This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
Home Products Support Community News


Re: [Xen-devel] Null-pointer access in netback_uevent

To: Bastian Blank <waldi@xxxxxxxxxx>, James Harper <james.harper@xxxxxxxxxxxxxxxx>, xen-devel@xxxxxxxxxxxxxxxxxxx
Subject: Re: [Xen-devel] Null-pointer access in netback_uevent
From: Jeremy Fitzhardinge <jeremy@xxxxxxxx>
Date: Fri, 28 May 2010 10:28:16 -0700
Delivery-date: Fri, 28 May 2010 10:29:09 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <20100528090325.GA13575@xxxxxxxxxxxxxxxxxxxxxxx>
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
References: <20100527165558.GA11358@xxxxxxxxxxxxxxxxxxxxxxx> <AEC6C66638C05B468B556EA548C1A77D01996BD8@trantor> <AEC6C66638C05B468B556EA548C1A77D01996BDB@trantor> <AEC6C66638C05B468B556EA548C1A77D01996BE0@trantor> <20100528090325.GA13575@xxxxxxxxxxxxxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv: Gecko/20100430 Fedora/3.0.4-2.fc12 Lightning/1.0b2pre Thunderbird/3.0.4
On 05/28/2010 02:03 AM, Bastian Blank wrote:
> On Fri, May 28, 2010 at 10:47:48AM +1000, James Harper wrote:
>>>> I noticed this just after I posted (subject "oops starting domain on 4.0.0
>>>> +"). I'm getting the same error.
>>> Actually my error is occurring because 'be' is NULL in netback_uevent (eg
>>> dev_get_drvdata returns NULL)
>> Looking into this further, I suspect that the trigger here is a newer 
>> version of udev or something in that area. netback_uevent is getting called 
>> before the call to netback_probe containing the call to dev_set_drvdata.
> There are two problems there. And yes, the uevent routine can be called
> at any time.

So would it be correct for it to just return if either of those are
NULL?  Will it get called again later once the device info is available?


Xen-devel mailing list