Currently objects specified on the command-line are only partially
cleaned up when 'object_del' is issued in either HMP or QMP: the
object itself is fully finalized, but the QemuOpts are not removed.
This results in the following behavior:
x86_64-softmmu/qemu-system-x86_64 -monitor stdio \
-object memory-backend-ram,id=ram1,size=256M
QEMU 2.7.91 monitor - type 'help' for more information
(qemu) object_del ram1
(qemu) object_del ram1
object 'ram1' not found
(qemu) object_add memory-backend-ram,id=ram1,size=256M
Duplicate ID 'ram1' for object
Try "help object_add" for more information
which can be an issue for use-cases like memory hotplug.
This happens on the HMP side because hmp_object_add() attempts to
create a temporary QemuOpts entry with ID 'ram1', which ends up
conflicting with the command-line-created entry, since it was never
cleaned up during the previous hmp_object_del() call.
We address this by adding checks in {qmp,hmp}_object_del to determine
whether an option group entry matching the object's ID is present,
and removing it if it is.
Note that qmp_object_add() never attempts to create a temporary
QemuOpts entry, so it does not encounter the duplicate ID error,
which is why this isn't generally visible in libvirt.
Cc: "Dr. David Alan Gilbert" <[email protected]>
Cc: Markus Armbruster <[email protected]>
Cc: Eric Blake <[email protected]>
Cc: Daniel Berrange <[email protected]>
Signed-off-by: Michael Roth <[email protected]>
---
hmp.c | 10 ++++++++++
qmp.c | 10 ++++++++++
2 files changed, 20 insertions(+)
diff --git a/hmp.c b/hmp.c
index b869617..99b8bf3 100644
--- a/hmp.c
+++ b/hmp.c
@@ -2072,6 +2072,16 @@ void hmp_object_del(Monitor *mon, const QDict *qdict)
user_creatable_del(id, &err);
hmp_handle_error(mon, &err);
+
+ /* if object was defined on the command-line, remove its corresponding
+ * option group entry
+ */
+ if (err == NULL) {
+ QemuOptsList *opt_group = qemu_find_opts_err("object", &err);
+ if (opt_group) {
+ qemu_opts_del(qemu_opts_find(opt_group, id));
+ }
+ }
}
void hmp_info_memdev(Monitor *mon, const QDict *qdict)
diff --git a/qmp.c b/qmp.c
index 0028f0b..87c545d 100644
--- a/qmp.c
+++ b/qmp.c
@@ -686,6 +686,16 @@ void qmp_object_add(const char *type, const char *id,
void qmp_object_del(const char *id, Error **errp)
{
user_creatable_del(id, errp);
+
+ /* if object was defined on the command-line, remove its corresponding
+ * option group entry
+ */
+ if (!(errp && *errp)) {
+ QemuOptsList *opt_group = qemu_find_opts_err("object", errp);
+ if (opt_group) {
+ qemu_opts_del(qemu_opts_find(opt_group, id));
+ }
+ }
}
MemoryDeviceInfoList *qmp_query_memory_devices(Error **errp)
--
1.9.1
