[ofw] RE: When one can release CA interface

[Smith, Stan]

Leonid Keller wrote:
> I don't quite understand that.
> If CA has been deregistered, i.e. ib_deregister_ca() has been called,
> there is more CI_CA object.
> All resources (PDs, CQs, QPs) are released.
> How can IBAL send to CA MADs ?

The CI_CA object still exists due to the reference still held on the HCA.

>
>
>> -----Original Message-----
>> From: Smith, Stan [mailto:stan.smith at intel.com]
>> Sent: Tuesday, September 01, 2009 7:29 PM
>> To: Leonid Keller; Tzachi Dar
>> Cc: ofw_list
>> Subject: RE: When one can release CA interface
>>
>> Leonid Keller wrote:
>>> fdo_release_resources() in bus_pnp.c releases the last interface
>>> with low-level driver only after IBAL cleanup with the following
>>> explanation:
>>>
>>> /* AL needs the HCA to stick around until AL cleanup has completed.
>>> ... */
>>>
>>> My question is - why ?
>>> How may/can IBAL proceed to work with HCA after CA has been
>>> deregistered ? What kind of works could be still pending ?
>>
>>
>> IBAL MAD processing threads may be in process of forwarding a
>> MAD and/or MAD processing with the outcome of eventually
>> accessing the HCA device. If the HCA is remove before AL
>> shutdown.....boom!