[Libguestfs] [COMMON PATCH v2 1/4] inject_virtio_win: match only vendor/device

[Laszlo Ersek]

On 3/7/23 20:40, Andrey Drobyshev wrote:
> From: Roman Kagan <rkagan at virtuozzo.com>
> 
> Since different hypervisor vendors are allowed to use their own vendor-id
> as PCI subsystem-vendor-id for virtio devices, during v2v conversion it
> makes sense to only match the vendor/device and not the full device "path"
> in the Windows registry.  This way the code will remain universal but will
> work for different hypervisor vendors.
> 
> Signed-off-by: Andrey Drobyshev <andrey.drobyshev at virtuozzo.com>
> Originally-by: Roman Kagan <rkagan at virtuozzo.com>
> ---
>  mlcustomize/inject_virtio_win.ml | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/mlcustomize/inject_virtio_win.ml b/mlcustomize/inject_virtio_win.ml
> index 4e977b3..8d72c5d 100644
> --- a/mlcustomize/inject_virtio_win.ml
> +++ b/mlcustomize/inject_virtio_win.ml
> @@ -110,10 +110,10 @@ and get_inspection g root =
>      virtio_win = ""; was_set = false }
>  
>  let scsi_class_guid = "{4D36E97B-E325-11CE-BFC1-08002BE10318}"
> -let viostor_legacy_pciid = "VEN_1AF4&DEV_1001&SUBSYS_00021AF4&REV_00"
> -let viostor_modern_pciid = "VEN_1AF4&DEV_1042&SUBSYS_11001AF4&REV_01"
> -let vioscsi_legacy_pciid = "VEN_1AF4&DEV_1004&SUBSYS_00081AF4&REV_00"
> -let vioscsi_modern_pciid = "VEN_1AF4&DEV_1048&SUBSYS_11001AF4&REV_01"
> +let viostor_legacy_pciid = "VEN_1AF4&DEV_1001"
> +let viostor_modern_pciid = "VEN_1AF4&DEV_1042"
> +let vioscsi_legacy_pciid = "VEN_1AF4&DEV_1004"
> +let vioscsi_modern_pciid = "VEN_1AF4&DEV_1048"
>  
>  let rec inject_virtio_win_drivers ({ g } as t) reg =
>    (* Copy the virtio drivers to the guest. *)

I wonder whether dropping the revision ID as well is a good idea. In the
virtio-1.0 spec, we have under 4.1.2.1 Device Requirements: PCI Device
Discovery:

    The PCI Subsystem Vendor ID and the PCI Subsystem Device ID MAY
    reflect the PCI Vendor and Device ID of the environment (for
    informational purposes by the driver).

    Non-transitional devices SHOULD have a PCI Device ID in the range
    0x1040 to 0x107f. Non-transitional devices SHOULD have a PCI
    Revision ID of 1 or higher. Non-transitional devices SHOULD have a
    PCI Subsystem Device ID of 0x40 or higher.

And in virtio-0.9.5, we have under 2.1 PCI Discovery:

    [...] The device must also have a Revision ID of 0 to
    match this speci
cation. [...]

So I think relaxing the PCI Revision ID is not necessary. But, it
shouldn't cause problems in practice either, I think. It won't allow for
cross-binding (the PCI Device IDs remain distinct).

Acked-by: Laszlo Ersek <lersek at redhat.com>