From mboxrd@z Thu Jan  1 00:00:00 1970
From: Or Gerlitz <ogerlitz@mellanox.com>
Subject: Re: [PATCH net-next V3 1/2] IB/ipoib: Add rtnl_link_ops support
Date: Thu, 13 Sep 2012 13:54:59 +0300
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Cc: Rami Rosen <roszenrami@gmail.com>,
	Patrick McHardy <kaber@trash.net>, <netdev@vger.kernel.org>,
	Shlomo Pongratz <shlomop@mellanox.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On 12/09/2012 18:13, Eric Dumazet wrote:
> It might be related to module load/unload udevd or some external 
> daemon can access sysfs files while you unload the module 

Hi Eric,

I see, the IPoIB add/delete child sysfs handlers (ipoib_vlan_add/delete) 
use
RTNL locking to protect against netdev changes while the handlers are in 
action.

IPoIB uses devide_create_file to add the sysfs entries, but doesn't care 
to use
device_remove_file as these entries sit under the netdevice 
/sys/class/net/DEV
directory and are removed by higher layer when DEV gets 
unregistered/deleted, I'm
not sure if/how the driver is supposed to protect against access to 
these entries
while going down, when the module is unloaded, etc, any idea will be 
appreciated.


Or.