Linux Virtualization - Sep 2014 - [PATCH] virtio-pci: also bind to Amazon PCI vendor ID

From: Anthony Liguori <aliguori at amazon.com>

See https://issues.oasis-open.org/browse/VIRTIO-16 although it
was prematurely closed.

Red Hat has non-redistributable Windows drivers and Microsoft
will not allow anyone else to WHQL certify drivers using that
vendor ID.  That makes it impossible to use virtio drivers with
a Windows guest without changing the vendor ID.

Cc: Matt Wilson <msw at amazon.com>
Cc: Rusty Russell <rusty at rustcorp.com.au>
Cc: Michael Tsirkin <mst at redhat.com>
Signed-off-by: Anthony Liguori <aliguori at amazon.com>
---
 drivers/virtio/virtio_pci.c |    2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
index 101db3f..9cbac33 100644
--- a/drivers/virtio/virtio_pci.c
+++ b/drivers/virtio/virtio_pci.c
@@ -93,6 +93,8 @@ struct virtio_pci_vq_info
 /* Qumranet donated their vendor ID for devices 0x1000 thru 0x10FF. */
 static DEFINE_PCI_DEVICE_TABLE(virtio_pci_id_table) = {
 	{ PCI_DEVICE(0x1af4, PCI_ANY_ID) },
+	/* Amazon.com vendor ID */
+	{ PCI_DEVICE(0x1d0f, PCI_ANY_ID) },
 	{ 0 }
 };
 
-- 
1.7.9.5

On Sun, Sep 14, 2014 at 08:29:33PM -0700, Anthony Liguori
wrote:
> From: Anthony Liguori <aliguori at amazon.com>
> 
> See https://issues.oasis-open.org/browse/VIRTIO-16 although it
> was prematurely closed.
> 
> Red Hat has non-redistributable Windows drivers and Microsoft
> will not allow anyone else to WHQL certify drivers using that
> vendor ID.  That makes it impossible to use virtio drivers with
> a Windows guest without changing the vendor ID.
> 
> Cc: Matt Wilson <msw at amazon.com>
> Cc: Rusty Russell <rusty at rustcorp.com.au>
> Cc: Michael Tsirkin <mst at redhat.com>
> Signed-off-by: Anthony Liguori <aliguori at amazon.com>
Reviewed-by: Matt Wilson <msw at amazon.com>

--msw
> ---
>  drivers/virtio/virtio_pci.c |    2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
> index 101db3f..9cbac33 100644
> --- a/drivers/virtio/virtio_pci.c
> +++ b/drivers/virtio/virtio_pci.c
> @@ -93,6 +93,8 @@ struct virtio_pci_vq_info
>  /* Qumranet donated their vendor ID for devices 0x1000 thru 0x10FF. */
>  static DEFINE_PCI_DEVICE_TABLE(virtio_pci_id_table) = {
>  	{ PCI_DEVICE(0x1af4, PCI_ANY_ID) },
> +	/* Amazon.com vendor ID */
> +	{ PCI_DEVICE(0x1d0f, PCI_ANY_ID) },
>  	{ 0 }
>  };
>

On Sun, Sep 14, 2014 at 08:29:33PM -0700, Anthony Liguori
wrote:
> From: Anthony Liguori <aliguori at amazon.com>
> 
> See https://issues.oasis-open.org/browse/VIRTIO-16 although it
> was prematurely closed.
The reason it was closed is described in the comments. and I quote:
" I think anyone can use a different subsystem vendor id and whql the
driver. virtio-102 will make this even easier, by making the subsystem
id flexible. Let's close this and re-open if someone tries to do this
and runs into a problem. "

Look here for example:
https://github.com/YanVugenfirer/kvm-guest-drivers-windows/blob/master/NetKVM/NDIS5/wxp/netkvm.inf
Replace SUBSYS_00011AF4 with SUBSYS_00011D0F, and you will get
a virtio-net driver that (I think) you should be able to WHQL.

On the host side, you will need a QEMU patch to allow libvirt control of
the subsystem vendor ID.

All this while all Linux guests will keep working without changes,
which seems like a better approach.

