Re: [Qemu-devel] [PULL 25/26] block: Remove deprecated -drive option serial

[Thomas Huth <thuth@redhat.com>]

On 22.06.2018 16:25, Kevin Wolf wrote:
> Am 22.06.2018 um 15:36 hat Christian Borntraeger geschrieben:
>>
>>
>> On 06/22/2018 02:55 PM, Kevin Wolf wrote:
>>> Am 22.06.2018 um 13:38 hat Christian Borntraeger geschrieben:
>>>>
>>>> On 06/15/2018 04:21 PM, Kevin Wolf wrote:
>>>>> The -drive option serial was deprecated in QEMU 2.10. It's time to
>>>>> remove it.
>>>>>
>>>>> Tests need to be updated to set the serial number with -global instead
>>>>> of using the -drive option.
>>>>
>>>> libvirt 4.5 still creates those (at least on s390x)
>>>>
>>>>     <disk type='file' device='disk'>
>>>>       <driver name='qemu' type='qcow2' cache='none' io='native' iothread='1'/>
>>>>       <source file='/var/lib/libvirt/qemu/image.zhyp137'/>
>>>>       <target dev='hda' bus='virtio'/>
>>>>       <serial>skel</serial>
>>>>       <boot order='1'/>
>>>>       <address type='ccw' cssid='0xfe' ssid='0x0' devno='0x0000'/>
>>>>     </disk>
>>>>
>>>>
>>>> -> 
>>>> [...]
>>>> -drive file=/var/lib/libvirt/qemu/image.zhyp137,format=qcow2,if=none,id=drive-virtio-disk0,serial=skel,cache=none,aio=native -device virtio-blk-ccw,iothread=iothread1,scsi=off,devno=fe.0.0000,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1,write-cache=on 
>>>> [...]
>>>>
>>>> 2018-06-22T11:25:20.946024Z qemu-system-s390x: -drive file=/var/lib/libvirt/qemu/image.zhyp137,format=qcow2,if=none,id=drive-virtio-disk0,serial=skel,cache=none,aio=native: Block format 'qcow2' does not support the option 'serial'
>>>> 2018-06-22 11:25:21.098+0000: shutting down, reason=failed
>>>>
>>>> So it seems that this breaks s390x.
>>
>> To me it seems that this is also broken on x86.
>>>
>>> Thanks for bringing this up. libvirt should fix this before QEMU 3.0 is
>>> released.
>>
>> I think this is definitely too short notice. We should not break existing
>> setups just by insisting that users have to update libvirt when they update
>> QEMU. Yes, this might be our policy, but doing so "just because we can"
>> is certainly a very bad attitude. I see no fundamental technical reason why
>> we should not revert this change.
> 
> This was in fact one release longer than our deprecation policy says.

Actually, if we assume that the chapter in qemu-doc.texi is the
"official" way to deprecate things, these options are only officially
deprecated since QEMU v2.12, since we missed to add them to the
deprecation chapter earlier:

https://git.qemu.org/?p=qemu.git;a=commitdiff;h=c08d46a9

(We've mentioned them in
https://wiki.qemu.org/ChangeLog/2.10#Deprecated_options already, though)

 Thomas