hw/nvram: Always register FW_CFG_DATA_GENERATOR_INTERFACE

While the FW_CFG_DATA_GENERATOR_INTERFACE is only consumed
by a device only available using system-mode (fw_cfg), it is
implemented by a crypto component (tls-cipher-suites) which
is always available when crypto is used.

Commit 69699f3055 introduced the following error in the
qemu-storage-daemon binary:

  $ echo -e \
    '{"execute": "qmp_capabilities"}\r\n{"execute": "qom-list-types"}\r\n{"execute": "quit"}\r\n' \
    | storage-daemon/qemu-storage-daemon --chardev stdio,id=qmp0  --monitor qmp0
  {"QMP": {"version": {"qemu": {"micro": 50, "minor": 1, "major": 5}, "package": ""}, "capabilities": ["oob"]}}
  {"return": {}}
  missing interface 'fw_cfg-data-generator' for object 'tls-creds'
  Aborted (core dumped)

Since QOM dependencies are resolved at runtime, this issue
could not be triggered at linktime, and we don't have test
running the qemu-storage-daemon binary.

Fix by always registering the QOM interface.

Reported-by: Kevin Wolf <kwolf@redhat.com>
Fixes: 69699f3055 ("crypto/tls-cipher-suites: Produce fw_cfg consumable blob")
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201006111909.2302081-2-philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 0 insertions, 7 deletions

diff --git a/hw/nvram/fw_cfg.c b/hw/nvram/fw_cfg.c
index 0e95d057fd..08539a1aab 100644
--- a/hw/nvram/fw_cfg.c
+++ b/hw/nvram/fw_cfg.c
@@ -1360,18 +1360,11 @@ static const TypeInfo fw_cfg_mem_info = {
     .class_init    = fw_cfg_mem_class_init,
 };
 
-static const TypeInfo fw_cfg_data_generator_interface_info = {
-    .parent = TYPE_INTERFACE,
-    .name = TYPE_FW_CFG_DATA_GENERATOR_INTERFACE,
-    .class_size = sizeof(FWCfgDataGeneratorClass),
-};
-
 static void fw_cfg_register_types(void)
 {
     type_register_static(&fw_cfg_info);
     type_register_static(&fw_cfg_io_info);
     type_register_static(&fw_cfg_mem_info);
-    type_register_static(&fw_cfg_data_generator_interface_info);
 }
 
 type_init(fw_cfg_register_types)