[PATCH 1/1] Documentation: Add minimum pahole version

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 <redacted>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: bpf@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <redacted>
---
 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
+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

On Tue, Nov 16, 2021 at 7:40 AM Arnaldo Carvalho de Melo
[off-list ref] wrote:

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.

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

On 11/16/21 7:21 PM, Andrii Nakryiko wrote:

On Tue, Nov 16, 2021 at 7:40 AM Arnaldo Carvalho de Melo
[off-list ref] wrote:

quoted

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 <redacted>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: bpf@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <redacted>
---
  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?

Acked-by: Andrii Nakryiko <andrii@kernel.org>

quoted

+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

Em Wed, Nov 17, 2021 at 11:33:24PM +0100, Daniel Borkmann escreveu:

On 11/16/21 7:21 PM, Andrii Nakryiko wrote:

quoted

On Tue, Nov 16, 2021 at 7:40 AM Arnaldo Carvalho de Melo
[off-list ref] wrote:

quoted

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 <redacted>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: bpf@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <redacted>
---
  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
 

quoted

Acked-by: Andrii Nakryiko <andrii@kernel.org>

quoted

+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