Date:   Mon, 6 Mar 2023 10:12:34 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     "Michael S. Tsirkin" <mst@redhat.com>
Cc:     Jason Wang <jasowang@redhat.com>, rbradford@rivosinc.com,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Paolo Abeni <pabeni@redhat.com>,
        virtualization@lists.linux-foundation.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3] virtio-net: Fix probe of virtio-net on kvmtool
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On Sun, 5 Mar 2023 04:53:58 -0500 Michael S. Tsirkin wrote:
> > > yes what we do work according to code.  So the documentation is wrong then?  
> > 
> > It's definitely incomplete but which part are you saying is wrong?  
> 
> So it says:
>   2. netdev->features set contains features which are currently enabled
>      for a device.
> 
> ok so far.
> But this part:
> 
>   This should be changed only by network core or in
>      error paths of ndo_set_features callback.
> 
> seems to say virtio should not touch netdev->features, no?

Oh, I see, yes. We should add a mention of ndo_fix_features there,
and perhaps "see Part II for more information"?.

The sentence reads like someone was trying to make sure drivers don't
silently change features without calling netdev_update_features().