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

["Michael S. Tsirkin" <mst@redhat.com>]

On Fri, Oct 16, 2015 at 01:07:28PM +0200, Christian Borntraeger wrote:
> 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

What fails, exactly?