From: Wolfgang Walter <wolfgang.walter@studentenwerk.mhn.de>
Organization: Studentenwerk =?iso-8859-1?q?M=FCnchen?=
To: "David S. Miller" <davem@davemloft.net>
Subject: Re: Bad: scheduling while atomic! in 2.6.8.1
Date: Thu, 9 Sep 2004 13:56:47 +0200
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Am Donnerstag, 9. September 2004 06:26 schrieb David S. Miller:
> On Wed, 8 Sep 2004 23:42:37 +0200
>
> Wolfgang Walter <wolfgang.walter@studentenwerk.mhn.de> wrote:
> > We see the exactly the same with 2.6.8.1.
> >
> > Our host has 3 nics (all 3 are intel e100). We are using vlan, iptables
> > (no nat or connection tracking, though) and ipsec. We tested it on other
> > hardware (different mainboard, different nics) and the problem remains.
> >
> > We are getting the log for every received packet, doesn't matter if these
> > are dhcp-requests, pings or something else.
>
> You have CONFIG_PREEMPT enabled don't you?
>

Yes.

> This should fix it, it's a bug in Stephen's conversion of the VLAN
> code over to use RCU locking.
>
> # This is a BitKeeper generated diff -Nru style patch.
> #
> # ChangeSet
> #   2004/09/08 21:07:49-07:00 davem@nuts.davemloft.net
> #   [VLAN]: Fix thinko in RCU locking.
> #
> #   Signed-off-by: David S. Miller <davem@davemloft.net>
> #
> # net/8021q/vlan_dev.c
> #   2004/09/08 21:07:19-07:00 davem@nuts.davemloft.net +1 -1
> #   [VLAN]: Fix thinko in RCU locking.
> #
> diff -Nru a/net/8021q/vlan_dev.c b/net/8021q/vlan_dev.c
> --- a/net/8021q/vlan_dev.c 2004-09-08 21:08:30 -07:00
> +++ b/net/8021q/vlan_dev.c 2004-09-08 21:08:30 -07:00
> @@ -244,7 +244,7 @@
>     /* TODO:  Add a more specific counter here. */
>     stats->rx_errors++;
>    }
> -  rcu_read_lock();
> +  rcu_read_unlock();
>    return 0;
>   }

Yes, this fixes the problem.

Thank you very much,

-- 
Wolfgang Walter
Studentenwerk München
Anstalt des öffentlichen Rechts
EDV
Leopoldstraße 15
80802 München
http://www.studentenwerk.mhn.de/