Re: [PATCH rdma-next] RDMA/nldev: Fix section mismatch warning for nldev

Jason Gunthorpe
2022-10-28T16:16:41Z

On Fri, Oct 28, 2022 at 07:14:16PM +0300, Leon Romanovsky wrote:
> On Fri, Oct 28, 2022 at 01:00:27PM -0300, Jason Gunthorpe wrote:
> > On Fri, Oct 28, 2022 at 09:58:56AM +0300, Leon Romanovsky wrote:
> > > ppc64_defconfig) produced this warning:
> > >
> > > WARNING: modpost: drivers/infiniband/core/ib_core.o: section mismatch in reference: .init_module (section: .init.text) -> .nldev_exit (section: .exit.text)
> > >
> > > Fix it by removing __init/__exit markers as nldev is part of ib_core.ko
> > > and as such doesn't require any special notations for entry/exit functions.
> >
> > This isn't what the problem is, the patch Stephen reported:
> >
> > commit ad9394a3da33995dff828dbfd4540421e535bec9 (ko-rdma/for-rc)
> > Author: Chen Zhongjin <chenzhongjin@huawei.com>
> > Date: Tue Oct 25 10:41:46 2022 +0800
> >
> > RDMA/core: Fix null-ptr-deref in ib_core_cleanup()
> >
> > Adds a call to an __exit function from an __init function:
> >
> > @@ -2815,10 +2815,18 @@ static int __init ib_core_init(void)
> >
> > +err_parent:
> > + rdma_nl_unregister(RDMA_NL_LS);
> > + nldev_exit();
> > + unregister_pernet_device(&rdma_dev_net_ops);
> >
> > Which is not allowed
> >
> > All that is required is to drop the __exit from nldev_exit,
>
> This is why I dropped both __exit and __init. I see no value in keeping
> __init, without __exit.

__init works just fine, it will cause the code to be unload after the
module registration is compelted

__exit allows the code to be removed if the module is compiled in and
the __exit is never called

Jason