mpd client timeouts (bisected) 2.6.35-rc3

mpd client timeouts (bisected) 2.6.35-rc3

[Markus Trippelsdorf]

Commit 597a264b1a9c7e36d1728f677c66c5c1f7e3b837:
»net: deliver skbs on inactive slaves to exact matches«

causes large timeouts when mpd clients try to connect to a locally
running mpd (music player demon) on my machine. This makes it 
impossible to control mpd.

I bisected this down to the commit mentioned above.
Reverting the commit from 2.6.35-rc3 also solves the problem.

-- 
Markus

Re: mpd client timeouts (bisected) 2.6.35-rc3

[David Miller]

From: Markus Trippelsdorf <markus@trippelsdorf.de>
Date: Sat, 12 Jun 2010 12:28:02 +0200

> Commit 597a264b1a9c7e36d1728f677c66c5c1f7e3b837:
> »net: deliver skbs on inactive slaves to exact matches«
> 
> causes large timeouts when mpd clients try to connect to a locally
> running mpd (music player demon) on my machine. This makes it 
> impossible to control mpd.
> 
> I bisected this down to the commit mentioned above.
> Reverting the commit from 2.6.35-rc3 also solves the problem.

John, find an easy and fast way to fix this or else I am
going to revert.

Thanks.

Re: mpd client timeouts (bisected) 2.6.35-rc3

[John Fastabend]

David Miller wrote:
> From: Markus Trippelsdorf <markus@trippelsdorf.de>
> Date: Sat, 12 Jun 2010 12:28:02 +0200
> 
>> Commit 597a264b1a9c7e36d1728f677c66c5c1f7e3b837:
>> »net: deliver skbs on inactive slaves to exact matches«
>>
>> causes large timeouts when mpd clients try to connect to a locally
>> running mpd (music player demon) on my machine. This makes it 
>> impossible to control mpd.
>>
>> I bisected this down to the commit mentioned above.
>> Reverting the commit from 2.6.35-rc3 also solves the problem.
> 
> John, find an easy and fast way to fix this or else I am
> going to revert.
> 
> Thanks.

Looks like skbs are hitting loopback_xmit() with deliver_no_wcard set.  Then in 
the receive path these skbs are only delivered to exact matches.  Not sure why 
this bit is set here, I'll track this down first thing tomorrow.

Thanks,
John.

Re: mpd client timeouts (bisected) 2.6.35-rc3

[John Fastabend]

John Fastabend wrote:
> David Miller wrote:
>> From: Markus Trippelsdorf <markus@trippelsdorf.de>
>> Date: Sat, 12 Jun 2010 12:28:02 +0200
>>
>>> Commit 597a264b1a9c7e36d1728f677c66c5c1f7e3b837:
>>> »net: deliver skbs on inactive slaves to exact matches«
>>>
>>> causes large timeouts when mpd clients try to connect to a locally
>>> running mpd (music player demon) on my machine. This makes it 
>>> impossible to control mpd.
>>>
>>> I bisected this down to the commit mentioned above.
>>> Reverting the commit from 2.6.35-rc3 also solves the problem.
>> John, find an easy and fast way to fix this or else I am
>> going to revert.
>>
>> Thanks.
> 
> Looks like skbs are hitting loopback_xmit() with deliver_no_wcard set.  Then in 
> the receive path these skbs are only delivered to exact matches.  Not sure why 
> this bit is set here, I'll track this down first thing tomorrow.
> 
> Thanks,
> John.
> --

Needed to set the wcard bit in copy_skb_header otherwise it will not be cleared 
when called from skb_clone.  Which then hits the loopback device gets pushed 
into the rx path and is eventually dropped. The following patch fixes this. 
Hopefully, this is easy and fast enough for you Dave.


