
 
-#include "hw/acpi/acpi_dev_interface.h"
 #include "hw/hotplug.h"
 #include "qom/object.h"
 #include "hw/i386/sgx-epc.h"
@@ -193,9 +192,8 @@ bool pc_system_ovmf_table_find(const char *entry, uint8_t **data,
 void pc_system_parse_ovmf_flash(uint8_t *flash_ptr, size_t flash_size);
 
 /* hw/i386/acpi-common.c */
-void pc_madt_cpu_entry(AcpiDeviceIf *adev, int uid,
-                       const CPUArchIdList *apic_ids, GArray *entry,
-                       bool force_enabled);
+void pc_madt_cpu_entry(int uid, const CPUArchIdList *apic_ids,
+                       GArray *entry, bool force_enabled);
 
 /* sgx.c */
 void pc_machine_init_sgx_epc(PCMachineState *pcms);