netdev - Re: [PATCH]: Schedule correct qdisc in watchdog.

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]

Message-Id: <20080818.031003.115715822.davem@davemloft.net>
Date:	Mon, 18 Aug 2008 03:10:03 -0700 (PDT)
From:	David Miller <davem@...emloft.net>
To:	jarkao2@...il.com
Cc:	netdev@...r.kernel.org
Subject: Re: [PATCH]: Schedule correct qdisc in watchdog.

From: Jarek Poplawski <jarkao2@...il.com>
Date: Mon, 18 Aug 2008 09:47:27 +0000

> Maybe I wrote this wrong. wd->qdisc stores qdisc from the
> qdisc_watchdog_init() time, and this could be &noop_qdisc.
> So qdisc_root() would schedule wrong qdisc later. BTW, my
> version would probably do the same for root qdisc, but in
> these tests there was a problem with leafs.

qdisc_watchdog_init() is only invoked by:

net/sched/sch_cbq.c:	qdisc_watchdog_init(&q->watchdog, sch);
net/sched/sch_hfsc.c:	qdisc_watchdog_init(&q->watchdog, sch);
net/sched/sch_htb.c:	qdisc_watchdog_init(&q->watchdog, sch);
net/sched/sch_netem.c:	qdisc_watchdog_init(&q->watchdog, sch);
net/sched/sch_tbf.c:	qdisc_watchdog_init(&q->watchdog, sch);

These "q" things are the scheduler private structs, and 'sch' of the
qdisc type indicated by the source file the code in question resides
:-)

This watchdog is different from the TX timeout watchdog which is
implemented in net/sch/sch_generic.c, which you may be confusing this
qdisc_watchdog_init() one with.

The watchdog we are discussing here is purely for qdiscs where time
based events modify qdisc state (such as making new quotas available
for a flow, thus making certain packets eligible for scheduling that
were not beforehand)

So really, it cannot be &noop_qdisc as far as I can see.
:-)
--
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