[PATCH] kbuild: rpm-pkg: Preserve .BTF section in kernel modules during debuginfo stripping

[PATCH] kbuild: rpm-pkg: Preserve .BTF section in kernel modules during debuginfo stripping

[Yafang Shao]

After switching to the kernel's default package scripts for our local
kernel RPM builds, we noticed that module BTF entries were missing:

  $ ls /sys/kernel/btf/
  vmlinux    <<<< only vmlinux, no module BTF

Root cause: find-debuginfo.sh (from the debugedit package) prefers
eu-strip over strip when elfutils is installed, which is the common
case on RHEL 9. eu-strip removes non-allocated ELF sections, including
the .BTF section that contains BPF Type Format information for kernel
modules. Without .BTF, BPF tools (bpftool, bcc, bpftrace) cannot resolve
kernel types at runtime, and /sys/kernel/btf/<module> entries are not
created when modules are loaded.

Fix by passing --keep-section .BTF via _find_debuginfo_opts, which adds
-K .BTF to the eu-strip/strip command, preserving the .BTF section while
allowing normal debuginfo extraction to proceed.

After this change, all module BTF files are properly generated:

  $ ls /sys/kernel/btf/
  aesni_intel         drm                 i2c_i801            mfd_core
  ahci                drm_client_lib      i2c_mux             net_failover
  backlight           drm_kms_helper      i2c_smbus           pcspkr
  ccp                 drm_shmem_helper    input_leds          qemu_fw_cfg
  dm_log              failover            intel_rapl_common   sch_fq_codel
  dm_mirror           fat                 intel_rapl_msr      serio_raw
  dm_mod              fuse                irqbypass           sunrpc
  dm_region_hash      gf128mul            iTCO_wdt            vfat
  virtio_balloon      virtio_console      virtio_dma_buf      virtio_gpu
  virtio_net          virtio_rng          virtio_blk          vmlinux
  xfs

Assisted-by: Comagic:DeepSeek-V4-Flash
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
---
 scripts/package/kernel.spec | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/package/kernel.spec b/scripts/package/kernel.spec
index c732415662ef..abc73de019e0 100644
--- a/scripts/package/kernel.spec
+++ b/scripts/package/kernel.spec
@@ -67,7 +67,7 @@ This package provides debug information for the kernel image and modules from th
 %undefine _unique_debug_srcs
 %undefine _debugsource_packages
 %undefine _debuginfo_subpackages
-%global _find_debuginfo_opts -r
+%global _find_debuginfo_opts -r --keep-section .BTF
 %global _missing_build_ids_terminate_build 1
 %global _no_recompute_build_ids 1
 %{debug_package}
-- 
2.52.0

[PATCH] kbuild: rpm-pkg: append %{?dist} macro to Release tag

[Yafang Shao]

Add support for the %{?dist} macro in the kernel.spec file. This enables
building and releasing kernel RPMs with a custom distribution suffix
(e.g., via rpmbuild's --define option) to better match production
environment tracking.

Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
---
 scripts/package/kernel.spec | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/package/kernel.spec b/scripts/package/kernel.spec
index b3c956205af0..c732415662ef 100644
--- a/scripts/package/kernel.spec
+++ b/scripts/package/kernel.spec
@@ -6,7 +6,7 @@
 Name: kernel
 Summary: The Linux Kernel
 Version: %(echo %{KERNELRELEASE} | sed -e 's/-/_/g')
-Release: %{pkg_release}
+Release: %{pkg_release}%{?dist}
 License: GPL
 Group: System Environment/Kernel
 Vendor: The Linux Community
-- 
2.47.3

Re: [PATCH] kbuild: rpm-pkg: append %{?dist} macro to Release tag

[Yafang Shao]

On Sun, Jul 12, 2026 at 2:29 PM Yafang Shao <laoar.shao@gmail.com> wrote:
>
> Add support for the %{?dist} macro in the kernel.spec file. This enables
> building and releasing kernel RPMs with a custom distribution suffix
> (e.g., via rpmbuild's --define option) to better match production
> environment tracking.
>
> Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
> ---
>  scripts/package/kernel.spec | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/scripts/package/kernel.spec b/scripts/package/kernel.spec
> index b3c956205af0..c732415662ef 100644
> --- a/scripts/package/kernel.spec
> +++ b/scripts/package/kernel.spec
> @@ -6,7 +6,7 @@
>  Name: kernel
>  Summary: The Linux Kernel
>  Version: %(echo %{KERNELRELEASE} | sed -e 's/-/_/g')
> -Release: %{pkg_release}
> +Release: %{pkg_release}%{?dist}
>  License: GPL
>  Group: System Environment/Kernel
>  Vendor: The Linux Community
> --
> 2.47.3
>

oops!
Apologies for the confusion. Please disregard the patch, as it was an
accepted patch accidentally included in the same directory and sent
alongside the intended one:

  https://lore.kernel.org/linux-kbuild/20260712062834.77872-1-laoar.shao@gmail.com/


--
Regards
Yafang

[PATCH] kbuild: rpm-pkg: append %{?dist} macro to Release tag

[Yafang Shao]

Add support for the %{?dist} macro in the kernel.spec file. This enables
building and releasing kernel RPMs with a custom distribution suffix
(e.g., via rpmbuild's --define option) to better match production
environment tracking.

Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
---
 scripts/package/kernel.spec | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/package/kernel.spec b/scripts/package/kernel.spec
index b3c956205af0..c732415662ef 100644
--- a/scripts/package/kernel.spec
+++ b/scripts/package/kernel.spec
@@ -6,7 +6,7 @@
 Name: kernel
 Summary: The Linux Kernel
 Version: %(echo %{KERNELRELEASE} | sed -e 's/-/_/g')
-Release: %{pkg_release}
+Release: %{pkg_release}%{?dist}
 License: GPL
 Group: System Environment/Kernel
 Vendor: The Linux Community
-- 
2.47.3

Re: [PATCH] kbuild: rpm-pkg: append %{?dist} macro to Release tag

[Nathan Chancellor]

On Tue, 26 May 2026 14:27:32 +0800, Yafang Shao <laoar.shao@gmail.com> wrote:
> diff --git a/scripts/package/kernel.spec b/scripts/package/kernel.spec
> index b3c956205af0..c732415662ef 100644
> --- a/scripts/package/kernel.spec
> +++ b/scripts/package/kernel.spec
> @@ -6,7 +6,7 @@
>  Name: kernel
>  Summary: The Linux Kernel
>  Version: %(echo %{KERNELRELEASE} | sed -e 's/-/_/g')
> -Release: %{pkg_release}
> +Release: %{pkg_release}%{?dist}

This seems reasonable at face value, especially since Fedora recommends
this for all of its packages but the value of dist will be included in
the version string with how this is currently written:

  $ make -skj"$(nproc)" ARCH=x86_64 RPMOPTS="--define 'dist .distval123'" mrproper defconfig rpm-pkg
  ...

  $ cat include/generated/utsversion.h
  #define UTS_VERSION "#1.distval123 SMP PREEMPT_DYNAMIC Wed May 27 17:27:34 MST 2026"

Maybe that's fine (or even considered a feature)? Figured it was worth
pointing out in case anyone can think of problems from allowing this.
Another option could be just changing

  KBUILD_BUILD_VERSION=%{release}

to

  KBUILD_BUILD_VERSION=%{pkg_release}

to avoid this.

-- 
Cheers,
Nathan

Re: [PATCH] kbuild: rpm-pkg: append %{?dist} macro to Release tag

[Yafang Shao]

On Thu, May 28, 2026 at 8:43 AM Nathan Chancellor <nathan@kernel.org> wrote:
>
> On Tue, 26 May 2026 14:27:32 +0800, Yafang Shao <laoar.shao@gmail.com> wrote:
> > diff --git a/scripts/package/kernel.spec b/scripts/package/kernel.spec
> > index b3c956205af0..c732415662ef 100644
> > --- a/scripts/package/kernel.spec
> > +++ b/scripts/package/kernel.spec
> > @@ -6,7 +6,7 @@
> >  Name: kernel
> >  Summary: The Linux Kernel
> >  Version: %(echo %{KERNELRELEASE} | sed -e 's/-/_/g')
> > -Release: %{pkg_release}
> > +Release: %{pkg_release}%{?dist}
>
> This seems reasonable at face value, especially since Fedora recommends
> this for all of its packages but the value of dist will be included in
> the version string with how this is currently written:
>
>   $ make -skj"$(nproc)" ARCH=x86_64 RPMOPTS="--define 'dist .distval123'" mrproper defconfig rpm-pkg
>   ...
>
>   $ cat include/generated/utsversion.h
>   #define UTS_VERSION "#1.distval123 SMP PREEMPT_DYNAMIC Wed May 27 17:27:34 MST 2026"
>
> Maybe that's fine (or even considered a feature)?

I believe the current behavior is fine because the 'dist' value is
properly displayed in the `uname -a` output, as shown below:

  $ uname -a
  Linux localhost.localdomain 7.1.0-rc5+ #1.distval123 SMP
PREEMPT_DYNAMIC Thu May 28 06:25:23 UTC 2026 x86_64 x86_64 x86_64
GNU/Linux

However, if we apply the change below, the 'dist' value will be
omitted from the `uname -a` output:

  $ uname -a
  Linux localhost.localdomain 7.1.0-rc5+ #2 SMP PREEMPT_DYNAMIC Thu
May 28 07:43:05 UTC 2026 x86_64 x86_64 x86_64 GNU/Linux

> Figured it was worth
> pointing out in case anyone can think of problems from allowing this.
> Another option could be just changing
>
>   KBUILD_BUILD_VERSION=%{release}
>
> to
>
>   KBUILD_BUILD_VERSION=%{pkg_release}
>
> to avoid this.
>
> --
> Cheers,
> Nathan
>


-- 
Regards
Yafang

Re: [PATCH] kbuild: rpm-pkg: append %{?dist} macro to Release tag

[Nathan Chancellor]

On Tue, 26 May 2026 14:27:32 +0800, Yafang Shao wrote:
> kbuild: rpm-pkg: append %{?dist} macro to Release tag

Applied to

  https://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux.git kbuild-next

Thanks!

[1/1] kbuild: rpm-pkg: append %{?dist} macro to Release tag
      https://git.kernel.org/kbuild/c/159921d63da16

Please look out for regression or issue reports or other follow up
comments, as they may result in the patch/series getting dropped or
reverted. Patches applied to an "unstable" branch are accepted pending
wider testing in -next and any post-commit review; they will generally
be moved to the main branch in a week if no issues are found.

Best regards,
-- 
Cheers,
Nathan