On Tue, 2017-05-09 at 15:52 -0700, Eric Dumazet wrote:
> On Tue, 2017-05-09 at 15:07 -0700, Cong Wang wrote:
> > On Tue, May 9, 2017 at 1:56 PM, Cong Wang <xiyou.wangc...@gmail.com> wrote:
> > > Wait... if we transfer dst->dev to loopback_dev because we don't
> > > want to block unregister path, then we might have a similar problem
> > > for rt->fi too, fib_info is still referenced by dst, so these nh_dev's
> > > still
> > > hold the dev references...
> > >
> >
> > I finally come up with the attach patch... Do you mind to give it a try?
>
> I will, but this might be delayed by a few hours.
>
> In the mean time, it looks like you could try adding the following to
> your .config ;)
>
> CONFIG_IP_ROUTE_MULTIPATH=y
>
>
+ /* This should be fine, we are on unregister
+ * path so synchronize_net() already waits for
+ * existing readers. We have to release the
+ * dev here because dst could still hold this
+ * fib_info via rt->fi, we can't wait for GC.
+ */
+ RCU_INIT_POINTER(nexthop_nh->nh_dev, NULL);
+ dev_put(dev);
dead = fi->fib_nhs;
dead = fi->fib_mhs looks wrong if you remove the break; statement ?
- break;
}
