Re: [Qemu-devel] device_add error handling regressed in v1.5.0

[Markus Armbruster <armbru@redhat.com>]

Markus Armbruster <armbru@redhat.com> writes:

> Paolo Bonzini <pbonzini@redhat.com> writes:
>
>> Il 17/01/2014 11:23, Markus Armbruster ha scritto:
>>> Watch this:
>>>
>>>     $ upstream-qemu -nodefaults -S -display none -monitor stdio
>>>     QEMU 1.7.50 monitor - type 'help' for more information
>>>     (qemu) device_add e1000,netdev=xxx
>>>     Property 'e1000.netdev' can't find value 'xxx'
>>>     (qemu) info qtree
> [...]
>>>     Segmentation fault (core dumped)
>>>
>>> Even though device_add failed, it still created a node in the qtree!
>>>
>>> Same issue observed with scsi-hd.  Looks like a qdev problem, not a
>>> device problem.
>>>
>>> git-bisect blames this one:
>>>
>>> e0a83fc2c1582dc8d4453849852ebe6c258b7c3a is the first bad commit
>>> commit e0a83fc2c1582dc8d4453849852ebe6c258b7c3a
>>> Author: Paolo Bonzini <pbonzini@redhat.com>
>>> Date:   Tue Apr 2 15:50:00 2013 +0200
>>>
>>>     qom: do nothing on unparent of object without parent
>>>
>>>     Otherwise, device_unparent will fail to get a canonical path of
>>>     the object.
>>>
>>>     Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
>>>     Message-id: 1364910600-3418-1-git-send-email-pbonzini@redhat.com
>>>     Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
>>>
>>
>> I think Amos had a fix for this.
>
> Amos, do you?

Found it: "[PATCH v2] qdev: add the device to the QOM tree before using
it to set a link" seems to fix it.