Re: [RFC] Proposal to address hfi1 UI and EPROM devices

Dennis Dalessandro
2016-05-03T16:54:05Z

On Tue, May 03, 2016 at 07:24:57PM +0300, Leon Romanovsky wrote:
>On Mon, May 02, 2016 at 03:55:02PM -0400, Dennis Dalessandro wrote:
>> We also should be able to use any of these schemes to handle our eprom
>> reading/writing. Adding eprom to IPoIB as Doug suggested is a fine plan, but
>> we technically don't need to do it right now when we could make do with the
>> "UI" functionality and hide the details in user space. In the future there
>> may well be value in having an eprom capability in the rdma sub-system, but
>> for now we believe we can avoid extending the kernel in this regard.
>
>Just to understand better your RFC. Are you asking from the community
>excuse do not implement core functionality just because you don't need
>it? Am I right?

The purpose of the RFC is to get the community's feedback on our plans to
solve our UI/EPROM issue. The paragraphs [1] not snipped in your response
focus on that. It comes down to:

Use resource0 which does not support locking vs use a file in
/sys/kernel/debug.

The point of the particular paragraph you are questioning is that I don't
think we should add more code and complexity to the kernel for something
that is not needed.

[1] http://marc.info/?l=linux-rdma&m=146221891012428&w=2

-Denny