diff options
| author | Maxim Levitsky <mlevitsk@redhat.com> | 2020-10-06 14:38:58 +0200 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2020-10-12 11:50:50 -0400 |
| commit | 7bed89958bfbf40df9ca681cefbdca63abdde39d (patch) | |
| tree | 93edb2b6954d1a46a0f515115d28fb8e99461223 /softmmu/qdev-monitor.c | |
| parent | 7a8202c521a5d1ac9e289d5c2b5125a9310af178 (diff) | |
device_core: use drain_call_rcu in in qmp_device_add
Soon, a device removal might only happen on RCU callback execution.
This is okay for device-del which provides a DEVICE_DELETED event,
but not for the failure case of device-add. To avoid changing
monitor semantics, just drain all pending RCU callbacks on error.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Suggested-by: Stefan Hajnoczi <stefanha@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20200913160259.32145-4-mlevitsk@redhat.com>
[Don't use it in qmp_device_del. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'softmmu/qdev-monitor.c')
| -rw-r--r-- | softmmu/qdev-monitor.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/softmmu/qdev-monitor.c b/softmmu/qdev-monitor.c index e9b7228480..bcfb90a08f 100644 --- a/softmmu/qdev-monitor.c +++ b/softmmu/qdev-monitor.c @@ -803,6 +803,18 @@ void qmp_device_add(QDict *qdict, QObject **ret_data, Error **errp) return; } dev = qdev_device_add(opts, errp); + + /* + * Drain all pending RCU callbacks. This is done because + * some bus related operations can delay a device removal + * (in this case this can happen if device is added and then + * removed due to a configuration error) + * to a RCU callback, but user might expect that this interface + * will finish its job completely once qmp command returns result + * to the user + */ + drain_call_rcu(); + if (!dev) { qemu_opts_del(opts); return; |