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Date:   Fri, 30 Sep 2022 07:19:51 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Edward Cree <ecree.xilinx@gmail.com>
Cc:     netdev@vger.kernel.org, linux-net-drivers@amd.com,
        davem@davemloft.net, pabeni@redhat.com, edumazet@google.com,
        habetsm.xilinx@gmail.com
Subject: Re: [PATCH v2 net-next 3/6] sfc: optional logging of TC offload
 errors
Message-ID: <20220930071951.61f81da6@kernel.org>
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On Fri, 30 Sep 2022 10:03:01 +0100 Edward Cree wrote:
> On 29/09/2022 02:15, Jakub Kicinski wrote:
> > Hm. I wonder if throwing a tracepoint into the extack setting
> > machinery would be a reasonable stop gap for debugging.  
> 
> It has one (do_trace_netlink_extack()), but sadly that won't play
>  so well with formatted extacks since AIUI trace needs a constant
>  string (I'm just giving it the format string in my prototype).
> But yeah it's better than nothing.

We can add a new one which copies the data. Presumably we'd have a "set
an extack msg which needs to be freed" helper were we could place it?
It'd mean we cut off at a static length but good enough, I say.