Looking on the web, I found:
http://download.microsoft.com/download/1/6/1/161ba512-40e2-4cc9-843a-923143f3456c/pciidspec-11.doc
"Test will read and properly concatenate PCI IDs and verify
uniqueness"
this is likely what you are running into: IDs must be unique,
so if you want to put your driver in Microsoft's database,
it must match a different set of IDs.
But you should not need to change the vendor ID to make them unique,
changing subsystem vendor ID will do.

Did you try this?

> Red Hat has non-redistributable Windows drivers and Microsoft
> will not allow anyone else to WHQL certify drivers using that
> vendor ID. 
Don't see what Red Hat's windows drivers have to do with Linux really.
Amazon.com can do whatever it wants with its vendor ID, and if there is a 
hypervisor with a different vendor ID that can use the virtio drivers, this
patch is required.
The following would be a reasonable commit log in that case:

"Amazon.com uses PV devices with vendor ID 0x1d0f that are otherwise
 compatible with Linux virtio drivers. Add 0x1d0f ID to the list
 to make Linux work with these devices."
Feel free to use :)


But I'd like to note that by doing this on the hypervisor side,
you lose the ability to run older Linux guests,
and create work for all distros who now need to update their
kernels to work with your ID, apparently for no good reason.

So if this isn't out in the field yet, I would suggest examining
the alternative listed above.

OTOH if it *is* decided this is going to be out there in the field, please add
the new devices to the PCI IDs list.
http://pci-ids.ucw.cz/
Otherwise there's no way to be sure someone won't try to
use these IDs for something else.
> That makes it impossible to use virtio drivers with
> a Windows guest without changing the vendor ID.
Hardly impossible: virtio drivers are available from a
variety of sources.

But this is IMO beside the point.
> Cc: Matt Wilson <msw at amazon.com>
> Cc: Rusty Russell <rusty at rustcorp.com.au>
> Cc: Michael Tsirkin <mst at redhat.com>
> Signed-off-by: Anthony Liguori <aliguori at amazon.com>
I'd like to see the response/confirmation of the above, and/or the
commit log replaced before this patch is applied.

Thanks!
> ---
>  drivers/virtio/virtio_pci.c |    2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
> index 101db3f..9cbac33 100644
> --- a/drivers/virtio/virtio_pci.c
> +++ b/drivers/virtio/virtio_pci.c
> @@ -93,6 +93,8 @@ struct virtio_pci_vq_info
>  /* Qumranet donated their vendor ID for devices 0x1000 thru 0x10FF. */
>  static DEFINE_PCI_DEVICE_TABLE(virtio_pci_id_table) = {
>  	{ PCI_DEVICE(0x1af4, PCI_ANY_ID) },
> +	/* Amazon.com vendor ID */
> +	{ PCI_DEVICE(0x1d0f, PCI_ANY_ID) },
>  	{ 0 }
>  };
>  
> -- 
> 1.7.9.5

Hi Michael,

On Mon, Sep 15, 2014 at 1:20 AM, Michael S. Tsirkin <mst at redhat.com>
wrote:
> On Sun, Sep 14, 2014 at 08:29:33PM -0700, Anthony Liguori wrote:
>> From: Anthony Liguori <aliguori at amazon.com>
>>
>> See https://issues.oasis-open.org/browse/VIRTIO-16 although it
>> was prematurely closed.
>
> The reason it was closed is described in the comments. and I quote:
> " I think anyone can use a different subsystem vendor id and whql the
> driver. virtio-102 will make this even easier, by making the subsystem
> id flexible. Let's close this and re-open if someone tries to do this
> and runs into a problem. "
>
> Look here for example:
>
https://github.com/YanVugenfirer/kvm-guest-drivers-windows/blob/master/NetKVM/NDIS5/wxp/netkvm.inf
> Replace SUBSYS_00011AF4 with SUBSYS_00011D0F, and you will get
> a virtio-net driver that (I think) you should be able to WHQL.
The string you are referencing is the device description which is part
of what forms the device instance id.  You can read more at
http://msdn.microsoft.com/en-us/library/windows/hardware/ff541327%28v=vs.85%29.aspx.
Including a SUBSYS entry is mandatory in modern Windows drivers.

But this is independent of WHQL certification.  My understanding is
that Microsoft will only allow the owner of the PCI Vendor ID to WHQL
drivers.  As best as I know, this is not a publicly documented
process.

