[PATCH] Re: [BUG] DEADLOCK when removing a bridge on 2.4.19-pre6

[Mike Fedyk <mfedyk@matchmail.com>]

On Wed, Apr 10, 2002 at 06:40:35PM -0700, Mike Fedyk wrote:
> On Wed, Apr 10, 2002 at 06:05:15PM -0700, Mike Fedyk wrote:
> > On Wed, Apr 10, 2002 at 05:49:11PM -0700, Mike Fedyk wrote:
> > > 2.4.18_fix_port_state_handling.diff
> > > 
> > > Is causing the problem on 2.4.17-19p6tulip-br0fpsh.  I haven't tested the
> > > other patches though.
> > > 
> > > I'm going to reverse this patch on 2.4.19-pre6 to see if it fixes it there
> > > too.  Stay tuned.
> > 
> > 2.4.18_enslave_bridge_dev_to_bridge_dev.diff
> > 
> > Is fine I didn't reproduce the trouble in 2.4.17-19p6tulip-br0ebdtbd (it was
> > already compiling when I tested the port_state kernel...).
> > 
> > 2.4.19-pre6-nobr0fpsh building now...
> 
> Yep, reversing 2.4.18_fix_port_state_handling.diff fixed it.
> 

Instead of reversing the patch, use this patch from Lennert Buytenhek instead:

Note: this problem should only show up on smp kernels(unvarified), it showed
up with a smp kernel on a UP system for me.

--- linux-2.4.18/net/bridge/br_input.c.orig	Thu Apr 18 11:50:16 2002
+++ linux-2.4.18/net/bridge/br_input.c	Thu Apr 18 11:50:26 2002
@@ -161,8 +161,10 @@
 handle_special_frame:
 	if (!dest[5]) {
 		br_stp_handle_bpdu(skb);
+		read_unlock(&br->lock);
 		return;
 	}
 
+	read_unlock(&br->lock);
 	kfree_skb(skb);
 }