From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vlad Yasevich Subject: Re: [PATCH 3/4] sctp: fix association hangs due to errors when reneging events from the ordering queue Date: Wed, 27 Feb 2013 08:53:04 -0500 Message-ID: <512E0FC0.4070502@gmail.com> References: <1361889376-22171-1-git-send-email-lee.roberts@hp.com> <1361889376-22171-4-git-send-email-lee.roberts@hp.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: "Lee A. Roberts" Return-path: Received: from mail-ye0-f170.google.com ([209.85.213.170]:59508 "EHLO mail-ye0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760001Ab3B0Oxe (ORCPT ); Wed, 27 Feb 2013 09:53:34 -0500 Received: by mail-ye0-f170.google.com with SMTP id m15so75246yen.29 for ; Wed, 27 Feb 2013 06:53:33 -0800 (PST) In-Reply-To: <1361889376-22171-4-git-send-email-lee.roberts@hp.com> Sender: netdev-owner@vger.kernel.org List-ID: On 02/26/2013 09:36 AM, Lee A. Roberts wrote: > From: "Lee A. Roberts" > > Resolve SCTP association hangs observed during SCTP stress > testing. Observable symptoms include communications hangs > with data being held in the association reassembly and/or lobby > (ordering) queues. Close examination of reassembly queue shows > missing packets. > > In sctp_ulpq_renege_list(), events being reneged from the > ordering queue may correspond to multiple TSNs. Identify > all affected packets; sum freed space and renege from the > tsnmap. > > Signed-off-by: Lee A. Roberts Acked-by: Vlad Yasevich -vlad > --- > net/sctp/ulpqueue.c | 26 ++++++++++++++++++++++---- > 1 file changed, 22 insertions(+), 4 deletions(-) > > diff --git a/net/sctp/ulpqueue.c b/net/sctp/ulpqueue.c > index 63afddc..f221fbb 100644 > --- a/net/sctp/ulpqueue.c > +++ b/net/sctp/ulpqueue.c > @@ -962,8 +962,8 @@ static __u16 sctp_ulpq_renege_list(struct sctp_ulpq *ulpq, > struct sk_buff_head *list, __u16 needed) > { > __u16 freed = 0; > - __u32 tsn; > - struct sk_buff *skb; > + __u32 tsn, last_tsn; > + struct sk_buff *skb, *flist, *last; > struct sctp_ulpevent *event; > struct sctp_tsnmap *tsnmap; > > @@ -977,10 +977,28 @@ static __u16 sctp_ulpq_renege_list(struct sctp_ulpq *ulpq, > if (TSN_lte(tsn, sctp_tsnmap_get_ctsn(tsnmap))) > break; > > - __skb_unlink(skb, list); > + /* Events in ordering queue may have multiple fragments > + * corresponding to additional TSNs. Sum the total > + * freed space; find the last TSN. > + */ > freed += skb_headlen(skb); > + flist = skb_shinfo(skb)->frag_list; > + for (last = flist; flist; flist = flist->next) { > + last = flist; > + freed += skb_headlen(last); > + } > + if (last) > + last_tsn = sctp_skb2event(last)->tsn; > + else > + last_tsn = tsn; > + > + /* Unlink the event, then renege all applicable TSNs. */ > + __skb_unlink(skb, list); > sctp_ulpevent_free(event); > - sctp_tsnmap_renege(tsnmap, tsn); > + while (TSN_lte(tsn, last_tsn)) { > + sctp_tsnmap_renege(tsnmap, tsn); > + tsn++; > + } > if (freed >= needed) > return freed; > } >