Do you have any examples of anyone else successfuling WHQL'ing drivers
by just changing the subsystem ID?  Microsoft has specific rules about
the usage of the subsystem ID.  See
http://msdn.microsoft.com/en-us/library/windows/hardware/dn653567%28v=vs.85%29.aspx.
I don't think it is intended to enable a totally different
implementation of the driver based on subsystem ID.

Certainly, this is not expected with typical PCI devices.
> On the host side, you will need a QEMU patch to allow libvirt control of
> the subsystem vendor ID.
>
> All this while all Linux guests will keep working without changes,
> which seems like a better approach.
>
> Looking on the web, I found:
>
http://download.microsoft.com/download/1/6/1/161ba512-40e2-4cc9-843a-923143f3456c/pciidspec-11.doc
> "Test will read and properly concatenate PCI IDs and verify
uniqueness"
> this is likely what you are running into: IDs must be unique,
> so if you want to put your driver in Microsoft's database,
> it must match a different set of IDs.
> But you should not need to change the vendor ID to make them unique,
> changing subsystem vendor ID will do.
>
> Did you try this?
You cannot submit a modified kvm-guest-drivers.git for WHQL
certification as the licensing is constructed in such a way as to
prevent that.
>> Red Hat has non-redistributable Windows drivers and Microsoft
>> will not allow anyone else to WHQL certify drivers using that
>> vendor ID.
>
> Don't see what Red Hat's windows drivers have to do with Linux
really.
> Amazon.com can do whatever it wants with its vendor ID, and if there is a
> hypervisor with a different vendor ID that can use the virtio drivers, this
> patch is required.
> The following would be a reasonable commit log in that case:
>
> "Amazon.com uses PV devices with vendor ID 0x1d0f that are otherwise
>  compatible with Linux virtio drivers. Add 0x1d0f ID to the list
>  to make Linux work with these devices."
> Feel free to use :)
>
>
> But I'd like to note that by doing this on the hypervisor side,
> you lose the ability to run older Linux guests,
> and create work for all distros who now need to update their
> kernels to work with your ID, apparently for no good reason.
>
> So if this isn't out in the field yet, I would suggest examining
> the alternative listed above.
I am very happy to use any alternative mechanism that allows for
virtio to be used with a wide variety of guests.  Many other companies
have also struggled with this and AFAIK no one has had much success.
> OTOH if it *is* decided this is going to be out there in the field, please
add
> the new devices to the PCI IDs list.
> http://pci-ids.ucw.cz/
> Otherwise there's no way to be sure someone won't try to
> use these IDs for something else.
PCI-SIG assigns vendor IDs and 0x1d0f is assigned to Amazon.  See
https://www.pcisig.com/membership/vid_search/

Vendors self-manage device IDs and we have allocated 0x1000-0x103f to
virtio devices.
>> That makes it impossible to use virtio drivers with
>> a Windows guest without changing the vendor ID.
>
> Hardly impossible: virtio drivers are available from a
> variety of sources.
Examples?

Regards,

Anthony Liguori
>
> But this is IMO beside the point.
>
>> Cc: Matt Wilson <msw at amazon.com>
>> Cc: Rusty Russell <rusty at rustcorp.com.au>
>> Cc: Michael Tsirkin <mst at redhat.com>
>> Signed-off-by: Anthony Liguori <aliguori at amazon.com>
>
> I'd like to see the response/confirmation of the above, and/or the
> commit log replaced before this patch is applied.
>
> Thanks!
>
>> ---
>>  drivers/virtio/virtio_pci.c |    2 ++
>>  1 file changed, 2 insertions(+)
>>
>> diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
>> index 101db3f..9cbac33 100644
>> --- a/drivers/virtio/virtio_pci.c
>> +++ b/drivers/virtio/virtio_pci.c
>> @@ -93,6 +93,8 @@ struct virtio_pci_vq_info
>>  /* Qumranet donated their vendor ID for devices 0x1000 thru 0x10FF. */
>>  static DEFINE_PCI_DEVICE_TABLE(virtio_pci_id_table) = {
>>       { PCI_DEVICE(0x1af4, PCI_ANY_ID) },
>> +     /* Amazon.com vendor ID */
>> +     { PCI_DEVICE(0x1d0f, PCI_ANY_ID) },
>>       { 0 }
>>  };
>>
>> --
>> 1.7.9.5