On Sat, Feb 3, 2018 at 1:15 PM, Xin Long <lucien.xin@xxxxxxxxx> wrote: >>> On 1/30/18 1:57 PM, David Ahern wrote: >>>> On 1/30/18 1:08 PM, Daniel Borkmann wrote: >>>>> On 01/30/2018 07:32 PM, Cong Wang wrote: >>>>>> On Tue, Jan 30, 2018 at 4:09 AM, Dmitry Vyukov <dvyukov@xxxxxxxxxx> wrote: >>>>>>> Hello, >>>>>>> >>>>>>> The following program creates a hang in unregister_netdevice. >>>>>>> cleanup_net work hangs there forever periodically printing >>>>>>> "unregister_netdevice: waiting for lo to become free. Usage count = 3" >>>>>>> and creation of any new network namespaces hangs forever. >>>>>> >>>>>> Interestingly, this is not reproducible on net-next. >>>>> >>>>> The most recent change on netns refcnt was 4ee806d51176 ("net: tcp: close >>>>> sock if net namespace is exiting") in net/net-next from 5 days ago, maybe >>>>> fixed due to that? >>>>> >>>> >>>> This appears to be the commit introducing the refcnt leak: >>>> >>>> $ git bisect bad >>>> dbc2b5e9a09e9a6664679a667ff81cff6e5f2641 is the first bad commit >>>> commit dbc2b5e9a09e9a6664679a667ff81cff6e5f2641 >>>> Author: Xin Long <lucien.xin@xxxxxxxxx> >>>> Date: Fri May 12 14:39:52 2017 +0800 >>>> >>>> sctp: fix src address selection if using secondary addresses for ipv6 >>>> >>>> >>>> v4.14 is bad. Running bisect in the background while doing other things.... >>>> >>> >>> Interesting. The commit that avoids the refcnt leak is >>> >>> commit 955ec4cb3b54c7c389a9f830be7d3ae2056b9212 >>> Author: David Ahern <dsahern@xxxxxxxxx> >>> Date: Wed Jan 24 19:45:29 2018 -0800 >>> >>> net/ipv6: Do not allow route add with a device that is down >>> >>> That commit does not intentionally address the problem so it is just >>> masking the problematic code introduced by the commit above. >> Thanks, David A. >> >> I'm still on a trip. will look into this asap. > > Alexey and Tommi already had the patches for this issue on > both SCTP v4 and v6 dst_get, Thanks. Is this meant to be fixed already? I am still seeing this on the latest upstream tree. -- To unsubscribe from this list: send the line "unsubscribe linux-sctp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html