Re: [virtio-comment] Block Device: Legacy SCSI 'cmd' Framing Requirements

On 24/02/19 13:30, Savir, Gil wrote:
> Regarding  Version 1.1 draft 01
> 
>  
> 
> When using Block-device, legacy scsi commands, while VIRTIO_F_ANY_LAYOUT
> is negotiated, it is not clear if ‘cmd’ field must reside in a single,
> separate device-readable buffer.
> 
> In Section 5.2.6.3 it is written, in general (without reference to
> VIRTIO_F_ANY_LAYOUT) that ‘cmd’ field must reside in a single buffer.
> 
> Section 5.2.6.4, 2^nd bullet describes framing requirements for SCSI
> commands, but does not refer to ‘cmd’ field.
> 
> I suggest adding description of ‘cmd’ field  framing requirement in this
> bullet, as well.

Indeed, the legacy SCSI interface's framing requirements override
VIRTIO_F_ANY_LAYOUT (and the impossibility of adjusting this was one of
the reasons to dro it).

Paolo