Re: [PATCH v3 00/14] Adding GAUDI NIC code to habanalabs driver

[Greg Kroah-Hartman]

On Wed, Sep 16, 2020 at 09:36:23AM +0300, Oded Gabbay wrote:
> On Wed, Sep 16, 2020 at 9:25 AM Greg Kroah-Hartman
> <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> >
> > On Tue, Sep 15, 2020 at 11:49:12PM +0300, Oded Gabbay wrote:
> > > On Tue, Sep 15, 2020 at 11:42 PM David Miller <davem@xxxxxxxxxxxxx> wrote:
> > > >
> > > > From: Oded Gabbay <oded.gabbay@xxxxxxxxx>
> > > > Date: Tue, 15 Sep 2020 20:10:08 +0300
> > > >
> > > > > This is the second version of the patch-set to upstream the GAUDI NIC code
> > > > > into the habanalabs driver.
> > > > >
> > > > > The only modification from v2 is in the ethtool patch (patch 12). Details
> > > > > are in that patch's commit message.
> > > > >
> > > > > Link to v2 cover letter:
> > > > > https://lkml.org/lkml/2020/9/12/201
> > > >
> > > > I agree with Jakub, this driver definitely can't go-in as it is currently
> > > > structured and designed.
> > > Why is that ?
> > > Can you please point to the things that bother you or not working correctly?
> > > I can't really fix the driver if I don't know what's wrong.
> > >
> > > In addition, please read my reply to Jakub with the explanation of why
> > > we designed this driver as is.
> > >
> > > And because of the RDMA'ness of it, the RDMA
> > > > folks have to be CC:'d and have a chance to review this.
> > > As I said to Jakub, the driver doesn't use the RDMA infrastructure in
> > > the kernel and we can't connect to it due to the lack of H/W support
> > > we have
> > > Therefore, I don't see why we need to CC linux-rdma.
> > > I understood why Greg asked me to CC you because we do connect to the
> > > netdev and standard eth infrastructure, but regarding the RDMA, it's
> > > not really the same.
> >
> > Ok, to do this "right" it needs to be split up into separate drivers,
> > hopefully using the "virtual bus" code that some day Intel will resubmit
> > again that will solve this issue.
> Hi Greg,
> Can I suggest an alternative for the short/medium term ?
> 
> In an earlier email, Jakub said:
> "Is it not possible to move the files and still build them into a single
> module?"
> 
> I thought maybe that's a good way to progress here ?

Cross-directory builds of a single module are crazy.  Yes, they work,
but really, that's a mess, and would never suggest doing that.

> First, split the content to Ethernet and RDMA.
> Then move the Ethernet part to drivers/net but build it as part of
> habanalabs.ko.
> Regarding the RDMA code, upstream/review it in a different patch-set
> (maybe they will want me to put the files elsewhere).
> 
> What do you think ?

I think you are asking for more work there than just splitting out into
separate modules :)

thanks,

greg k-h