lkml.org 
[lkml]   [2019]   [Jan]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [BUG] moving fq back to clock monotonic breaks my setup
From
Date
On Thu, 2019-01-10 at 09:25 +0100, Ian Kumlien wrote:
> On Thu, Jan 10, 2019 at 6:53 AM Eric Dumazet <edumazet@google.com> wrote:
> > On Wed, Jan 9, 2019 at 4:48 PM Ian Kumlien <ian.kumlien@gmail.com> wrote:
> > > Hi,
> > >
> > > Just been trough ~5+ hours of bisecting and eventually actually found
> > > the culprit =)
> > >
> > > commit fb420d5d91c1274d5966917725e71f27ed092a85 (refs/bisect/bad)
> > > Author: Eric Dumazet <edumazet@google.com>
> > > Date: Fri Sep 28 10:28:44 2018 -0700
> > >
> > > tcp/fq: move back to CLOCK_MONOTONIC
> > >
> > > [--8<--]
> > >
> > > So this might be because my setup might be "odd".
> > >
> > > Basically I have a firewall with four nics that uses two of those nics
> > > to handle my normal
> > > internet connection (firewall/MASQ/NAT) and the other two are assigned
> > > to one bridge each.
> > >
> > > The firewall is also my local caching DNS server and DHCP server,
> > > which is also used by the VM:s...
> > > But with 4.20 DHCP replies disappeared before entering the bridge - i
> > > couldn't even see them in
> > > tcpdump! (all nics are ixgbe on a atom soc)
> > >
> > > I'm currently running a kernel with that patch reversed but I'm also
> > > wondering about possible ways
> > > forward since I'm reverting a fix from someone else...
> >
> > I suggest you use netdev@ mailing list instead of lkml
> >
> > Then, we probably need to clear skb->tstamp in more paths (you are
> > mentioning bridge ...)
> >
> > See commit 8203e2d844d34af247a151d8ebd68553a6e91785 for reference.
> >
> > Can you try :
> >
> > diff --git a/net/bridge/br_forward.c b/net/bridge/br_forward.c
> > index 5372e2042adfe20d3cd039c29057535b2413be61..bd4fa141420c92a44716bd93fcd8aa3d3310203a
> > 100644
> > --- a/net/bridge/br_forward.c
> > +++ b/net/bridge/br_forward.c
> > @@ -53,6 +53,7 @@ int br_dev_queue_push_xmit(struct net *net, struct
> > sock *sk, struct sk_buff *skb
> > skb_set_network_header(skb, depth);
> > }
> >
> > + skb->tstamp = 0;
> > dev_queue_xmit(skb);
> >
> > return 0;
>
> This works, and so does: https://marc.info/?l=linux-netdev&m=154696956604748&w=2
>
> Pointed out by Paolo (tested both separately)

Note: I cleared the tstamp in br_forward_finish() instead of
br_dev_queue_push_xmit() because I think the latter could be called
also in the local xmit path, via br_nf_post_routing.

We must preserve the tstamp in output path, right?

Thanks,

Paolo




\
 
 \ /
  Last update: 2019-01-10 09:55    [W:0.064 / U:7.608 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site