diff mbox series

[RFC,2/2] vfio: listener unregister before unset container

Message ID 20180119084219.31187-3-peterx@redhat.com
State New
Headers show
Series memory/vfio: notify region_del() when unregister listeners | expand

Commit Message

Peter Xu Jan. 19, 2018, 8:42 a.m. UTC
After previous patch, listener unregister will need the container to be
alive.  Let's move this unregister phase to be before unset container,
since that operation will free the backend container in kernel, then
we'll get these after previous patch:

qemu-system-x86_64: VFIO_UNMAP_DMA: -22
qemu-system-x86_64: vfio_dma_unmap(0x559bf53a4590, 0x0, 0xa0000) = -22 (Invalid argument)

Signed-off-by: Peter Xu <peterx@redhat.com>
---
 hw/vfio/common.c | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)
diff mbox series

Patch

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index b77be3a8b3..76cf28d462 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -1161,19 +1161,27 @@  static void vfio_disconnect_container(VFIOGroup *group)
 {
     VFIOContainer *container = group->container;
 
+    QLIST_REMOVE(group, container_next);
+    group->container = NULL;
+
+    /*
+     * Explicitly release the listener first before unset container,
+     * since unset may destroy the backend container if it's the last
+     * group.
+     */
+    if (QLIST_EMPTY(&container->group_list)) {
+        vfio_listener_release(container);
+    }
+
     if (ioctl(group->fd, VFIO_GROUP_UNSET_CONTAINER, &container->fd)) {
         error_report("vfio: error disconnecting group %d from container",
                      group->groupid);
     }
 
-    QLIST_REMOVE(group, container_next);
-    group->container = NULL;
-
     if (QLIST_EMPTY(&container->group_list)) {
         VFIOAddressSpace *space = container->space;
         VFIOGuestIOMMU *giommu, *tmp;
 
-        vfio_listener_release(container);
         QLIST_REMOVE(container, next);
 
         QLIST_FOREACH_SAFE(giommu, &container->giommu_list, giommu_next, tmp) {