From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <stephen@networkplumber.org>
Subject: Re: [PATCH net] hv_netvsc: preserve hw_features on
 mtu/channels/ringparam changes
Date: Tue, 14 Nov 2017 08:34:57 -0800
Message-ID: <20171114083457.5ec8c4f0@xeon-e3>
References: <20171114152205.10943-1-vkuznets@redhat.com>
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Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        devel@linuxdriverproject.org,
        "K. Y. Srinivasan" <kys@microsoft.com>,
        Haiyang Zhang <haiyangz@microsoft.com>,
        Stephen Hemminger <sthemmin@microsoft.com>,
        Mohammed Gamal <mmorsy@redhat.com>
To: Vitaly Kuznetsov <vkuznets@redhat.com>
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On Tue, 14 Nov 2017 16:22:05 +0100
Vitaly Kuznetsov <vkuznets@redhat.com> wrote:

Yes, this looks like a real issue.



> +	/* Query hardware capabilities if we're called from netvsc_probe() */
> +	if (!net->hw_features) {
> +		ret = rndis_netdev_set_hwcaps(net_device, rndis_device);
> +		if (ret != 0)
> +			goto err_dev_remv;
> +	}
> +

Rather than conditional behavior in rndis_filter_device_add, it would be cleaner
to make the call to get hardware capabilities there.

Please respin and make the query of host a separate function.