[PATCH] net: fix deliver_no_wcard regression on loopback device

deliver_no_wcard is not being set in skb_copy_header.
In the skb_cloned case it is not being cleared and
may cause the skb to be dropped when the loopback device
pushes it back up the stack.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
---

  net/core/skbuff.c |    1 +
  1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 9f07e74..bcf2fa3 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -532,6 +532,7 @@ static void __copy_skb_header(struct sk_buff *new, const 
struct sk_buff *old)
  	new->ip_summed		= old->ip_summed;
  	skb_copy_queue_mapping(new, old);
  	new->priority		= old->priority;
+	new->deliver_no_wcard	= old->deliver_no_wcard;
  #if defined(CONFIG_IP_VS) || defined(CONFIG_IP_VS_MODULE)
  	new->ipvs_property	= old->ipvs_property;
  #endif

Re: mpd client timeouts (bisected) 2.6.35-rc3

[Eric Dumazet]

Le dimanche 13 juin 2010 à 13:36 -0700, John Fastabend a écrit :
> John Fastabend wrote:
> > David Miller wrote:
> >> From: Markus Trippelsdorf <markus@trippelsdorf.de>
> >> Date: Sat, 12 Jun 2010 12:28:02 +0200
> >>
> >>> Commit 597a264b1a9c7e36d1728f677c66c5c1f7e3b837:
> >>> »net: deliver skbs on inactive slaves to exact matches«
> >>>
> >>> causes large timeouts when mpd clients try to connect to a locally
> >>> running mpd (music player demon) on my machine. This makes it 
> >>> impossible to control mpd.
> >>>
> >>> I bisected this down to the commit mentioned above.
> >>> Reverting the commit from 2.6.35-rc3 also solves the problem.
> >> John, find an easy and fast way to fix this or else I am
> >> going to revert.
> >>
> >> Thanks.
> > 
> > Looks like skbs are hitting loopback_xmit() with deliver_no_wcard set.  Then in 
> > the receive path these skbs are only delivered to exact matches.  Not sure why 
> > this bit is set here, I'll track this down first thing tomorrow.
> > 
> > Thanks,
> > John.
> > --
> 
> Needed to set the wcard bit in copy_skb_header otherwise it will not be cleared 
> when called from skb_clone.  Which then hits the loopback device gets pushed 
> into the rx path and is eventually dropped. The following patch fixes this. 
> Hopefully, this is easy and fast enough for you Dave.
> 
> 
> [PATCH] net: fix deliver_no_wcard regression on loopback device
> 
> deliver_no_wcard is not being set in skb_copy_header.
> In the skb_cloned case it is not being cleared and
> may cause the skb to be dropped when the loopback device
> pushes it back up the stack.
> 
> Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
> ---
> 
>   net/core/skbuff.c |    1 +
>   1 files changed, 1 insertions(+), 0 deletions(-)
> 
> diff --git a/net/core/skbuff.c b/net/core/skbuff.c
> index 9f07e74..bcf2fa3 100644
> --- a/net/core/skbuff.c
> +++ b/net/core/skbuff.c
> @@ -532,6 +532,7 @@ static void __copy_skb_header(struct sk_buff *new, const 
> struct sk_buff *old)
>   	new->ip_summed		= old->ip_summed;
>   	skb_copy_queue_mapping(new, old);
>   	new->priority		= old->priority;
> +	new->deliver_no_wcard	= old->deliver_no_wcard;
>   #if defined(CONFIG_IP_VS) || defined(CONFIG_IP_VS_MODULE)
>   	new->ipvs_property	= old->ipvs_property;
>   #endif
> --

Acked-by: Eric Dumazet <eric.dumazet@gmail.com>

BTW, David, it seems there is a double rxhash copy...

