netdev - Re: [PATCH take 2] pkt_sched: Fix qdisc_watchdog() vs. dev

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Thu, 11 Sep 2008 12:10:10 +0000
From:	Jarek Poplawski <jarkao2@...il.com>
To:	Herbert Xu <herbert@...dor.apana.org.au>
Cc:	David Miller <davem@...emloft.net>, netdev@...r.kernel.org
Subject: Re: [PATCH take 2] pkt_sched: Fix qdisc_watchdog() vs.
	dev_deactivate() race

On Thu, Sep 11, 2008 at 09:54:49PM +1000, Herbert Xu wrote:
> On Thu, Sep 11, 2008 at 11:51:32AM +0000, Jarek Poplawski wrote:
> > 
> > IMHO, the most reasonable test here is for all tx_queues of a qdisc
> > beeing stopped, but since this is quite heavy, probably we need an
> > additional qdisc flag for such an occasion.
> 
> Yes we could do that too.  Although the head-of-qdisc approach
> will eventually lead to the same result.  That is, as you pop
> things off the head eventually you'll hit a packet that belongs
> to the stopped queue and that'll then block the whole qdisc.
> 
> So I don't think there's anything inherently advantageous in
> checking all the queues.

Yes, but this is only because this current behaviour of blocking all
transmit by one stopped tx_queue is wrong (IMHO), and with sch_multiq
there should be a real advantage.

Cheers,
Jarek P.
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html