[ofa-general] RE: [PATCH] CMA: Enable conn_id remove

[Vladimir Sokolovsky]

Sean Hefty wrote:
>>>> I have the following issue: The IB driver can't be unloaded after 
>>>> running
>>>> applications over RDS.
>>>
>> Yes, HCA driver and there are active connections when the driver is 
>> unloaded.
> 
> At least from looking at the code, it looks like unloading the device 
> driver with connections on the passive side should hang.  I'm updating 
> my test code to verify that this is the case, but can you confirm that 
> this problem is easily reproducible using RDS?
> 

Yes, it is easily reproducible:

I have 2 servers with MT25418 HCAs (mlx4) connected to the IB switch.
Driver removal hangs on one of them every time if RDS connection was active
(run rds-stress test, for example, to create the connection).

- Vladimir

> I'm guessing that most of my device removal testing was always done from 
> the active side, and none of the mainline kernel ULPs call 
> rdma_listen().  I'm hoping this would explain why this bug has gone 
> undetected for this long.
> 
> - Sean
>