Date:   Thu, 18 Nov 2021 10:23:02 -0300
From:   Arnaldo Carvalho de Melo <acme@kernel.org>
To:     Daniel Borkmann <daniel@iogearbox.net>
Cc:     Andrii Nakryiko <andrii.nakryiko@gmail.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Alexei Starovoitov <ast@kernel.org>,
        Andrii Nakryiko <andrii@kernel.org>,
        Jiri Olsa <jolsa@redhat.com>, bpf <bpf@vger.kernel.org>,
        Networking <netdev@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 1/1] Documentation: Add minimum pahole version
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Em Wed, Nov 17, 2021 at 11:33:24PM +0100, Daniel Borkmann escreveu:
> On 11/16/21 7:21 PM, Andrii Nakryiko wrote:
> > On Tue, Nov 16, 2021 at 7:40 AM Arnaldo Carvalho de Melo
> > <acme@kernel.org> wrote:
> > > 
> > > A report was made in https://github.com/acmel/dwarves/issues/26 about
> > > pahole not being listed in the process/changes.rst file as being needed
> > > for building the kernel, address that.
> > > 
> > > Link: https://github.com/acmel/dwarves/issues/26
> > > Cc: Alexei Starovoitov <ast@kernel.org>
> > > Cc: Andrii Nakryiko <andrii@kernel.org>
> > > Cc: Daniel Borkmann <daniel@iogearbox.net>
> > > Cc: Jiri Olsa <jolsa@redhat.com>
> > > Cc: Jonathan Corbet <corbet@lwn.net>
> > > Cc: bpf@vger.kernel.org
> > > Cc: netdev@vger.kernel.org
> > > Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
> > > ---
> > >   Documentation/process/changes.rst | 9 +++++++++
> > >   1 file changed, 9 insertions(+)
> > > 
> > > diff --git a/Documentation/process/changes.rst b/Documentation/process/changes.rst
> > > index e35ab74a0f804b04..c45f167a1b6c02a4 100644
> > > --- a/Documentation/process/changes.rst
> > > +++ b/Documentation/process/changes.rst
> > > @@ -35,6 +35,7 @@ GNU make               3.81             make --version
> > >   binutils               2.23             ld -v
> > >   flex                   2.5.35           flex --version
> > >   bison                  2.0              bison --version
> > > +pahole                 1.16             pahole --version
> > >   util-linux             2.10o            fdformat --version
> > >   kmod                   13               depmod -V
> > >   e2fsprogs              1.41.4           e2fsck -V
> > > @@ -108,6 +109,14 @@ Bison
> > >   Since Linux 4.16, the build system generates parsers
> > >   during build.  This requires bison 2.0 or later.
> > > 
> > > +pahole:
> > > +-------
> > > +
> > > +Since Linux 5.2 the build system generates BTF (BPF Type Format) from DWARF in
> > > +vmlinux, a bit later from kernel modules as well, if CONFIG_DEBUG_INFO_BTF is
> > 
> > I'd probably emphasize a bit more that pahole is required only if
> > CONFIG_DEBUG_INFO_BTF is selected by moving "If CONFIG_DEBUG_INFO_BTF
> > is selected, " to the front. But either way looks good.
> 
> +1, I presume Jonathan will later pick up the v2?

I'll resubmit later.

- Arnaldo
 
> > Acked-by: Andrii Nakryiko <andrii@kernel.org>
> > 
> > > +selected.  This requires pahole v1.16 or later. It is found in the 'dwarves' or
> > > +'pahole' distro packages or from https://fedorapeople.org/~acme/dwarves/.
> > > +
> > >   Perl
> > >   ----
> > > 
> > > --
> > > 2.31.1
> > > 

-- 

- Arnaldo