Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Mon, 26 Jun 2023 14:53:53 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Namhyung Kim <namhyung@kernel.org>
Cc:     Matthieu Baerts <matthieu.baerts@tessares.net>,
        David Howells <dhowells@redhat.com>, netdev@vger.kernel.org,
        Arnaldo Carvalho de Melo <acme@redhat.com>,
        David Miller <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Paolo Abeni <pabeni@redhat.com>, Jens Axboe <axboe@kernel.dk>,
        Matthew Wilcox <willy@infradead.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Jiri Olsa <jolsa@kernel.org>, Ian Rogers <irogers@google.com>,
        Adrian Hunter <adrian.hunter@intel.com>,
        linux-perf-users@vger.kernel.org, bpf@vger.kernel.org,
        linux-next@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH net-next] tools: Fix MSG_SPLICE_PAGES build error in
 trace tools
Message-ID: <20230626145353.468fd133@kernel.org>
In-Reply-To: <CAM9d7ch_mWUQGW8G221bZmCPn3wB2mjZm=ZdmhDkczhich9xZA@mail.gmail.com>
References: <5791ec06-7174-9ae5-4fe4-6969ed110165@tessares.net>
        <3065880.1687785614@warthog.procyon.org.uk>
        <3067876.1687787456@warthog.procyon.org.uk>
        <2cb3b411-9010-a44b-ebee-1914e7fd7b9c@tessares.net>
        <CAM9d7ch_mWUQGW8G221bZmCPn3wB2mjZm=ZdmhDkczhich9xZA@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Precedence: bulk

On Mon, 26 Jun 2023 14:31:39 -0700 Namhyung Kim wrote:
> Right, we want to keep the headers files in the tools in sync with
> the kernel ones.  And they are used to generate some tables.
> Full explanation from Arnaldo below.
> 
> So I'm ok for the msg_flags.c changes, but please refrain from
> changing the header directly.  We will update it later.
> 
> With that,
>   Acked-by: Namhyung Kim <namhyung@kernel.org>

Ah, missed this email, sounds like this is preferred to Matthieu's
fix, we'll take this one.

> Also I wonder if the tool needs to keep the original flag
> (SENDPAGE_NOTLAST) for the older kernels.

That's a bit unclear, because it's just a kernel-internal flag.
Future kernels may well use that bit for something else.

Better long term solution would be to use an enum so that the values
are included in debuginfo and perf can read them at runtime :(