netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Patrick McHardy <kaber@trash.net>
To: hadi@cyberus.ca
Cc: Jarek Poplawski <jarkao2@o2.pl>,
	netdev@vger.kernel.org, Dave Jones <davej@redhat.com>,
	davem@davemloft.net
Subject: Re: tc related lockdep warning.
Date: Mon, 25 Sep 2006 15:29:10 +0200	[thread overview]
Message-ID: <4517D9A6.70307@trash.net> (raw)
In-Reply-To: <1159188473.5301.68.camel@jzny2>

jamal wrote:
> On Mon, 2006-25-09 at 14:43 +0200, Jarek Poplawski wrote:
> 
> 
>>It's probably 2.6.18 and should change a little now (git4) but
>>IMHO main problem stays: it looks tcf_act_police_locate in
>>act_police.c was preempted in read_lock (tcf_police_lookup)
>>- now the same is possible in tcf_hash_lookup. So maybe
>>read_lock_bh will help?
>>
> 
> 
> Yes, that looks plausible. Can you try making those changes and see if
> the warning is gone?


I think this points to a bigger brokeness caused by the move of
dev->qdisc to RCU. It means destruction of filters and actions doesn't
necessarily happens in user-context and thus not protected by the rtnl
anymore. On first sight all actions are affected by this, as well as
the u32 classifier (race between u32_destroy and u32_init while changing
u32_list), but I bet there are more. I'm busy right now, but I'll look
into this later.


  parent reply	other threads:[~2006-09-25 13:29 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-09-24 21:29 tc related lockdep warning Dave Jones
2006-09-25 12:43 ` Jarek Poplawski
2006-09-25 12:47   ` jamal
2006-09-25 13:05     ` Jarek Poplawski
2006-09-25 13:29     ` Patrick McHardy [this message]
2006-09-26 16:15       ` Patrick McHardy
2006-09-26 21:20         ` Dave Jones
2006-09-27  8:54           ` Jarek Poplawski
2006-09-27  9:57             ` Patrick McHardy
2006-09-28 12:17             ` Patrick McHardy
2006-09-28 13:13               ` Jarek Poplawski
2006-09-28 14:20                 ` Stephen Hemminger
2006-09-29  6:28                   ` Jarek Poplawski
2006-09-27 10:14           ` Patrick McHardy
2006-09-27 14:41             ` Ismail Donmez
2006-09-27 12:07           ` Patrick McHardy
2006-09-27 17:26             ` Ismail Donmez
2006-09-27 17:33             ` Dave Jones
2006-09-27 23:53             ` David Miller
2006-09-28  9:07               ` Jarek Poplawski
2006-09-28  8:17             ` Jarek Poplawski

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=4517D9A6.70307@trash.net \
    --to=kaber@trash.net \
    --cc=davej@redhat.com \
    --cc=davem@davemloft.net \
    --cc=hadi@cyberus.ca \
    --cc=jarkao2@o2.pl \
    --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).