24.09.2021 12:04, Kevin Wolf wrote:
object_property_add_child() fails (with &error_abort) if an
object with
the same name already exists. As long as QemuOpts is in use for -device
and device_add, it catches duplicate IDs before qdev_set_id() is even
called. However, for enabling non-QemuOpts code paths, we need to make
sure that the condition doesn't cause a crash, but fails gracefully.
Signed-off-by: Kevin Wolf <kwolf(a)redhat.com>
---
include/monitor/qdev.h | 2 +-
hw/xen/xen-legacy-backend.c | 3 ++-
softmmu/qdev-monitor.c | 16 ++++++++++------
3 files changed, 13 insertions(+), 8 deletions(-)
diff --git a/include/monitor/qdev.h b/include/monitor/qdev.h
index 389287eb44..7961308c75 100644
--- a/include/monitor/qdev.h
+++ b/include/monitor/qdev.h
@@ -9,6 +9,6 @@ void qmp_device_add(QDict *qdict, QObject **ret_data, Error **errp);
int qdev_device_help(QemuOpts *opts);
DeviceState *qdev_device_add(QemuOpts *opts, Error **errp);
-void qdev_set_id(DeviceState *dev, char *id);
+void qdev_set_id(DeviceState *dev, char *id, Error **errp);
#endif
diff --git a/hw/xen/xen-legacy-backend.c b/hw/xen/xen-legacy-backend.c
index dd8ae1452d..17aca85ddc 100644
--- a/hw/xen/xen-legacy-backend.c
+++ b/hw/xen/xen-legacy-backend.c
@@ -276,7 +276,8 @@ static struct XenLegacyDevice *xen_be_get_xendev(const char *type,
int dom,
xendev = g_malloc0(ops->size);
object_initialize(&xendev->qdev, ops->size, TYPE_XENBACKEND);
OBJECT(xendev)->free = g_free;
- qdev_set_id(DEVICE(xendev), g_strdup_printf("xen-%s-%d", type, dev));
+ qdev_set_id(DEVICE(xendev), g_strdup_printf("xen-%s-%d", type, dev),
+ &error_abort);
qdev_realize(DEVICE(xendev), xen_sysbus, &error_fatal);
object_unref(OBJECT(xendev));
diff --git a/softmmu/qdev-monitor.c b/softmmu/qdev-monitor.c
index 1207e57a46..c2af906df0 100644
--- a/softmmu/qdev-monitor.c
+++ b/softmmu/qdev-monitor.c
@@ -593,26 +593,27 @@ static BusState *qbus_find(const char *path, Error **errp)
}
/* Takes ownership of @id, will be freed when deleting the device */
-void qdev_set_id(DeviceState *dev, char *id)
+void qdev_set_id(DeviceState *dev, char *id, Error **errp)
According to recommendations in error.h, worth adding also return value (for example
true=success false=failure), so [..]
{
if (id) {
dev->id = id;
}
Unrelated but.. What's the strange logic?
Is it intended that with passed id=NULL we don't update dev->id variable but try to
do following logic with old dev->id?
if (dev->id) {
- object_property_add_child(qdev_get_peripheral(), dev->id,
- OBJECT(dev));
+ object_property_try_add_child(qdev_get_peripheral(), dev->id,
+ OBJECT(dev), errp);
} else {
static int anon_count;
gchar *name = g_strdup_printf("device[%d]", anon_count++);
- object_property_add_child(qdev_get_peripheral_anon(), name,
- OBJECT(dev));
+ object_property_try_add_child(qdev_get_peripheral_anon(), name,
+ OBJECT(dev), errp);
g_free(name);
}
}
DeviceState *qdev_device_add(QemuOpts *opts, Error **errp)
{
+ ERRP_GUARD();
DeviceClass *dc;
const char *driver, *path;
DeviceState *dev = NULL;
@@ -691,7 +692,10 @@ DeviceState *qdev_device_add(QemuOpts *opts, Error **errp)
}
}
- qdev_set_id(dev, g_strdup(qemu_opts_id(opts)));
+ qdev_set_id(dev, g_strdup(qemu_opts_id(opts)), errp);
+ if (*errp) {
+ goto err_del_dev;
+ }
[..] here we'll have
if (!qdev_set_id(...)) {
goto err_del_dev;
}
and no need for ERRP_GUARD.
/* set properties */
if (qemu_opt_foreach(opts, set_property, dev, errp)) {
--
Best regards,
Vladimir