@@ -1072,6 +1072,12 @@ static void device_set_realized(Object *obj, bool value, Error **errp)
goto post_realize_fail;
}
+ /* always re-initialize since we clean up in device_unparent() instead
+ * of unrealize()
+ */
+ g_free(dev->canonical_path);
+ dev->canonical_path = object_get_canonical_path(OBJECT(dev));
+
if (qdev_get_vmsd(dev)) {
vmstate_register_with_alias_id(dev, -1, qdev_get_vmsd(dev), dev,
dev->instance_id_alias,
@@ -1125,6 +1131,7 @@ child_realize_fail:
}
post_realize_fail:
+ g_free(dev->canonical_path);
if (dc->unrealize) {
dc->unrealize(dev, NULL);
}
@@ -1248,10 +1255,12 @@ static void device_unparent(Object *obj)
/* Only send event if the device had been completely realized */
if (dev->pending_deleted_event) {
- gchar *path = object_get_canonical_path(OBJECT(dev));
+ g_assert(dev->canonical_path);
- qapi_event_send_device_deleted(!!dev->id, dev->id, path, &error_abort);
- g_free(path);
+ qapi_event_send_device_deleted(!!dev->id, dev->id, dev->canonical_path,
+ &error_abort);
+ g_free(dev->canonical_path);
+ dev->canonical_path = NULL;
}
}
@@ -153,6 +153,7 @@ struct DeviceState {
/*< public >*/
const char *id;
+ char *canonical_path;
bool realized;
bool pending_deleted_event;
QemuOpts *opts;
device_unparent(dev, ...) is called when a device is unparented, either directly, or as a result of a parent device being finalized, and handles some final cleanup for the device. Part of this includes emiting a DEVICE_DELETED QMP event to notify management, which includes the device's path in the composition tree as provided by object_get_canonical_path(). object_get_canonical_path() assumes the device is still connected to the machine/root container, and will assert otherwise, but in some situations this isn't the case: If the parent is finalized as a result of object_unparent(), it will still be attached to the composition tree at the time any children are unparented as a result of that same call to object_unparent(). However, in some cases, object_unparent() will complete without finalizing the parent device, due to lingering references that won't be released till some time later. One such example is if the parent has MemoryRegion children (which take a ref on their parent), who in turn have AddressSpace's (which take a ref on their regions), since those AddressSpaces get cleaned up asynchronously by the RCU thread. In this case qdev:device_unparent() may be called for a child Device that no longer has a path to the root/machine container, causing object_get_canonical_path() to assert. Fix this by storing the canonical path during realize() so the information will still be available for device_unparent() in such cases. Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com> --- hw/core/qdev.c | 15 ++++++++++++--- include/hw/qdev-core.h | 1 + 2 files changed, 13 insertions(+), 3 deletions(-)