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Date: Tue, 09 Sep 2014 11:03:02 +0800
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Subject: Re: [Qemu-devel] [PATCH] net: don't use set/get_pointer() in
	set/get_netdev()
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To: Peter Maydell <peter.maydell@linaro.org>, Stefan Hajnoczi <stefanha@gmail.com>
Cc: Markus Armbruster <armbru@redhat.com>, =?UTF-8?B?QW5kcmVhcyBGw6RyYmVy?= <afaerber@suse.de>, qemu-devel <qemu-devel@nongnu.org>, Stefan Hajnoczi <stefanha@redhat.com>, "Michael S. Tsirkin" <mst@redhat.com>

On 09/05/2014 12:40 AM, Peter Maydell wrote:
> On 4 September 2014 17:21, Stefan Hajnoczi <stefanha@gmail.com> wrote:
>> Unfortunately this patch breaks aarch64-softmmu qtests:
>> GTESTER check-qtest-aarch64
>> Broken pipe
>> GTester: last random seed: R02S6d8ab263ca56f8ae7a4b47bdf93fbc73
>>
>> Please take a look at what is causing this.
> Specifically, it breaks on all the ARM boards which have
> more than one built in ethernet device. Something in your
> patch is probably assuming there is only one (there's
> a somewhat suspicious "[0]" array reference, for instance).
>
> thanks
> -- PMM
>

The '[0]' dereference was introduced after multiqueue is supported.
Since there may be multiple pairs of peers for each nic.

The failure reason looks like the ncs[0] pointer should be validated
before trying to access them.

Will post V2.

Thanks