On Fri, Aug 11, 2017 at 8:07 PM, John Stultz <john.stultz@xxxxxxxxxx> wrote: > 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
