Re: [REGRESSION][4.13.y][4.14.y][v4.15.y] net: reduce skb_warn_bad_offload() noise

From: David Miller
Date: Tue Dec 12 2017 - 09:10:25 EST


From: Willem de Bruijn <willemdebruijn.kernel@xxxxxxxxx>
Date: Mon, 11 Dec 2017 16:56:56 -0500

> On Mon, Dec 11, 2017 at 4:44 PM, Greg Kroah-Hartman
> <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>> On Mon, Dec 11, 2017 at 04:25:26PM -0500, Willem de Bruijn wrote:
>>> Note that UFO was removed in 4.14 and that skb_warn_bad_offload
>>> can happen for various types of packets, so there may be multiple
>>> independent bug reports. I'm investigating two other non-UFO reports
>>> just now.
>>
>> Meta-comment, now that UFO is gone from mainline, I'm wondering if I
>> should just delete it from 4.4 and 4.9 as well. Any objections for
>> that? I'd like to make it easy to maintain these kernels for a while,
>> and having them diverge like this, with all of the issues around UFO,
>> seems like it will just make life harder for myself if I leave it in.
>>
>> Any opinions?
>
> Some of that removal had to be reverted with commit 0c19f846d582
> ("net: accept UFO datagrams from tuntap and packet") for VM live
> migration between kernels.
>
> Any backports probably should squash that in at the least. Just today
> another thread discussed that that patch may not address all open
> issues still, so it may be premature to backport at this point.
> http://lkml.kernel.org/r/<d71df64e-e65f-4db4-6f2e-c002c15fcbe4@xxxxxxxxxxxxxxx>

I would probably discourage backporting the UFO removal, at least for
now.