From 48aa83a2a3e42665e3e3e390909ebc147e234f73 Mon Sep 17 00:00:00 2001
From: Markus Armbruster <armbru@redhat.com>
Date: Fri, 17 Jan 2014 17:07:57 +0100
Subject: [PATCH 07/11] qdev: Do not let the user try to device_add when it cannot work
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RH-Author: Markus Armbruster <armbru@redhat.com>
Message-id: <1389978479-30595-8-git-send-email-armbru@redhat.com>
Patchwork-id: 56788
O-Subject: [PATCH 7.0 qemu-kvm 7/9] qdev: Do not let the user try to device_add when it cannot work
Bugzilla: 669524
RH-Acked-by: Eduardo Habkost <ehabkost@redhat.com>
RH-Acked-by: Michael S. Tsirkin <mst@redhat.com>
RH-Acked-by: Marcel Apfelbaum <marcel.a@redhat.com>

Such devices have always been unavailable and omitted from the list of
available devices shown by device_add help.  Until commit 18b6dad
silently broke the former, setting up nasty traps for unwary users,
like this one:

    $ qemu-system-x86_64 -nodefaults -monitor stdio -display none
    QEMU 1.6.50 monitor - type 'help' for more information
    (qemu) device_add apic
    Segmentation fault (core dumped)

I call that a regression.  Fix it.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel.a@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
(cherry picked from commit 7ea5e78f3d8d64e99c4017ea211b7518f2629756)
---
 qdev-monitor.c | 5 +++++
 1 file changed, 5 insertions(+)

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
 qdev-monitor.c |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/qdev-monitor.c b/qdev-monitor.c
index eb05b4c..da7fe0d 100644
--- a/qdev-monitor.c
+++ b/qdev-monitor.c
@@ -490,6 +490,11 @@ DeviceState *qdev_device_add(QemuOpts *opts)
     }
 
     dc = DEVICE_CLASS(oc);
+    if (dc->cannot_instantiate_with_device_add_yet) {
+        qerror_report(QERR_INVALID_PARAMETER_VALUE, "driver",
+                      "pluggable device type");
+        return NULL;
+    }
 
     /* find bus */
     path = qemu_opt_get(opts, "bus");
-- 
1.7.1