Re: [PATCH] IB: Revert "remove redundant INFINIBAND kconfig dependencies"

[Greg Thelen]

Jason Gunthorpe <jgg@xxxxxxxx> wrote:

> On Fri, May 25, 2018 at 05:32:52PM -0700, Greg Thelen wrote:
> > On Fri, May 25, 2018 at 2:32 PM Arnd Bergmann <arnd@xxxxxxxx> wrote:

> > > Several subsystems depend on INFINIBAND_ADDR_TRANS, which in turn  
> > depends
> > > on INFINIBAND. However, when with CONFIG_INIFIBAND=m, this leads to a
> > > link error when another driver using it is built-in. The
> > > INFINIBAND_ADDR_TRANS dependency is insufficient here as this is
> > > a 'bool' symbol that does not force anything to be a module in turn.

> > > fs/cifs/smbdirect.o: In function `smbd_disconnect_rdma_work':
> > > smbdirect.c:(.text+0x1e4): undefined reference to `rdma_disconnect'
> > > net/9p/trans_rdma.o: In function `rdma_request':
> > > trans_rdma.c:(.text+0x7bc): undefined reference to `rdma_disconnect'
> > > net/9p/trans_rdma.o: In function `rdma_destroy_trans':
> > > trans_rdma.c:(.text+0x830): undefined reference to `ib_destroy_qp'
> > > trans_rdma.c:(.text+0x858): undefined reference to `ib_dealloc_pd'

> > > Fixes: 9533b292a7ac ("IB: remove redundant INFINIBAND kconfig
> > dependencies")
> > > Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>

> > Acked-by: Greg Thelen <gthelen@xxxxxxxxxx>

> > Sorry for the 9533b292a7ac problem.
> > At this point the in release cycle, I think Arnd's revert is best.

> > If there is interest, I've put a little thought into an alternative fix:
> > making INFINIBAND_ADDR_TRANS tristate.  But it's nontrivial.
> > So I prefer this simple revert for now.

> Is that a normal thing to do?

For me: no, it's not normal.  In my use case I merely want to disable
INFINIBAND_ADDR_TRANS while continuing to use INFINIBAND.  This is
supported with f7cb7b85be55 ("IB: make INFINIBAND_ADDR_TRANS
configurable").

During f7cb7b85be55 development https://lkml.org/lkml/2018/4/30/1073
suggested that we drop dependency on both INFINIBAND and
INFINIBAND_ADDR_TRANS.  Thus 9533b292a7ac ("IB: remove redundant
INFINIBAND kconfig dependencies").

But 9533b292a7ac led to the randconfig build errors reported and thus
("IB: Revert "remove redundant INFINIBAND kconfig dependencies"").

So I see no need to do anything more than apply ("IB: Revert "remove
redundant INFINIBAND kconfig dependencies"").

> > Doug: do you need anything from me on this?

> I can take the revert..

> Jason

Thanks.