[PATCH] net: rxhash already set in __copy_skb_header

No need to copy rxhash again in __skb_clone()

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
---
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 9f07e74..a58e63b 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -569,7 +569,6 @@ static struct sk_buff *__skb_clone(struct sk_buff *n, struct sk_buff *skb)
 	C(len);
 	C(data_len);
 	C(mac_len);
-	C(rxhash);
 	n->hdr_len = skb->nohdr ? skb_headroom(skb) : skb->hdr_len;
 	n->cloned = 1;
 	n->nohdr = 0;

Re: mpd client timeouts (bisected) 2.6.35-rc3

[markus]

On Sun, Jun 13, 2010 at 01:36:30PM -0700, John Fastabend wrote:
> John Fastabend wrote:
> >David Miller wrote:
> >>From: Markus Trippelsdorf <markus@trippelsdorf.de>
> >>Date: Sat, 12 Jun 2010 12:28:02 +0200
> >>
> >>>Commit 597a264b1a9c7e36d1728f677c66c5c1f7e3b837:
> >>>»net: deliver skbs on inactive slaves to exact matches«
> >>>
> >>>causes large timeouts when mpd clients try to connect to a locally
> >>>running mpd (music player demon) on my machine. This makes it
> >>>impossible to control mpd.
> >>>
> >>>I bisected this down to the commit mentioned above.
> >>>Reverting the commit from 2.6.35-rc3 also solves the problem.
> >>John, find an easy and fast way to fix this or else I am
> >>going to revert.
> >>
> >>Thanks.
> >
> >Looks like skbs are hitting loopback_xmit() with deliver_no_wcard
> >set.  Then in the receive path these skbs are only delivered to
> >exact matches.  Not sure why this bit is set here, I'll track this
> >down first thing tomorrow.
> >
> >Thanks,
> >John.
> >--
> 
> Needed to set the wcard bit in copy_skb_header otherwise it will not
> be cleared when called from skb_clone.  Which then hits the loopback
> device gets pushed into the rx path and is eventually dropped. The
> following patch fixes this. Hopefully, this is easy and fast enough
> for you Dave.
> 
> 
> [PATCH] net: fix deliver_no_wcard regression on loopback device

This solves the problem here. Thanks.

Tested-by: Markus Trippelsdorf <markus@trippelsdorf.de>
-- 
Markus

Re: mpd client timeouts (bisected) 2.6.35-rc3

[David Miller]

From: John Fastabend <john.r.fastabend@intel.com>
Date: Sun, 13 Jun 2010 13:36:30 -0700

> Needed to set the wcard bit in copy_skb_header otherwise it will not
> be cleared when called from skb_clone.  Which then hits the loopback
> device gets pushed into the rx path and is eventually dropped. The
> following patch fixes this. Hopefully, this is easy and fast enough
> for you Dave.
> 
> 
> [PATCH] net: fix deliver_no_wcard regression on loopback device
> 
> deliver_no_wcard is not being set in skb_copy_header.
> In the skb_cloned case it is not being cleared and
> may cause the skb to be dropped when the loopback device
> pushes it back up the stack.
> 
> Signed-off-by: John Fastabend <john.r.fastabend@intel.com>

Applied, but your email client corrupted this patch in many
ways.  Please correct this for next time, thanks.

Re: mpd client timeouts (bisected) 2.6.35-rc3

[David Miller]

From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Sun, 13 Jun 2010 22:50:46 +0200

> Acked-by: Eric Dumazet <eric.dumazet@gmail.com>

Eric, please never ACK a patch in the same mail in which you are
posting new patch.  Patchwork won't add your ACK to the patchwork
entry you are ACK'ing because all of your text will go into a new
patchwork entry for the patch you are posting.

> BTW, David, it seems there is a double rxhash copy...
> 
> [PATCH] net: rxhash already set in __copy_skb_header
> 
> No need to copy rxhash again in __skb_clone()
> 
> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>

I'll apply this, thanks.

Re: mpd client timeouts (bisected) 2.6.35-rc3

[David Miller]

From: "markus@trippelsdorf.de" <markus@trippelsdorf.de>
Date: Sun, 13 Jun 2010 22:59:22 +0200

> On Sun, Jun 13, 2010 at 01:36:30PM -0700, John Fastabend wrote:
>> [PATCH] net: fix deliver_no_wcard regression on loopback device
> 
> This solves the problem here. Thanks.
> 
> Tested-by: Markus Trippelsdorf <markus@trippelsdorf.de>

Thanks for testing.

