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To: Markus Armbruster , qemu-devel@nongnu.org References: <87tv0vzrwj.fsf@dusky.pond.sub.org> From: Paolo Bonzini Message-ID: <6fc8633a-6d91-b83a-e6cd-5f714ccaf9ea@redhat.com> Date: Mon, 4 May 2020 16:58:54 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.6.0 MIME-Version: 1.0 In-Reply-To: <87tv0vzrwj.fsf@dusky.pond.sub.org> Content-Language: en-US X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=205.139.110.120; envelope-from=pbonzini@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/05/04 04:24:57 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "Daniel P. Berrange" , Eduardo Habkost Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 04/05/20 16:38, Markus Armbruster wrote: > makes no progreess because OBJECT(dev)->parent is still null, and > therefore object_unparent() does nothing. > > Possible culprit: qdev_try_create() calls qdev_set_parent_bus(), which > adds the device to the bus, but leaves ->parent null. If this isn't > wrong outright, it's at least a dangerous state. > > Work-around: call qdev_set_id(dev, NULL) right after qdev_create(). > This sets ->parent. That's a good one, and especially a safe one, since it matches qdev_device_add. It has the disadvantage of having to touch all qdev_create() calls. Even better however would be to move the bus argument (and thus qdev_set_parent_bus) to qdev_init, and likewise in qdev_device_add move qdev_set_id after qemu_opt_foreach. I looked at the property setters and couldn't find anything suspicious (somewhat to my surprise), but I haven't honestly tried. Paolo