[Qemu-devel] [PATCH qemu v10 12/14] vfio: Unregister IOMMU notifiers when container is destroyed

[Alexey Kardashevskiy <aik@ozlabs.ru>]

On systems with guest visible IOMMU, adding a new memory region onto
PCI bus calls vfio_listener_region_add() for every DMA window. This
installs a notifier for IOMMU memory regions. The notifier is supposed
to be removed by vfio_listener_region_del(), however in the case of mixed
PHB (emulated + VFIO devices) when last VFIO device is unplugged and
container gets destroyed, all existing DMA windows stay alive altogether
with the notifiers which are on the linked list which head was in
the destroyed container.

This unregisters IOMMU memory region notifier when a container is
destroyed.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
---
Changes:
v10:
* new to the patchset
---
 hw/vfio/common.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 89ef37b..8eacfd7 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -772,11 +772,19 @@ static void vfio_disconnect_container(VFIOGroup *group)
 
     if (QLIST_EMPTY(&container->group_list)) {
         VFIOAddressSpace *space = container->space;
+        VFIOGuestIOMMU *giommu, *tmp;
 
         if (container->iommu_data.release) {
             container->iommu_data.release(container);
         }
         QLIST_REMOVE(container, next);
+
+        QLIST_FOREACH_SAFE(giommu, &container->giommu_list, giommu_next, tmp) {
+            memory_region_unregister_iommu_notifier(&giommu->n);
+            QLIST_REMOVE(giommu, giommu_next);
+            g_free(giommu);
+        }
+
         trace_vfio_disconnect_container(container->fd);
         close(container->fd);
         g_free(container);
-- 
2.4.0.rc3.8.gfb3e7d5