Re: [PATCH] kbuild: Add an option to skip vmlinux.bz2 in the rpm's

[Zack Rusin <zackr@vmware.com>]

On Tue, 2022-09-27 at 02:38 +0900, Masahiro Yamada wrote:
> ⚠ External Email
> 
> On Fri, Sep 23, 2022 at 3:45 AM Zack Rusin <zack@kde.org> wrote:
> > 
> > From: Zack Rusin <zackr@vmware.com>
> > 
> > The debug vmlinux takes up the vast majority of space in the built
> > rpm's. While having it enabled by default is a good idea because it
> > makes debugging easier, having an option to skip it is highly valuable
> > for CI/CD systems where small packages are a lot easier to deal with
> > e.g. kernel rpm built using binrpm-pkg on Fedora 36 default 5.19.8 kernel
> > config and localmodconfig goes from 255MB to 65MB which is an almost
> > 4x difference.
> > 
> > To skip adding vmlinux.bz2 to the built rpm add SKIP_RPM_VMLINUX
> > environment variable which when set to "y", e.g. via
> > "SKIP_RPM_VMLINUX=y make binrpm-pkg" won't include vmlinux.bz2 in the
> > built rpm.
> > 
> > Signed-off-by: Zack Rusin <zackr@vmware.com>
> > Cc: Masahiro Yamada <masahiroy@kernel.org>
> > Cc: Michal Marek <michal.lkml@markovi.net>
> > Cc: Nick Desaulniers <ndesaulniers@google.com>
> > Cc: linux-kbuild@vger.kernel.org
> > Cc: linux-kernel@vger.kernel.org
> > ---
> >  scripts/package/mkspec | 10 ++++++++--
> >  1 file changed, 8 insertions(+), 2 deletions(-)
> > 
> > diff --git a/scripts/package/mkspec b/scripts/package/mkspec
> > index 7c477ca7dc98..5a71fc0852b0 100755
> > --- a/scripts/package/mkspec
> > +++ b/scripts/package/mkspec
> > @@ -23,6 +23,12 @@ else
> >         M=DEL
> >  fi
> > 
> > +if [ "$RPM_SKIP_VMLINUX" = y ]; then
> > +       D=DEL
> > +else
> > +       D=
> > +fi
> > +
> >  if grep -q CONFIG_DRM=y .config; then
> >         PROVIDES=kernel-drm
> >  fi
> > @@ -94,8 +100,8 @@ $M   $MAKE %{?_smp_mflags} INSTALL_MOD_PATH=%{buildroot} modules_install
> >         $MAKE %{?_smp_mflags} INSTALL_HDR_PATH=%{buildroot}/usr headers_install
> >         cp System.map %{buildroot}/boot/System.map-$KERNELRELEASE
> >         cp .config %{buildroot}/boot/config-$KERNELRELEASE
> > -       bzip2 -9 --keep vmlinux
> > -       mv vmlinux.bz2 %{buildroot}/boot/vmlinux-$KERNELRELEASE.bz2
> > +$D     bzip2 -9 --keep vmlinux
> > +$D     mv vmlinux.bz2 %{buildroot}/boot/vmlinux-$KERNELRELEASE.bz2
> >  $S$M   rm -f %{buildroot}/lib/modules/$KERNELRELEASE/build
> >  $S$M   rm -f %{buildroot}/lib/modules/$KERNELRELEASE/source
> >  $S$M   mkdir -p %{buildroot}/usr/src/kernels/$KERNELRELEASE
> > --
> > 2.34.1
> > 
> 
> 
> 
> 
> This came from fc370ecfdb37b853bd8e2118c7ad9f99fa9ac5cd
> I do not know how useful or annoying it is.
> Presumably, it was a cheesy work, and rather annoying than useful.
> 
> 
> In debian (scripts/package/mkdebian), this kind of stuff is
> a separate debug package, and only built when CONFIG_DEBUG_INFO=y.
> 
> 
> Take more time in case somebody may come up with a better idea.

I'd be happy to rework it in whatever way would be more convenient. Because rpm
builds already depend on environment vars due to RPMOPTS I thought this approach was
fitting but I'm not particularly attached to it. The important thing is the the end
result of not including vmlinux.bz2 in the rpm itself.

I think the other reasonable question to ask is: is anyone still using vmlinux.bz2
from rpms? Because maybe just removing that code completely is the better option
here.

z