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Date:   Wed, 4 Sep 2019 15:41:40 -0700
From:   Stephen Hemminger <stephen@networkplumber.org>
To:     Hui Peng <benquike@gmail.com>
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Subject: Re: WARNING in hso_free_net_device
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On Wed, 4 Sep 2019 16:27:50 -0400
Hui Peng <benquike@gmail.com> wrote:

> Hi, all:
>=20
> I looked at the bug a little.
>=20
> The issue is that in the error handling code, hso_free_net_device
> unregisters
>=20
> the net_device (hso_net->net)=C2=A0 by calling unregister_netdev. In the
> error handling code path,
>=20
> hso_net->net has not been registered yet.
>=20
> I think there are two ways to solve the issue:
>=20
> 1. fix it in drivers/net/usb/hso.c to avoiding unregistering the
> net_device when it is still not registered
>=20
> 2. fix it in unregister_netdev. We can add a field in net_device to
> record whether it is registered, and make unregister_netdev return if
> the net_device is not registered yet.
>=20
> What do you guys think ?

#1