On 01/28/2015 03:07 PM, Clemens Ladisch wrote:
> The driver was using the vendor ID 0xd00d1e from the FireWire core.
> However, this ID was not registered, and invalid.
>
> Instead, use the vendor/version IDs that now are officially assigned to
> firewire-serial:
> https://ieee1394.wiki.kernel.org/index.php/IEEE_OUI_Assignments
That's great that we have official OUIs now, but I have to NACK this
patch as is.
The problem is a host with the old OUIs will not recognize a remote
unit with the new OUIs, and vice versa.
Even though the new ids could be added to the unit driver's id_table,
(which would let hosts with the new OUI connect to either OUI remote),
it wouldn't let 3.19- hosts connect to 3.20+ hosts.
Regards,
Peter Hurley
On Feb 02 Peter Hurley wrote:
> On 01/28/2015 03:07 PM, Clemens Ladisch wrote:
> > The driver was using the vendor ID 0xd00d1e from the FireWire core.
> > However, this ID was not registered, and invalid.
> >
> > Instead, use the vendor/version IDs that now are officially assigned to
> > firewire-serial:
> > https://ieee1394.wiki.kernel.org/index.php/IEEE_OUI_Assignments
>
> That's great that we have official OUIs now, but I have to NACK this
> patch as is.
>
> The problem is a host with the old OUIs will not recognize a remote
> unit with the new OUIs, and vice versa.
>
> Even though the new ids could be added to the unit driver's id_table,
> (which would let hosts with the new OUI connect to either OUI remote),
> it wouldn't let 3.19- hosts connect to 3.20+ hosts.
Actually there are no 3.19- hosts that speak fwserial; there are only
staging hosts that do so. So, with this patch added, certain staging
hosts would become unable to talk with certain other staging hosts (and
with future Linux hosts, once fwserial gets merged upstream).
Both fwserial-the-implementation and fwserial-the-protocol are your own,
and as yet unmerged. (In addition, there does not yet exist a second
implementation, AFAIK.) So I'd say there is still opportunity to improve
the protocol even in incompatible ways if justified. Switching to
valid identifiers may very well be such a justifiable change.
--
Stefan Richter
-=====-===== --=- ---==
http://arcgraph.de/sr/
On 02/03/2015 03:44 AM, Stefan Richter wrote:
> On Feb 02 Peter Hurley wrote:
>> On 01/28/2015 03:07 PM, Clemens Ladisch wrote:
>>> The driver was using the vendor ID 0xd00d1e from the FireWire core.
>>> However, this ID was not registered, and invalid.
>>>
>>> Instead, use the vendor/version IDs that now are officially assigned to
>>> firewire-serial:
>>> https://ieee1394.wiki.kernel.org/index.php/IEEE_OUI_Assignments
>>
>> That's great that we have official OUIs now, but I have to NACK this
>> patch as is.
>>
>> The problem is a host with the old OUIs will not recognize a remote
>> unit with the new OUIs, and vice versa.
>>
>> Even though the new ids could be added to the unit driver's id_table,
>> (which would let hosts with the new OUI connect to either OUI remote),
>> it wouldn't let 3.19- hosts connect to 3.20+ hosts.
>
> Actually there are no 3.19- hosts that speak fwserial; there are only
> staging hosts that do so. So, with this patch added, certain staging
> hosts would become unable to talk with certain other staging hosts (and
> with future Linux hosts, once fwserial gets merged upstream).
The breakage seems gratuitous especially considering the existing OUI
has been in use for a decade.
> Both fwserial-the-implementation and fwserial-the-protocol are your own,
> and as yet unmerged.
I've been waiting for you to work through the patch backlog from Feb and
Mar of last year before sending you more patches to merge fwserial.
> (In addition, there does not yet exist a second
> implementation, AFAIK.) So I'd say there is still opportunity to improve
> the protocol even in incompatible ways if justified. Switching to
> valid identifiers may very well be such a justifiable change.
I would appreciate you sharing any suggestions for improving the protocol.
While I concede the protocol is not perfect, I'm struggling to see how
changing the OUI improves it.
Regards,
Peter Hurley
On Feb 03 Peter Hurley wrote:
> On 02/03/2015 03:44 AM, Stefan Richter wrote:
> > On Feb 02 Peter Hurley wrote:
[...]
> >> The problem is a host with the old OUIs will not recognize a remote
> >> unit with the new OUIs, and vice versa.
> >>
> >> Even though the new ids could be added to the unit driver's id_table,
> >> (which would let hosts with the new OUI connect to either OUI remote),
> >> it wouldn't let 3.19- hosts connect to 3.20+ hosts.
> >
> > Actually there are no 3.19- hosts that speak fwserial; there are only
> > staging hosts that do so. So, with this patch added, certain staging
> > hosts would become unable to talk with certain other staging hosts (and
> > with future Linux hosts, once fwserial gets merged upstream).
>
> The breakage seems gratuitous especially considering the existing OUI
> has been in use for a decade.
This ID has never been in use to identify the specifier of a unit
architecture though, nor has it been used otherwise in any protocol.
And the way how the ID /was/ used doesn't make it an OUI.
[Since 7.5 years ago the new firewire-core puts a fixed, unregistered
value into the config ROM's root dir's vendor ID leaf, whereas until
4 years ago ieee1394 has been copying the upper 24 bits of the node's
EUI-64 there. Years counted according to mainline Linux releases.
As another historical note, 7.5 years ago the occupied OUI space consisted
of 10456 IDs from 0…acde48, now it is 19896 IDs from 0…fcffaa.]
> > Both fwserial-the-implementation and fwserial-the-protocol are your own,
> > and as yet unmerged.
>
> I've been waiting for you to work through the patch backlog from Feb and
> Mar of last year before sending you more patches to merge fwserial.
If there is one or another patch among them which directly blocks your
work on fwserial, ping me so that I can reconsider priorities. Though if
you were just expressing dissatisfaction with the subsystem's maintenance
progress, well, then that's noted and quite agreed.
> > (In addition, there does not yet exist a second
> > implementation, AFAIK.) So I'd say there is still opportunity to improve
> > the protocol even in incompatible ways if justified. Switching to
> > valid identifiers may very well be such a justifiable change.
>
> I would appreciate you sharing any suggestions for improving the protocol.
>
> While I concede the protocol is not perfect, I'm struggling to see how
> changing the OUI improves it.
The difference of course is nothing more than that the interoperability of
the specifier_ID:software_version tuple either depends on made-up IDs, or
on IDs whose uniqueness is based on a proper chain of registrations.
--
Stefan Richter
-=====-===== --=- ---==
http://arcgraph.de/sr/