On 2025/10/17 16:22, Zhenzhong Duan wrote:
Commit e46883204c38 ("vfio/migration: Block migration with vIOMMU")
introduces a migration blocker when vIOMMU is enabled, because we need
to calculate the IOVA ranges for device dirty tracking. But this is
unnecessary for iommu dirty tracking.
Limit the vfio_viommu_preset() check to those devices which use device
dirty tracking. This allows live migration with VFIO devices which use
iommu dirty tracking.
Introduce a helper vfio_device_dirty_pages_disabled() to facilicate it.
s/facilicate/facilitate/
Reviewed-by: Yi Liu <[email protected]>
Suggested-by: Jason Zeng <[email protected]>
Co-developed-by: Joao Martins <[email protected]>
Signed-off-by: Joao Martins <[email protected]>
Signed-off-by: Zhenzhong Duan <[email protected]>
Tested-by: Xudong Hao <[email protected]>
Tested-by: Giovannio Cabiddu <[email protected]>
---
include/hw/vfio/vfio-device.h | 10 ++++++++++
hw/vfio/container.c | 5 +----
hw/vfio/device.c | 6 ++++++
hw/vfio/migration.c | 6 +++---
4 files changed, 20 insertions(+), 7 deletions(-)
diff --git a/include/hw/vfio/vfio-device.h b/include/hw/vfio/vfio-device.h
index 7e9aed6d3c..feda521514 100644
--- a/include/hw/vfio/vfio-device.h
+++ b/include/hw/vfio/vfio-device.h
@@ -148,6 +148,16 @@ bool vfio_device_irq_set_signaling(VFIODevice *vbasedev,
int index, int subindex
void vfio_device_reset_handler(void *opaque);
bool vfio_device_is_mdev(VFIODevice *vbasedev);
+/**
+ * vfio_device_dirty_pages_disabled: Check if device dirty tracking will be
+ * used for a VFIO device
+ *
+ * @vbasedev: The VFIODevice to transform
+ *
+ * Return: true if either @vbasedev doesn't support device dirty tracking or
+ * is forcedly disabled from command line, otherwise false.
+ */
+bool vfio_device_dirty_pages_disabled(VFIODevice *vbasedev);
bool vfio_device_hiod_create_and_realize(VFIODevice *vbasedev,
const char *typename, Error **errp);
bool vfio_device_attach(char *name, VFIODevice *vbasedev,
diff --git a/hw/vfio/container.c b/hw/vfio/container.c
index 7706603c1c..8879da78c8 100644
--- a/hw/vfio/container.c
+++ b/hw/vfio/container.c
@@ -178,10 +178,7 @@ bool vfio_container_devices_dirty_tracking_is_supported(
VFIODevice *vbasedev;
QLIST_FOREACH(vbasedev, &bcontainer->device_list, container_next) {
- if (vbasedev->device_dirty_page_tracking == ON_OFF_AUTO_OFF) {
- return false;
- }
- if (!vbasedev->dirty_pages_supported) {
+ if (vfio_device_dirty_pages_disabled(vbasedev)) {
return false;
}
}
diff --git a/hw/vfio/device.c b/hw/vfio/device.c
index 64f8750389..837872387f 100644
--- a/hw/vfio/device.c
+++ b/hw/vfio/device.c
@@ -400,6 +400,12 @@ bool vfio_device_is_mdev(VFIODevice *vbasedev)
return subsys && (strcmp(subsys, "/sys/bus/mdev") == 0);
}
+bool vfio_device_dirty_pages_disabled(VFIODevice *vbasedev)
+{
+ return (!vbasedev->dirty_pages_supported ||
+ vbasedev->device_dirty_page_tracking == ON_OFF_AUTO_OFF);
+}
+
bool vfio_device_hiod_create_and_realize(VFIODevice *vbasedev,
const char *typename, Error **errp)
{
diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c
index 1106ca7857..1093857a34 100644
--- a/hw/vfio/migration.c
+++ b/hw/vfio/migration.c
@@ -1213,8 +1213,7 @@ bool vfio_migration_realize(VFIODevice *vbasedev, Error
**errp)
return !vfio_block_migration(vbasedev, err, errp);
}
- if ((!vbasedev->dirty_pages_supported ||
- vbasedev->device_dirty_page_tracking == ON_OFF_AUTO_OFF) &&
+ if (vfio_device_dirty_pages_disabled(vbasedev) &&
!vbasedev->iommu_dirty_tracking) {
if (vbasedev->enable_migration == ON_OFF_AUTO_AUTO) {
error_setg(&err,
@@ -1232,7 +1231,8 @@ bool vfio_migration_realize(VFIODevice *vbasedev, Error
**errp)
goto out_deinit;
}
- if (vfio_viommu_preset(vbasedev)) {
+ if (!vfio_device_dirty_pages_disabled(vbasedev) &&
+ vfio_viommu_preset(vbasedev)) {
error_setg(&err, "%s: Migration is currently not supported "
"with vIOMMU enabled", vbasedev->name);
goto add_blocker;
