[PATCH 2/5] node_device: detect CSS devices

[Boris Fiuczynski]

On 9/14/20 7:41 AM, Erik Skultety wrote:
> On Fri, Sep 11, 2020 at 06:11:49PM +0200, Boris Fiuczynski wrote:
>> On 9/9/20 9:03 AM, Cornelia Huck wrote:
>>>>> [snip]
>>>>>>
>>>>>> +static int
>>>>>> +udevProcessCSS(struct udev_device *device,
>>>>>> +               virNodeDeviceDefPtr def)
>>>>>> +{
>>>>>> +    /* do not process EADM and CHSC devices to keep the list sane */
>>>>>> +    if (STREQ(def->driver, "eadm_subchannel") ||
>>>>>> +        STREQ(def->driver, "chsc_subchannel"))
>>>>> [2] Also mentions message subchannel, although apparently there are no Linux
>>>>> kernel drivers for that yet, IIUC that one would have to be added here as well
>>>>> as some point, is that correct?
>>>> We have never seen those, but we would want to add them here if they
>>>> have no relevance for the user.
>>> I think you want to filter message subchannels as well, my assumption
>>> is that libvirt will only care about I/O subchannels.
>>>
>> In
>> https://www.kernel.org/doc/html/latest/driver-api/s390-drivers.html
>> it is stated that for
>> Message subchannels. No Linux driver currently exists.
>>
>> Therefore I do not know how I could currently filter message subchannels
>> out. Due you want me to reverse the logic and just filter out everything but
>> "io_subchannel" instead (which I would regard as fencing the unknown)?
> 
> Well, I don't see a problem filtering out everything but the single thing you
> actually care about, rather than enumerating the things you don't care about
> and won't care about in the future, so yeah, I'd go with that.
> 
> Erik
> 
OK, I will do that.

-- 
Mit freundlichen Grüßen/Kind regards
    Boris Fiuczynski

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