linux-toradex.git/net/sched, branch v2.6.18.3

PKT_SCHED: cls_basic: Use unsigned int when generating handle

2006-10-13T20:23:27+00:00

gcc-4.1 and later take advantage of the fact that in the
C language certain types of overflow/underflow are undefined,
and this is completely legitimate.

Prevents filters from being added if the first generated
handle already exists.

Signed-off-by: Kim Nordlund 
Signed-off-by: Thomas Graf 
Signed-off-by: Greg Kroah-Hartman

NET_SCHED: Fix fallout from dev->qdisc RCU change

2006-10-13T20:23:20+00:00

The move of qdisc destruction to a rcu callback broke locking in the
entire qdisc layer by invalidating previously valid assumptions about
the context in which changes to the qdisc tree occur.

The two assumptions were:

- since changes only happen in process context, read_lock doesn't need
  bottem half protection. Now invalid since destruction of inner qdiscs,
  classifiers, actions and estimators happens in the RCU callback unless
  they're manually deleted, resulting in dead-locks when read_lock in
  process context is interrupted by write_lock_bh in bottem half context.

- since changes only happen under the RTNL, no additional locking is
  necessary for data not used during packet processing (f.e. u32_list).
  Again, since destruction now happens in the RCU callback, this assumption
  is not valid anymore, causing races while using this data, which can
  result in corruption or use-after-free.

Instead of "fixing" this by disabling bottem halfs everywhere and adding
new locks/refcounting, this patch makes these assumptions valid again by
moving destruction back to process context. Since only the dev->qdisc
pointer is protected by RCU, but ->enqueue and the qdisc tree are still
protected by dev->qdisc_lock, destruction of the tree can be performed
immediately and only the final free needs to happen in the rcu callback
to make sure dev_queue_xmit doesn't access already freed memory.

Signed-off-by: Patrick McHardy 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

[NET]: Drop tx lock in dev_watchdog_up

2006-09-18T07:22:30+00:00

Fix lockdep warning with GRE, iptables and Speedtouch ADSL, PPP over ATM.

On Sat, Sep 02, 2006 at 08:39:28PM +0000, Krzysztof Halasa wrote:
> 
> =======================================================
> [ INFO: possible circular locking dependency detected ]
> -------------------------------------------------------
> swapper/0 is trying to acquire lock:
>  (&dev->queue_lock){-+..}, at: [] dev_queue_xmit+0x56/0x290
> 
> but task is already holding lock:
>  (&dev->_xmit_lock){-+..}, at: [] dev_queue_xmit+0x224/0x290
> 
> which lock already depends on the new lock.

This turns out to be a genuine bug.  The queue lock and xmit lock are
intentionally taken out of order.  Two things are supposed to prevent
dead-locks from occuring:

1) When we hold the queue_lock we're supposed to only do try_lock on the
tx_lock.

2) We always drop the queue_lock after taking the tx_lock and before doing
anything else.

> 
> the existing dependency chain (in reverse order) is:
> 
> -> #1 (&dev->_xmit_lock){-+..}:
>        [] lock_acquire+0x76/0xa0
>        [] _spin_lock_bh+0x31/0x40
>        [] dev_activate+0x69/0x120

This path obviously breaks assumption 1) and therefore can lead to ABBA
dead-locks.

I've looked at the history and there seems to be no reason for the lock
to be held at all in dev_watchdog_up.  The lock appeared in day one and
even there it was unnecessary.  In fact, people added __dev_watchdog_up
precisely in order to get around the tx lock there.

The function dev_watchdog_up is already serialised by rtnl_lock since
its only caller dev_activate is always called under it.

So here is a simple patch to remove the tx lock from dev_watchdog_up.
In 2.6.19 we can eliminate the unnecessary __dev_watchdog_up and
replace it with dev_watchdog_up.

Signed-off-by: Herbert Xu 
Signed-off-by: David S. Miller

[PKT_SCHED] cls_u32: Fix typo.

2006-08-17T23:29:54+00:00

Signed-off-by: Ralf Hildebrandt 
Signed-off-by: David S. Miller

[PKT_SCHED]: Return ENOENT if qdisc module is unavailable

2006-08-05T05:59:49+00:00

Return ENOENT if qdisc module is unavailable

Signed-off-by: Jamal Hadi Salim 
Signed-off-by: David S. Miller

[NET]: Conversions from kmalloc+memset to k(z|c)alloc.

2006-07-21T21:51:30+00:00

Signed-off-by: Panagiotis Issaris 
Signed-off-by: David S. Miller

[PKT_SCHED] netem: Fix slab corruption with netem (2nd try)

2006-07-21T21:45:25+00:00

CONFIG_DEBUG_SLAB found the following bug:
netem_enqueue() in sch_netem.c gets a pointer inside a slab object:
struct netem_skb_cb *cb = (struct netem_skb_cb *)skb->cb;
But then, the slab object may be freed:
skb = skb_unshare(skb, GFP_ATOMIC)
cb is still pointing inside the freed skb, so here is a patch to
initialize cb later, and make it clear that initializing it sooner
is a bad idea.

[From Stephen Hemminger: leave cb unitialized in order to let gcc
complain in case of use before initialization]

Signed-off-by: Guillaume Chazarain 
Signed-off-by: David S. Miller

[PATCH] sch_htb compile fix.

2006-07-15T18:40:20+00:00

net/sched/sch_htb.c: In function 'htb_change_class':
net/sched/sch_htb.c:1605: error: expected ';' before 'do_gettimeofday'

Signed-off-by: Dave Jones 
Signed-off-by: Linus Torvalds

[PKT_SCHED] HTB: initialize upper bound properly

2006-07-14T23:32:27+00:00

The upper bound for HTB time diff needs to be scaled to PSCHED
units rather than just assuming usecs.  The field mbuffer is used
in TDIFF_SAFE(), as an upper bound.

Signed-off-by: Stephen Hemminger 
Acked-by: Jamal Hadi Salim 
Signed-off-by: David S. Miller

[MAINTAINERS]: Add proper entry for TC classifier

2006-07-12T20:58:48+00:00

Acked-by: Jamal Hadi Salim 
Signed-off-by: David S. Miller