Re: [ethtool] ethtool: Remove UDP Fragmentation Offload use from ethtool

On 29/08/2017 1:44 PM, Michal Kubecek wrote:

On Tue, Aug 29, 2017 at 10:50:20AM +0300, Tariq Toukan wrote:

quoted

On 28/08/2017 9:22 PM, John W. Linville wrote:

quoted

On Mon, Aug 28, 2017 at 08:00:11AM -0700, Eric Dumazet wrote:

quoted

On Mon, 2017-08-28 at 15:38 +0300, Tariq Toukan wrote:

quoted

From: Shaker Daibes <redacted>

UFO was removed in kernel, here we remove it in ethtool app.

Fixes the following issue:
Features for ens8:
Cannot get device udp-fragmentation-offload settings: Operation not supported

But I wonder how the warning removal should be done??

I have some suggestions in mind:
1) Have a special condition that does not print a warning only in the case
of UFO?
2) Remove the warning totally? I don't like this option.
3) Add a max_kernel_ver field in struct off_flag_def, and use it to not
print the warning, or to mark the feature 'off [fixed]'.

IMHO there is nothing wrong with not writing a warning for "get"
operation, after all it's just "ethtool -k", i.e. "show me all
offloading flags" and we do not warn about unsupported named features
either. IMHO the only question should be how friendly we should be to
old scripts expecting the line in the output:

   (a) omit the "udp-fragmentation-offload:" line (be consistent)
   (b) say something like "udp-fragmentation-offload: n/a"
   (c) pretend it's there and is off (most careful but misleading)

Personally, I would prefer (a) but some badly written scripts might have
problem with this approach.

Thanks Michal.
I think we'll go for some variation of (a), omitting the warning.
Here we can choose to limit the omission for this exact case, i.e. only when offload is UFO and err is "Operation not supported".

On the other hand, an attempt to _set_ the flag with "ethtool -K" should
issue an error.

Michal Kubecek