Re: [Qemu-devel] [PATCH v2 3/3] virtio-blk: switch off scsi-passthrough by default

[Christian Borntraeger <borntraeger@de.ibm.com>]

Am 16.10.2015 um 12:44 schrieb Cornelia Huck:
> On Fri, 16 Oct 2015 12:32:52 +0200
> Christian Borntraeger <borntraeger@de.ibm.com> wrote:
> 
>> Am 16.10.2015 um 12:25 schrieb Cornelia Huck:
>>> Devices that are compliant with virtio-1 do not support scsi
>>> passthrough any more (and it has not been a recommended setup
>>> anyway for quite some time). To avoid having to switch it off
>>> explicitly in newer qemus that turn on virtio-1 by default, let's
>>> switch the default to scsi=false for 2.5.
>>>
>>> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
>>> ---
>>>  hw/block/virtio-blk.c | 2 +-
>>>  include/hw/compat.h   | 6 +++++-
>>>  2 files changed, 6 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c
>>> index 8beb26b..999dbd7 100644
>>> --- a/hw/block/virtio-blk.c
>>> +++ b/hw/block/virtio-blk.c
>>> @@ -975,7 +975,7 @@ static Property virtio_blk_properties[] = {
>>>      DEFINE_PROP_STRING("serial", VirtIOBlock, conf.serial),
>>>      DEFINE_PROP_BIT("config-wce", VirtIOBlock, conf.config_wce, 0, true),
>>>  #ifdef __linux__
>>> -    DEFINE_PROP_BIT("scsi", VirtIOBlock, conf.scsi, 0, true),
>>> +    DEFINE_PROP_BIT("scsi", VirtIOBlock, conf.scsi, 0, false),
>>>  #endif
>>>      DEFINE_PROP_BIT("request-merging", VirtIOBlock, conf.request_merging, 0,
>>>                      true),
>>> diff --git a/include/hw/compat.h b/include/hw/compat.h
>>> index 095de5d..93e71af 100644
>>> --- a/include/hw/compat.h
>>> +++ b/include/hw/compat.h
>>> @@ -2,7 +2,11 @@
>>>  #define HW_COMPAT_H
>>>
>>>  #define HW_COMPAT_2_4 \
>>> -        /* empty */
>>> +        {\
>>> +            .driver   = "virtio-blk-device",\
>>> +            .property = "scsi",\
>>> +            .value    = "true",\
>>
>> does that work?
> 
> It did for me :)
> 
>>
>> If yes, would it make sense to convert the things in HW_COMPAT_2_3 from
>> pci to device, e.g.
>>
>>
>>         {\
>> -           .driver   = "virtio-blk-pci",\
>> +           .driver   = "virtio-blk-device",\
>>             .property = "any_layout",\
>>             .value    = "off",\
>> ...
> 
> Not sure: We don't have 2.3 compat for ccw... but would give a better
> template for later changes.

Yes. But this can be an addon patch. 

Lets keep this patch as is to have scsi=off as default for virtio 1.0

(some iotests do fail because of this)

Christian