[PATCH] net_sched: long word align struct qdisc_skb_cb data

Eric Dumazet
2011-02-23T17:05:16Z

Le mercredi 23 février 2011 à 17:24 +0100, Patrick McHardy a écrit :
> Am 23.02.2011 16:14, schrieb Eric Dumazet:
> > diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
> > index 16626a0..f40d32e 100644
> > --- a/include/net/sch_generic.h
> > +++ b/include/net/sch_generic.h
> > @@ -218,6 +218,7 @@ struct tcf_proto {
> >
> > struct qdisc_skb_cb {
> > unsigned int pkt_len;
> > + unsigned int sfb_classid;
> > char data[];
> > };
>
> This could be moved into a SFB specific cb, similar to what netem
> does.

Hmm... well... I want to be sure no other sch will destroy my values.

netem seems buggy then.

Probably following patch is needed ?

Thanks

[PATCH] net_sched: long word align struct qdisc_skb_cb data

netem_skb_cb() does :

return (struct netem_skb_cb *)qdisc_skb_cb(skb)->data;

Unfortunatly struct qdisc_skb_cb data is not long word aligned, so
access to psched_time_t time_to_send uses a non aligned access.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
---
include/net/sch_generic.h | 2 +-
1 files changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index 16626a0..dbdf2b5 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -218,7 +218,7 @@ struct tcf_proto {

struct qdisc_skb_cb {
unsigned int pkt_len;
- char data[];
+ long data[];
};

static inline int qdisc_qlen(struct Qdisc *q)