Re: mpd client timeouts (bisected) 2.6.35-rc3

[Michael S. Tsirkin]

On Sun, Jun 13, 2010 at 05:13:18PM -0700, David Miller wrote:
> From: John Fastabend <john.r.fastabend@intel.com>
> Date: Sun, 13 Jun 2010 13:36:30 -0700
> 
> > Needed to set the wcard bit in copy_skb_header otherwise it will not
> > be cleared when called from skb_clone.  Which then hits the loopback
> > device gets pushed into the rx path and is eventually dropped. The
> > following patch fixes this. Hopefully, this is easy and fast enough
> > for you Dave.
> > 
> > 
> > [PATCH] net: fix deliver_no_wcard regression on loopback device
> > 
> > deliver_no_wcard is not being set in skb_copy_header.
> > In the skb_cloned case it is not being cleared and
> > may cause the skb to be dropped when the loopback device
> > pushes it back up the stack.
> > 
> > Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
> 
> Applied, but your email client corrupted this patch in many
> ways.  Please correct this for next time, thanks.

FWIW:

Tested-by: Michael S. Tsirkin <mst@redhat.com>

-- 
MST

Re: mpd client timeouts (bisected) 2.6.35-rc3

[Christian Kujau]

On Sun, 13 Jun 2010 at 22:59, markus@trippelsdorf.de wrote:
> This solves the problem here. Thanks.

Not sure if this is related, but I've noticed connection timeouts and 
connections going in FIN_WAIT2 state (most of them SSH tunnels) with 
2.6.35. Going back to 2.6.34 or applying John's (and Eric's) patch 
does seem to fix this issue.

Thanks,
Christian.
-- 
BOFH excuse #168:

le0: no carrier: transceiver cable problem?

RE: mpd client timeouts (bisected) 2.6.35-rc3

[Shi, Alex]

It fixed the aim7/specjbb2005 issues! 

Tested-by: Alex Shi <alex.shi@intel.com>


Regards! 
Alex  

>
>Needed to set the wcard bit in copy_skb_header otherwise it will not be cleared
>when called from skb_clone.  Which then hits the loopback device gets pushed
>into the rx path and is eventually dropped. The following patch fixes this.
>Hopefully, this is easy and fast enough for you Dave.
>
>
>[PATCH] net: fix deliver_no_wcard regression on loopback device
>
>deliver_no_wcard is not being set in skb_copy_header.
>In the skb_cloned case it is not being cleared and
>may cause the skb to be dropped when the loopback device
>pushes it back up the stack.
>
>Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
>---
>
>  net/core/skbuff.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
>
>diff --git a/net/core/skbuff.c b/net/core/skbuff.c
>index 9f07e74..bcf2fa3 100644
>--- a/net/core/skbuff.c
>+++ b/net/core/skbuff.c
>@@ -532,6 +532,7 @@ static void __copy_skb_header(struct sk_buff *new, const
>struct sk_buff *old)
>  	new->ip_summed		= old->ip_summed;
>  	skb_copy_queue_mapping(new, old);
>  	new->priority		= old->priority;
>+	new->deliver_no_wcard	= old->deliver_no_wcard;
>  #if defined(CONFIG_IP_VS) || defined(CONFIG_IP_VS_MODULE)
>  	new->ipvs_property	= old->ipvs_property;
>  #endif

Re: mpd client timeouts (bisected) 2.6.35-rc3

[Christoph Fritz]

On Sun, 2010-06-13 at 22:59 +0200, markus@trippelsdorf.de wrote:
> On Sun, Jun 13, 2010 at 01:36:30PM -0700, John Fastabend wrote:

> > [PATCH] net: fix deliver_no_wcard regression on loopback device
> 
> This solves the problem here. Thanks.

here too

Tested-by: Christoph Fritz <chf.fritz@googlemail.com>