netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Michal Soltys <soltys@ziu.info>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: netdev@vger.kernel.org, bugme-daemon@bugzilla.kernel.org,
	Jamal Hadi Salim <hadi@cyberus.ca>,
	lucas.bocchi@gmail.com, Patrick McHardy <kaber@trash.net>,
	631945@bugs.debian.org, 00bormoj@gmail.com,
	fdelawarde@wirelessmundi.com
Subject: Bug#631945: [Bugme-new] [Bug 39372] New: Problems with HFSC Scheduler
Date: Fri, 29 Jul 2011 14:29:10 +0200	[thread overview]
Message-ID: <4E32A796.8060104@ziu.info> (raw)
In-Reply-To: <20110714151425.844b7738.akpm@linux-foundation.org>

On 11-07-15 00:14, Andrew Morton wrote:
> 
> (switched to email.  Please respond via emailed reply-to-all, not via
> the bugzilla web interface).
> 
> 
> Here: WARN_ON(next_time == 0);
> 

>From the other thread on netfilter-devel:

> On 11-07-22 11:58, Michal Pokrywka wrote: After bisecting 2.6.39.1 it
> turned out that the bug is caused independently by two patches:
> 
> commit b262a5da755cc6ed0cb4fba230cd9bf4037e1096 sch_sfq: fix peek()
> implementation
> 
> and
> 
> commit 9df49f2bfe862573911a080c75a6d81113c5c81d sch_sfq: avoid giving
> spurious NET_XMIT_CN signals
> 
> Reverting these patches makes HFSC work again.
> 

This one (upstream 8efa885406359af300d46910642b50ca82c0fe47) seems to be
the culprit (does reverting only that one cures the problem ?)

It allows SFQ to return success on enqueuing, when the packet really
replaced some other packet in some other flow. This confuses outer qdisc
(in this particular case HFSC) which thinks new packet was actually
added each time such situation happes.

This in turn causes additional dequeues and ends with attempt
to schedule non-existent packets, and triggers the warning.


ps.

removed netfilter from cc, as it's not really netfilter issue.

  reply	other threads:[~2011-07-29 12:29 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <bug-39372-10286@https.bugzilla.kernel.org/>
2011-07-14 22:14 ` [Bugme-new] [Bug 39372] New: Problems with HFSC Scheduler Andrew Morton
2011-07-29 12:29   ` Michal Soltys [this message]
2011-07-29 13:27     ` Eric Dumazet
2011-07-29 14:00       ` Eric Dumazet
2011-07-29 14:11         ` Patrick McHardy
2011-07-30  5:22           ` Eric Dumazet
2011-08-01  9:27             ` David Miller
2011-08-04 13:55 Bug#631945: " Michal Pokrywka

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=4E32A796.8060104@ziu.info \
    --to=soltys@ziu.info \
    --cc=00bormoj@gmail.com \
    --cc=631945@bugs.debian.org \
    --cc=akpm@linux-foundation.org \
    --cc=bugme-daemon@bugzilla.kernel.org \
    --cc=fdelawarde@wirelessmundi.com \
    --cc=hadi@cyberus.ca \
    --cc=kaber@trash.net \
    --cc=lucas.bocchi@gmail.com \
    --cc=netdev@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).