On Fri, Aug 11, 2017 at 5:31 PM, John Stultz <john.stultz@xxxxxxxxxx> wrote: > On Fri, Aug 11, 2017 at 5:10 PM, Wei Wang <weiwan@xxxxxxxxxx> wrote: >>> If after Cong's fix, the issue still happens, could you help try the >>> patch attached and collect all logs when you try the reproduce the >>> issue? It would be great to have logs for both success case and the >>> failure case. >>> >>> Thanks so much for your help. >>> >> >> I think we have a potential fix for this issue. >> Martin and I found that when addrconf_dst_alloc() creates a rt6, it is >> possible that rt6->dst.dev points to loopback device while >> rt6->rt6i_idev->dev points to a real device. >> When the real device goes down, the current fib6 clean up code only >> checks for rt6->dst.dev and assumes rt6->rt6i_idev->dev is the same. >> That leaves unreleased refcnt on the real device if rt6->dst.dev >> points to loopback dev. >> >> The attached potential fix is tested by Martin and made sure it fixes his issue. >> >> John, >> It will be great if you can also give it a try and see if it fixes the >> issue on your side before I submit an official patch. > > So yes, sorry I haven't been able to get back quicker on the other > patches sent, was mucking about in other work. > > So yea, this patch (potential fix for unregister_netdevice()) seems > to avoid the issue. > > I'm going to do some further testing, but its looking good so far. Looks good so far! I've not hit the issue yet. Thanks so much for sorting out a fix! If its useful: Tested-by: John Stultz <john.stultz@xxxxxxxxxx> thanks again -john -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
