Re: [PATCH] Fix netdev_printk null dereference

[David Miller <davem@davemloft.net>]

From: Joe Perches <joe@perches.com>
Date: Fri, 05 Mar 2010 06:50:20 -0800

> On Fri, 2010-03-05 at 06:39 -0800, David Miller wrote:
>> From: Steve Glendinning <steve.glendinning@smsc.com>
>> Date: Fri,  5 Mar 2010 12:47:05 +0000
>> 
>> > This patch fixes a reproducible null dereference in smsc95xx (and I
>> > suspect others) when the device is removed during a control register
>> > access.  This can be reproduced by rapidly plugging and unplugging
>> > the device during its initialisation.
>> > 
>> > Signed-off-by: Steve Glendinning <steve.glendinning@smsc.com>
>> 
>> The parent shouldn't become NULL until the device is totally quiesced
>> and is no longer accesses.
>> 
>> Maybe you can instead fix the smsc95xx driver to abide by this rule
>> instead of adding a conditional check to thousands of other drivers in
>> the tree that do not need this?
>> 
>> I really have no intention of adding your change, please fix this
>> properly, thanks.
>> --
>> To unsubscribe from this list: send the line "unsubscribe netdev" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 
> Perhaps something like this is appropriate in the mean time:
> 
> const char *get_netdev_parent_name(const struct net_device *dev)
> {
> 	if (!dev->dev.parent)
> 		return "Unparented net_device, please report this";
> 	return netdev->dev.parent;
> }

Yes,  but in the smsc95xx driver. :-)