Subject: Re: pandaboard brctl oops

From: Shan Wei <[email-masked]>
Date: Tue, 02 Aug 2011 10:24:22 +0800

hi

Marek Vasut wrote, at 08/02/2011 05:25 AM:
> Hi,
> 
> recently a friend of mine sent me this backtrace. I put him in CC so please any 
> subsequent questions shall be forwarded to him.
> 
> He claims this happens on pandaboard.
> 
> Cheers
> 
> root@box:~# brctl addbr br0
> root@box:~# brctl addif br0 eth0
> [   77.795776] Unable to handle kernel NULL pointer dereference at virtual 
> address 00000000
> [   77.804321] pgd = ee8d4000
> [   77.807312] [00000000] *pgd=af8e6831, *pte=00000000, *ppte=00000000
> [   77.813995] Internal error: Oops: 80000007 [#1] SMP
> [   77.819122] last sysfs file: /sys/devices/virtual/net/br0/uevent
> [   77.825439] Modules linked in: bridge stp llc wl12xx_sdio wl12xx
> [   77.831787] CPU: 0    Not tainted  (2.6.39.2-omap4 #3)
> [   77.837188] PC is at 0x0
> [   77.839904] LR is at br_change_mtu+0x64/0x7c [bridge]

This one has been fixed in latest kernel.

commit 6407d74c5106bb362b4087693688afd34942b094
Author: Alexander Holler <[email-masked]>
Date:   Tue Jun 7 00:51:35 2011 -0700

    bridge: provide a cow_metrics method for fake_ops
    
    Like in commit 0972ddb237 (provide cow_metrics() methods to blackhole
    dst_ops), we must provide a cow_metrics for bridges fake_dst_ops as
    well.
    
    This fixes a regression coming from commits 62fa8a846d7d (net: Implement
    read-only protection and COW'ing of metrics.) and 33eb9873a28 (bridge:
    initialize fake_rtable metrics)
    
    ip link set mybridge mtu 1234

-- 
Best Regards
-----
Shan Wei