Re: [PATCH] make-mod-scripts: Fix a rare build race condition

["Bruce Ashfield" <bruce.ashfield@gmail.com>]

On Wed, May 27, 2020 at 1:46 PM Khem Raj <raj.khem@gmail.com> wrote:
>
> On Wed, May 27, 2020 at 9:57 AM Bruce Ashfield <bruce.ashfield@gmail.com> wrote:
> >
> > On Wed, May 27, 2020 at 12:03 PM Khem Raj <raj.khem@gmail.com> wrote:
> > >
> > > There is a build break which often happens whem using 4.1 kernel
> > >
> > > /bin/sh: 1: scripts/basic/fixdep: Permission denied
> > > scripts/Makefile.host:124: recipe for target 'scripts/dtc/srcpos.o' failed
> > > make[3]: *** [scripts/dtc/srcpos.o] Error 126
> > >
> > > this patch sequences the build targets so it can work reliably with
> > > different kernel versions
> > >
> > > Signed-off-by: Khem Raj <raj.khem@gmail.com>
> > > Cc: Bruce Ashfield <bruce.ashfield@gmail.com>
> > > ---
> > >  .../make-mod-scripts/make-mod-scripts_1.0.bb               | 7 ++++---
> > >  1 file changed, 4 insertions(+), 3 deletions(-)
> > >
> > > diff --git a/meta/recipes-kernel/make-mod-scripts/make-mod-scripts_1.0.bb b/meta/recipes-kernel/make-mod-scripts/make-mod-scripts_1.0.bb
> > > index 0be1422a24..c7edb20ee4 100644
> > > --- a/meta/recipes-kernel/make-mod-scripts/make-mod-scripts_1.0.bb
> > > +++ b/meta/recipes-kernel/make-mod-scripts/make-mod-scripts_1.0.bb
> > > @@ -23,7 +23,8 @@ EXTRA_OEMAKE = " HOSTCC="${BUILD_CC} ${BUILD_CFLAGS} ${BUILD_LDFLAGS}" HOSTCPP="
> > >  #
> > >  do_configure() {
> > >         unset CFLAGS CPPFLAGS CXXFLAGS LDFLAGS
> > > -       oe_runmake CC="${KERNEL_CC}" LD="${KERNEL_LD}" AR="${KERNEL_AR}" \
> > > -                  -C ${STAGING_KERNEL_DIR} O=${STAGING_KERNEL_BUILDDIR} scripts prepare
> > > -
> > > +       for t in prepare scripts_basic scripts; do
> >
> > Last I checked, we don't actually need scripts_basic.
> >
> > Isn't just sequencing prepare, followed by 'scripts' enough ?
> >
> > If not, we really should put in the long log why we need that new
> > target when sequencing, when we didn't need it before.
> >
>
> in a way you are right that scripts should cover it, but calling it
> out explicitly avoids any weird races if any and it does not
> hurt until this target is removed. I really have not debugged kernel
> build to see what is causing this, so there is not much
> details to add other than this that we are handing some race
> conditions which ideally should be in the makery
>

But the race condition is handled with the two targets, no ? I realize
it doesn't hurt, but you are implying that you need all three to be
sure, but that really isn't the case from what I've seen.

I just think simpler is better, but don't take my comments as an objection.

Cheers,

Bruce

> > Bruce
> >
> > > +               oe_runmake CC="${KERNEL_CC}" LD="${KERNEL_LD}" AR="${KERNEL_AR}" \
> > > +               -C ${STAGING_KERNEL_DIR} O=${STAGING_KERNEL_BUILDDIR} $t
> > > +       done
> > >  }
> > > --
> > > 2.26.2
> > >
> >
> >
> > --
> > - Thou shalt not follow the NULL pointer, for chaos and madness await
> > thee at its end
> > - "Use the force Harry" - Gandalf, Star Trek II



-- 
- Thou shalt not follow the NULL pointer, for chaos and madness await
thee at its end
- "Use the force Harry" - Gandalf, Star Trek II